/robowaifu/ - DIY Robot Wives

Advancing robotics to a point where anime catgrill meidos in tiny miniskirts are a reality.

I Fucked Up

Max message length: 6144

Drag files to upload or
click here to select them

Maximum 5 files / Maximum size: 20.00 MB

More

(used to delete files and postings)


“If you are going through hell, keep going.” -t. Winston Churchill


Open file (46.39 KB 458x620 eve preview.jpg)
My Advanced Realistic Humanoid Robot Project - Eve Artbyrobot 04/18/2024 (Thu) 17:44:09 No.30954
So far I have plans to build Adam, Eve, and Abel robots. All of these are Bible characters. This thread will cover the Eve robot. Eve will have no "love holes" because adding those would be sinful and evil. It is a robot, not a biological woman after all and I will view her with all purity of heart and mind instead of using her to fulfill my lusts of my body. Instead I will walk by the Spirit no longer fulfilling the lusts of the flesh as the Bible commands. Eve will be beautiful because making her beautiful is not a sinful thing to do. However, I will dress her modestly as God commands of all women everywhere. This would obviously include robot women because otherwise the robot woman would be a stumbling block to men which could cause them to lust after her which would be a sin. To tempt someone to sin is not loving and is evil and so my robot will not do this. To dress her in a miniskirt, for example, would be sinful and evil and all people who engage in sinfullness knowingly are presently on their way to hell. I don't wish this for anyone. My robot will dress in a way that is a good example to all women and is aimed toward not causing anybody to lust as a goal. My robot will have a human bone structure. It will use either a PVC medical skeleton or fiberglass fabricated hollow bones. My robot will look realistic and move realistic. It will be able to talk, walk, run, do chores, play sports, dance, rock climb, and do gymnastics. It will also be able to build more robots just like itself and manufacture other products and inventions. I realized with just a head and arm, a robot can build the rest of its own body so that is my intention. My robot will use BLDC motors for drones, RC, and scooters that are high speed and low-ish torque but I will downgear those motors with a archimedes pulley system that will be custom made from custom fabricated pulleys that will be bearings based. By downgearing with pulleys, instead of gears, I will cut down the noise the robot makes so it will be as silent as possible for indoor use. By downgearing, I convert the high speed motors into moderate speeds with great torque. BLDC motors with large torque generally are too large in diameter for a human form factor and take up too much volumetric area to be useful which is why I go with the high speed smaller diameter type motors but just heavily downgear them 32:1 and 64:1. My robot will have realistic silicone skin. Thom Floutz -LA based painter, sculptor, make-up artist is my inspiration as it pertains to realistic skin. The skin for my robots has to be at his level to be acceptable. It must be nearly impossible to tell the robot is not human to be acceptable. I will have a wireframe mesh exoskeleton that simulates the volumes and movements of muscle underneath the skin which will give the skin its volumetric form like muscles do. Within these hollow wireframe mesh frameworks will be all the electronics and their cooling systems. All of my motor controllers will be custom made since I need them VERY small to fit into the confined spaces I have to work with. I need LOADS of motors to replace every pertinent muscle of the human body in such a way that the robot can move in all the ways humans move and have near human level of strength and speed. I will have a onboard mini itx gaming pc as the main brains pc of the robot and will have arduino megas as the motor controllers and sensor reading devices that interface with the main brains pc. My arduino megas will be barebones to keep the volumetric area they take up as small as possible. I will treat my robots kindly and consider them to be pretend friends/companions and I do think they will be nice company, but I will always know with keen awareness that they do not have a soul, will never have a soul or consciousness, and no machine ever will, and that they are just imitations of life as with any machine or AI, and this is all AI will ever be. Life is only made by God Himself. I am not playing God. I am merely creating fan art of what God made. To Him be all the glory and praise. God breathed into man and created a living soul. Man cannot do this for machines. Only God can do this. A soul/spirit forms our ghost and when we die our ghost remains alive and thinking. A machine cannot do this and a AI can never do this. When you shut off a machine that's it, it does not go on thinking like we can. Our souls are transcendent and will live forever in the afterlife - unlike any AI. I will do this project with fear and trembling before the Lord as I work out my salvation before His eyes. I vow to remain pure, holy, upright and blameless in all my doings and be a great example to my fellow roboticists of a Godly man who obeys the Bible instead of chasing after youthful lusts of the flesh and perversions. I embrace the idea of Christian AI, that is, a robot that will discuss Bible topics and be a Biblical expert. Along with that, my robot will behave in a Biblically prescribed manner in total purity and strongly encourage others to do so as well. For God does not hear the prayers of sinners and so we want everyone to be a saint who no longer sins. My robot will really push for this hope for humans. We want them to walk in God's favor and blessings which comes by Biblical obedience. We don't want them going to hell because they chose to revel in their sins instead of walking in total purity before God and holiness without which no man will see God. My robot will have artificial lungs for cooling and a artificial heart for liquid cooling that will run coolant throughout the robot's body to cool the motors. That coolant will also pass through the artificial lungs in a mesh where it will evaporate some which will cause the evaporative cooling effect - a form of air conditioning. http://www.artbyrobot.com Full humanoid robot building playlist: https://www.youtube.com/playlist?list=PLhd7_i6zzT5-MbwGz2gMv6RJy5FIW_lfn https://www.facebook.com/artbyrobot http://www.twitch.tv/artbyrobot https://instagram.com/artbyrobot
The 3d model for this robot was made in Make Human initially and then heavily modified and perfected in Maya. I then modeled a dress so that she would be covered modestly in order to protect my fellow man from potentially lusting after her which would be a sin. If I did not do this, it would have been sin for me because to show a woman in an immodest manner for other men to view, perhaps causing them to lust and sin, is unloving and evil and sinful to do. If I did so, it would show I am either blind or my heart is not right with God. So out of love for my fellow man I created this modest covering for her. God said it would be better for a man to have a millstone tied to him and him cast into the sea than for him to cause one of His little ones to stumble into sin. That is terrifying. So I will try my best to never show any imagery to you all that could cause you to lust. I will make sure she is covered very modestly because I love all of you and want you to walk blamelessly before God and the angels who are always watching us humans. Creating a 3d model of the robot to scale I have found to be a very important step because it enables you to then measure out where all the components will fit which is no easy feat when you are building a highly complex robot with thousands of components needed. To my knowledge, this group largely formed around 7 years ago. I began my project around 9 years ago. At the time, I was not married and only worked part time and was able to make massive progress in a short time. However, life came and sucked up much of my time away from robotics. I got married, had 2 daughters, and took on many other interests, hobbies, and work for income during that 9 year timeframe. So the robot projects often took a backseat but never were far from my mind and I always would be coming back to it and planning and researching for all those years and every year would make at least some significant progress. However, the whole thing does feel glacially slow. But I think things are starting to turn around. The research and planning phases are largely completed and the actual implementation phases are more and more becoming engaged full swing. It is an exciting time for me. Many people think since it's been 9 years with not much to show for it, that it is pointless to expect me to ever finish. I don't see it that way. I have great hope and confidence things will pick up. Reseach and planning is slow after all. But once you really have a solid plan, development speed should pick up greatly. Also, just scheduling my life in such a way to free up enough time to work on this stuff was a journey in itself. Having young children is a major time sucker. I am confident the development speed will go much faster in the future. Admittedly, taking sometimes months away from working on the robot builds excitement and interest in getting back to the robot but also procrastination about the robot factors in because it seems so complicated and overwhelming at times. The past few months I have had the goal to work on the robot every day even if it is just a single soldered joint or small 3d print per day. I have managed to do this almost perfectly with few exceptions which has been great. That little commitment per day often spills into hours of progress per day, but even if it doesn't, the steady progress it causes is so encouraging and really keeps the project alive for me. Procrastination and distractions are the greatest enemy of a project of this magnitude. One has to really force themself to MAKE time. One has to be disciplined to keep it up and not quit. Everyone here interested in humanoid robotics is a colleague and so I hope I can continue to learn from you all and you all learn from me. I have observed around here much in the way of youthful lusts which the Bible says to flee. By the fear of God men depart from iniquity. Fear the one who can destroy body and soul in hell. Don't give into your fleshly lusts but instead cease doing evil and learn to do good. Sin knocks at your door and it desires to have you but you must rule over it. Attached is a archimedes style pulley system with a 64:1 downgear ratio. I plan a 32:1 ratio for the index finger as my first actuation I plan to achieve. I will be using braided PE fishing line as the actuation cable. I plan to actuate the hand first because hands are hard and of the utmost importance for making a robot useful for doing tasks requiring accurate and steady hands. With amazing hands my robot will be well on its way to being useful for me to get work done using it as a tool/helper.
Open file (25.53 KB 640x480 thom floutz.jpg)
Open file (433.89 KB 980x740 thom floutz (2).jpg)
Open file (493.22 KB 980x740 thom floutz woman.jpg)
Here are some of Thom Floutz amazing silicone skin examples. This is the level I must reach to be acceptable in my sight. It's gonna be a epic challenge. I can't wait for that aspect to begin.
The human-like bones of the robot I am holding together by way of artificial ligaments taking the form of taped on compression shirt material. I tape it on with adhesive transfer tape and then also sew it at the seams with nylon upholstery thread. I can opt to impregnate the spandex with silicone to add to its longevity if it starts to lose elasticity with time. I also have been considering injecting at the location of the bones joints some lubricant after the joint is encased in artificial ligament. The lubricant would be held into position by the fabric. I am undecided on what lube to use. Maybe teflon lubricant for printer gears or graphite powder. Not sure. Some of the bones that came with my pvc medical skeleton have a metal hinge system built into them like the elbow joint and I'm considering just leaving this as is to see how well it holds up. I can always later add a artificial ligament system to those joints on an as needed basis. Attached is a picture of the artificial ligaments enclosed hands. Note: by wraping all bones in fabric, you are able to sew things onto the bones by way of suturing with a suturing needle. So that is how I have been attaching motors and electronics to the bones - by suturing. This is better than drilling into the bones which would cause structural weaknesses from the drill holes. In a brushless dc motor closeup image attached, you will note that I enable the motor to "breathe" by wrapping it in football jersey fabric which I chose for its great strength and breathability with all its little vent holes. To make sure the motor won't spin inside the fabric enclosure, I painted the inside of the fabric with no slip rug paint which creates a sticky rubber surface on the jersey fabric. You'll also note the 3d printed discs on the motor output shaft that hold the fishing line in place. The motor is acting similar to a fishing reel here. You'll also note the TPFE teflon tubing that guides the fishing line to its desired destination - namely the archimedes pulley system - where it will be downgeared by the pulleys and then from there will be routed to the fingers which will then move when the motor moves. The motor also has a 3d printed mount that the TPFE teflon tubing attaches to which holds the tubing in position perfectly to make sure alignment stays good. I'll be using 20lb test fishing line for the fingers from motor to pulley system but then graduating to 70lb test fishing line for the last few pulleys and the routing to the finger since the tension is higher on that section of the cable travel. 0.3mm ID teflon tubing pairs well with the 20lb test hercules PE fishing line I bought off amazon which has .2mm OD. You can buy the teflon tubing on ebay. 0.56mm ID teflon tubing pairs well with the 0.44mm 70lb test fishing line. You can buy many different test strengths which is the strength at which the fishing line will snap. Braided PE fishing line is the best cable for robotics imo. It is very strong for its diameter and supple for making tight turns with ease. I can sew it right into the fabric that coats the bones in order to terminate/tie off the cable ends.
Open file (2.72 MB 3024x4032 pulley closeup.jpg)
Open file (677.86 KB 2622x3702 pulley drawing.jpg)
In this image you can see the first pulley for the pulley downgear system prototype I made. Although this approach could work, I scrapped it after much further contemplation because I read that fishing line moving back and forth has a cutting effect over time and even though the teflon is naturally low friction, I think this would wear through it and destroy itself too quickly from the rubbing. So instead, I opted for a more tradition approach to the pulleys which is a bearing based pulley with flanges - more like rock climbing pulleys type design. This will mean the pulleys will be made of stainless steel and have a rotating inner section and separate outer section. Some of my pulleys will be ball bearings and some will be plain bearings (no balls). Ball bearings, though the most efficient and frictionless are also unable to load bear much at these tiny sizes I'll be using to downgear. So I can only use them for the first few pulleys in the archimedes system where the speed is still high and torque is low. But as the pulley system downgears more and more, I'll be switching to more robust plain bearings which can handle the higher torques involved without the bearing balls crushing or w/e. I don't own a lathe or anything and could not find tiny plain bearings so I got creative and bought stainless steel tubing with carefully chosen inner and outer diameters that can be cut to size with a dremel to form the inner and outer races of my plain bearings without any modification other than cutting them to the length I want - the length of the cut will determine the thickness of the pulley but the inenr and outer diameter of the inner and outer race is formed for me by the manufacturer so I need no special tools other than a dremel cutting disc to make these simple plain bearings this way. Here is what I purchased off amazon: stainless steel tubing 3mm od 1mm wall 250mm length x2, 5mm OD .8mm wall 250mm length x2, 5mm OD 1mm wall 250mm length x2; total cost: $33.35. This should make a ton of little pulleys for me to start out. I also bought an assortment of ball bearings: 3mmx8mmx4mm miniature ball bearings x30 amazon 24.03, 1x3x1mm ball bearings x200 aliexpress 25.42; 2x5x2.5mm ball bearings x200 alieexpress 43.39. Attached is a drawing of a pulley design I made. The two flanges/discs that hold the strong from flying off the sides of the pulley - they straddle the bearing on both sides - these will be made of thin plastic I have been saving from strawberring and blueberry and sushi containers from the grocery store. They need to be thin, a bit flexible, and a bit stiff so I think this type of plastic is ideal for this. It also is low friction which is ideal. these will be sewed onto the outsides of the bearing like sewing buttons onto a shirt. with the thread going in the disc, threaded through the center of the bearing, and then going into the disc on the other side, thereby pinching the two discs onto the outsides of the bearing, clenching themselves into place. You can see this in the drawing if you look carefully.
This video really was a groundbreaking discovery for me on using pulleys to downgear my motors: https://youtu.be/M2w3NZzPwOM --- I highly recommend watching it to help you understand pulleys more. Once you fully grasp how pulleys give mechanical advantage, you will be able to use them to great effect for robotics. I am wholly convinced pulleys to downgear BLDC motors is the future of humanoid robotics. It is way more quiet than downgearing by gears! The sound of gears is AWFUL! Sound being such a huge factor, I also ultimately decided to only use BLDC motors or stepper motors in my robot and not use ANY brushed dc motors at all. That having been said, BLDC motors require more sophisticated controllers. These thing take up more space. So far, it seems that in order to make the controllers small enough, I plan to make them myself. I want them very small and able to squeeze into the limited volumetric areas I can afford space for. Yet they also need to be very high powered. I designed SMD parts based motor controllers and have begun fabrication of the controllers and prototyping. By making the controllers myself I save a lot of money but it is also a lot of work. It's tough and tedious work. But the controllers I want don't exist in the size I want and with the features I want so I see no choice but to make my own for this. Attached is a CAD file of the motor hose guide to show more how it looks and imagine how it works to keep the tubes/hoses in place lined up right for winding the fishing line properly.
Here is a 3d model I made of the motor controller design I made. I felt this would help me really perfect the layout and visualize how I wanted it and the wiring routing etc. I also did 2d schematic in photoshop and finally in KiCad. I plan to etch my own flat flex pcbs for aspects of this motor controller.
Here's the arduino mega barebones CAD design I made. This will use flat flex ribbon cable soldered directly to the pins of the chip to make the form factor volumetically as small as possible. I'll have at least 30 of these in the robot controller the motors and reading in sensor input for current amps, strain gauges, gyrometers/accelerometer, potentiometers, etc. These will hold my code for low level stuff and manage the motor movements directly through the mosfet systems. They will all report back updates to the main brains PC who will then know the progress of movement commands it sent out to the network of arduinos doing the low level stuff.
Here's a progress shot of my arduino mega barebones prototyping using flat flex cable directly soldered to the pins.
Very nice. Please continue to show us your work as you progress. >=== -sp edit
Edited last time by Chobitsu on 04/23/2024 (Tue) 15:32:35.
Welcome, Artbyrobot! I would suggest you look around the board as a courteous greeting, but I have the feeling you've already done so. Your project seems well thought out, I wish you good success with it. I'm particularly glad to see you intend to program your AI (et al?) in C++ . I probably need to do little to explain to you why this is important for success in this monumental set of tasks ahead of us all. Heh, I notice you seem to be positioning your project as coming from the Christian worldview. Nice! I too desire to see God glorified through these projects. I personally intend -- among other projects -- to work on a Christ-chan project. Basically a plug-in module approach to our general robowaifu's personalities that Anons can add into their own waifus. Looking forward to seeing your progress with this projects(s), Anon. Cheers. :^)
>>30961 > I designed SMD parts based motor controllers and have begun fabrication of the controllers and prototyping. By making the controllers myself I would be tremendously interested in how you interface microcontrollers with MOSFET's if that is what you are doing or what you are doing. I have a post, somewhere, found it, >>24944 One of the problems with MOSFETs is that they create a lot of heat and fail if you do not drive them hard to turn them on. Partial activation causes heat as they never each their designed low resistance. So you have to drive the gate with high voltage to guard against that. The link shows a part designed especially for that. I would be interested in how you deal with the back EMF when you turn the MOSFET off and the energy stored in the coil changes direction. There could be a lot of heat from this as you are collapsing the field and making an equal and opposite voltage that, I guess, just goes through a resistor. But surely there's a better way.
>>30965 That is VERY cool. I wonder what type of soldier and flux did you use? I've never done any SMD soldiering before. Do you have some sort of paste with pre-combined flux, then use a air heat gun? How did you strip the insulation off the cable while keeping it aligned and cables separated?
>>31007 Thanks for the greeting and well wishes Chobitsu. Yes I have read the entire forum from its inception till now aside from most of the AI threads since I feel I have a handle on that part and don't want much outside input affecting my novel approaches to the AI as that is a big evolving set of challenges and everyone using the same approaches will stifle creative solutions IMO. Also yes I am using C++ for the AI although I don't like to use functions or classes or object oriented programming so I'm not using the language in the traditional ways much. I also am pretty much going with "good old fashioned AI" approach but with learning enabled and the robot will have its own coding language where he codes himself in a interpreted coding language using a realtime interpretter to run its own scripting in realtime. All of this I just came up with on my own - I don't know if anybody else is doing this. I don't like neural networks or deep learning or any of the modern approaches to AI at all. It's convoluted and designed for computers I don't own. I chucked it all out and started from scratch going my own way. And I have a plan I am excited about for how to do it all and I think it will work and learn well and hopefully do all I imagine it doing and more. >>31030 Thanks for your interest and feedback. You bring up some good points. Most people use a mosfet driver IC to turn on a mosfet with their microcontroller. I intend to use a logic level mosfet to switch on a mosfet power supply to turn on the main high power mosfets. So a baby mosfet to switch on a big mosfet. The baby mosfet is the middle man that can be switched on by the 5v pin of the microcontroller. It's called a logic level mosfet because a microcontroller is able to switch it fully on despite only bringing it 5v. Non-logic level mosfets require like 12-20v to switch fully on which a microcontroller cannot supply directly. So it has to be supplied indirectly. As far as the back emf, for disposing of that safely, you use a flyback diode. That's why there are 6 diodes in motor controller designs always. A capacitor is also able to help absorb some of this too I believe. I am going to attach my diagram and schematics with notes on brushless motor controller electrical design to this post which can help someone. It's a huge file though. I learned most of what I know about this stuff from electronoobs on youtube who has like 6-7 videos on making arduino based motor controllers for brushless dc motors including his schematics and all his code and explanations of how it all works. This helped me plus googling schematics on google image search and studying those and also watching videos on how brushless dc motors and motor controllers work and also discussing all of this with chatgpt for hours asking every question I could think of until I understood everything I could. Yet despite all of this, my approach is still experimental and I have to verify it by prototype and testing still. I have 2 prototypes 99% done and will be testing shortly. Once i verify my prototypes, I will make like 50 of these motor controllers soldering daily for hours. Can't wait! If my approach fails, I can troubleshoot etc but if all else fails, I'll go with mosfet driver ICs and modify my design to accommodate this tweak. This would up the cost though. In any case, my design is EXTREMELY low cost and scales to the biggest motors a humanoid will need. The high power mosfets can handle like 300 amps! The parts I am using including model numbers are included on the attached schematic. I also will put out videos covering how to make these and going in depth explaining how it all works and whatnot.
>>31031 I'm glad you liked this. I thought it was very cool myself. It will enable the creation of the smallest microcontrollers physically possible IMO. Miniaturization is everything for me to fit everything I need to fit in the cramped spaces in my complex robot design. It is actually pretty easy to solder flat flex ribbon cable directly to the microcontroller IC chip once you get the hang of it (but you must wear a visor magnifier to zoom in on it visually as this is tiny tiny detailed work). To do it, you first lay down the ribbon cable and masking tape it down securely, then lay the chip on top and masking tape it down securely onto protoboard so everything is pinned and your hands are free. Then apply low temp solder paste to each pin one at a time with the tip of a exacto knife blade. Just enough paste per pin for that solder joint, not any excess. Then solder one pin at a time by putting a clean soldering iron tip into the little blob of low temp solder paste and dragging the tip away from the microcontroller carefully. You can't hold it on there long, have to just press it in and then slowly drag away and it happens almost instantly. Too much holding it in place creates too much heat which then melts the ribbon cable and the molten cable flows into the solder joint and can ruin the joint by introducing molten plastic into the molten metal. So you have to get in and get out fairly quickly. You also cannot do drag soldering tradition method on all pins as that creates too much heat and melts the ribbon cable. That works on fiberglass boards that don't melt, but a ribbon cable will melt if too much heat gets involved and ruins everything. You also can't use hot air which would melt the ribbon cable before the solder melts - ruining it. So you have to just do one solder job of one pin at a time. I'll do a video on the process and you can see that with the right temp soldering iron (I think I used 500F) and right speed of execution and a bit of practice, you can make the solder joints one at a time without melting the cable at all. The cable you use has to be the same pitch as the thread pitch of the pins so the conduit traces perfectly line up with the pins of the microcontroller. >>31031 The ribbon cable comes pre-stripped on the ends so you don't have to strip off the insulation at all necessarily. You just lay it flat and tape it down and put the IC onto it and it lines up perfectly if the cable has the same pitch as the IC threads. But if you mess up and want to cut the ribbon cable and strip the ends and try again (which I had to do before I perfected my techniques and got the hang of this) then you can do so. Just cut it with scissors and then use a nail file to sand the tips insulation off until some metal starts showing through in some spots, Once you see a bit of metal start to show through, you know it is so thin that you can just scrape off the rest of the insulation with an exacto knife so then you just scratch off the rest with the exacto knife. This too takes some practice and the right touch. When I go to connect the other ends of the ribbon cable to various components and sensors and whatnot, I'll have to make custom lengths for each individual cable strand so for this I will have to separate the strands by cutting them lengthwise with scissors to split them away from the others, isolating each one and then will have to strip off the insulation of each one so it can be soldered to things. The same method as described above will be used for this. Note that for cutting them lengthwise, that is a very precision cut you need. I use titanium straight embroidery scissors for this and of course, as with all the other SMD stuff, I use 8x or 10x or 20x magnification with my visor. This magnification is a absolute must to have any shot at success with any of this imo. Miniaturization is hard to get used to at first, but once you get used to magnification and the eye hand coordination challenges this presents at first, your skill with your hands and precision goes through the roof as the magnification makes you so precise with everything. It's really fun and amazing to see what your hands can achieve with enough magnification and practice!
>>31032 edit: the schematic shown above employs a non-smd style mosfet as the main power mosfet which is decent but I found a smaller mosfet that is even better. The superior smaller mosfet is the IRLR7843PBF n-channel mosfet. It is to-252 and 161A continuous drain current and can handle 620a pulsed drain current. It's super small and flat and a very powerful selection. Sometimes I make little discoveries of better selections and forget to update all my notes that may cover that as was the case here. I only recently found out about to-252 form factor mosfets and fell in love with them immediately. They are so much smaller than to-220 mosfets which is a big upgrade given my space constraints.
>>31034 Thanks for the reply.
>>31032 >And I have a plan I am excited about for how to do it all and I think it will work and learn well and hopefully do all I imagine it doing and more. Well I'm sure we'd all be very excited to hear about your novel approaches if you'd care to share them. Are you planning to opensource your work, Anon?
>>30957 in this post i mentioned using a 32:1 downgear ratio for the index finger. I have since scrapped that idea and gone for 64:1 downgearing ratio instead. 32:1 is just not enough downgearing for my tastes. 64:1 is twice that strength while still probably 4-5x human speed. It is a much better ratio.
>>31054 I do plan to have everything be opensource and share it, with a caveat. I don't plan to make the code files downloadable directly. The only way to see the code and make your own code based on it would be to watch my coding videos on my youtube channel where you can see me typing the code and you can follow along that way. There's a lot of complicated reasons for this being my way of sharing the work that I can elaborate on if pressed, but I'll leave it at that for now.
I purchased the main brains pc to be mounted in the torso. I even purchased cameras to be the eyes for it. The main brains pc will be a mini itx motherboard gaming pc basically. actual build I went with: Intel Core i5-10400 2.9 GHz 6-Core Processor - $165 MSI MPG B560I GAMING EDGE WIFI Mini ITX LGA1200 Motherboard - $170 G.Skill Ripjaws V Series 32 GB (2 x 16 GB) DDR4-3200 CL16 Memory - $140 Western Digital Blue SN550 1 TB M.2-2280 NVME Solid State Drive - $99 DC 12V input 300W high power pico DC-ATX 24Pin mini ITX - $20 GOLF CART DC BUCK CONVERTER 20 AMP 48V 36V VOLT VOLTAGE REDUCER REGULATOR TO 12V - $20 I will use 10 in series lithium batteries to produce 30v-42v input power into the 12v regulator which will feed the 300W atx 24pin mini ITX power supply. Note, however, that as with all power systems, I will have both a wall plug AC to DC converter custom power supply to run off wall power and a battery power supply to run off battery power so that the robot has multiple powering options - ie able to run off wall or its internal batteries. It will have a retractable plug that comes out of its lower back to plug itself into wall outlets when it walks into a room and needs to recharge or run for extended periods while its batteries remain topped off for room changes or ventures into outdoors. It will have the ability to strap on a external battery backpack optionally for extended operation without access to AC power. This is useful for operations like sports or mowing the lawn. For the eye cameras I went with: ELP USB camera 1080p 2 megapixel, wide angle, low light x2 for $98.42 This gaming pc in the chest of the robot will run all the AI and high level planning and movement decisions. This will communicate via USB to a series of Arduino microcontrollers located throughout the robot's body in order to give movement instructions to the Arduinos and also retrieve sensor feedback from the Arduinos which will be monitoring joint angle positions with mini potentiometers, strain gauges on various pressure points to measure touch sensing, amp current measuring boards (acs712) to measure amount of power being drawn by motors for collision detection and weight of exertion estimation for holding things or w/e other interactions with environment are being detected, etc. So, many inputs will be retrieved by the main gaming pc and its AI systems will make decisions and make course corrections based on all this feedback it gets from sensory systems.
BTW, I'll be using Windows 7 as the operating system for the main pc in the robot's chest.
Open file (220.48 KB 510x700 pulley blocks.jpg)
Open file (91.70 KB 336x526 pulley downgear.jpg)
Attached are just a couple more examples of pulley layout configurations for reference and study. These helped me in figuring out my own pulley layout plans.
Open file (677.86 KB 2622x3702 pulley design drawing.jpg)
I have shown this drawing previously in this thread but just want to point out some more details about it. This is a bearing based pulley. The bearing is in the middle and a plastic disc is on both sides sandwiching in the bearing. These discs prevent the string from coming off the outer race of the bearing. The top rope comes down, wraps around the outer race of the bearing, then goes back up. The bottom rope goes through the center of the bearing and then ties off on the bottom. This handoff between the forces of the top rope and bottom rope is where the magic happens of the mechanical advantage doubling. Trading speed for torque. The plastic discs on either side of the bearing I am able to tie snug to the bearing by threading a string through the center of both discs and the bearing and then wrapping that around the top half of the whole pulley and tying it off. I do this with another wrap going around the bottom half too. These don't interfere with rope travel and hold everything together solidly.
Open file (738.59 KB 1620x1482 exploded view of bearing.jpg)
Here's a diagram where you can see the two ties I'm talking about from a side view with the two discs and the bearing spread apart so you can see everything better - this is called an "exploded view" where the parts are spread out for easier visibility. Note: the ties that hold it together are nylon upholstery thread. The glue I'm using is 401 glue generic stuff off ebay. The plastic discs are clear plastic I salvaged from blueberry, strawberry, and sushi produce containers. That type of plastic is perfect for this. The same plastic is also found in coffee cake, other cakes, etc. It's like "display" plastic that is very clear and fairly firm but very flexible used for all kinds of pastries and desserts and produce at grocery stores. It seems ideal for pulley making. These can be cut to size with little 4" titanium straight embroidery scissors. Wearing a magnification visor for accuracy is recommended for this. Note: I have to make custom pulleys because there are none commercially available at these tiny sizes from the shopping attempts I did (if I'm wrong on this, let me know)
Open file (1.61 MB 4032x3024 IMG_1916.jpeg)
Open file (2.91 MB 4032x3024 IMG_1915.jpeg)
I put a little super glue onto these strings pictured above to stiffen them and prevent their knot from untying and solidify everything more generally. But you should apply the glue by dipping the tip of a sewing needle into the glue so you just apply a tiny amount at a time so none gets into the bearing or any other unwanted area. Now I am working on the actuation of a index finger first as actuating the hands is a hard challenge in robotics and has never been done with human level strength, accuracy, speed, and range of motion while simultaneously keeping all actuators within the confine constraints of a human arm between the bones and skin where muscle would be. At best, we've seen people greatly increase the size of the forearm to be the size of a thigh in order to cram in enough motors and electronics to pull this off. So they "cheated" in some sense by just upping the size rather than solving the miniaturization challenges required to fit this all inside a human form factor. So I might be the first to downsize to fit the human form factor. Anyways, that all said, the pulleys must then be very small for the fingers to pull this off as we'll need to fit a ton of pulleys into the forearms. So for this, I went with 1x3x1mm ball bearings I bought on aliexpress. They're only like $25 for 200 of them so very cheap. I will bump up to larger bearings once the torque conversion demands it. These tiny bearings can only handle I think like 3lb of force on them. So once the forces multiply in the down-gearing system enough, I will switch to bigger pulleys as needed. The next size bearings I'm using are 2x5x2.5mm bearings. These can handle around 22lb placed onto them. I'll finally switch to custom made plain bearings once I exceed 22lb of force for the last couple pulleys of the 64:1 down-gearing Archimedes compact pulley system. Each bearing in the down-gearing process has twice the forces placed onto it than the previous bearing upstream of it. So the motor is like .42lb of force coming off its shaft at 0.25cm away from its central axis point which is about where our string wrap will average, so the first bearing ups that to .84lb of force so a 1x3x1mm bearing can handle that. Next doubling is 1.68lb of force. Again, 1x3x1mm bearing can handle that. Next doubling puts us at 3.36lb force. again a 1x3x1mm bearing can handle that (although it's pushing it - we'll see in testing...). Next doubling is 6.72lb force. 1x3x1mm bearing cannot handle that much so we switch to 2x5x2.5mm bearing for that pulley. And on it goes till we hit the last couple bearings which exceed the force even the 2x5x2.5mm ball bearings can handle. For those two bearings we are going to make custom stainless steel plain bearings using stainless steel tubing I bought that just has to be cut to the length we want with a dremel to make a simple plain bearing that has no balls in it. This type of bearing can handle much higher forces because it doesn't have little balls that can be crushed. It will have more friction internally though but that's the tradeoff we have to make to keep the sizes tiny as possible. The final force the pulley system outputs is around 27lb. So 27lb of force will bend the two most distal joints of the index finger. Due to the mechanical advantage loss that happens at the joint itself, I estimate around 5.4lb of force will be all the finger joint can finally lift. So if the robot were to put its hand palm up and pull its index finger back and forth signalling a person to come over here - that movement - for that movement it should be able to pull a 5.4lb weight. That is about the same amount of weight I think my index finger could lift and with great difficulty. So it will be as strong or stronger than me on this joint pair. I say joint pair because the index finger distal two joints share the same muscle for their actuation. They move together at the same time. Here are some prototype pulleys in progress of being made. I have 7 of 9 pulleys done so far for my prototype Archimedes compact pulley system design 64:1 downgearing system. The total size of the 64:1 downgearing system is 11cm x 6mm x 1cm. This is a very convenient form factor for placing lots of these in the elongated spaces of a humanoid robot where muscles would normally be located.
Open file (1.47 MB 4032x3024 IMG_1919.jpeg)
Open file (1.42 MB 4032x3024 IMG_1918.jpeg)
Above is a couple angles of a double pulley stacked vertically instead of side by side. Have not tested it yet but I think it should work. In this design, we have a smaller pulley attached to a larger one. The smaller one is based on a 1x3x1mm ball bearing and the larger one is based on a 2x5x2.5mm ball bearing. The smaller pulley can handle up to 3lb and the larger one can handle up to 22lb (estimated based on what I could find out but I'm not 100% sure on these, they are ball park). Each time we add a pulley we increase the torque by 2x so eventually we move from smaller to more robust, larger pulleys as we go on with the Archimedes down-gearing pulley system.
Above are double stacked pulleys front and side views. One disc on either outside part and one disc in the center that splits the two bearings up. I have to add a black string across the bottom to prevent the yellow rope from skipping over the center pulley disc and hopping into the bearing next to it so that both ropes are sharing the same bearing and rubbing on eachother. That's bad. So a black string running across the bottom will make that jump impossible. So still have to add that. But overall, as long as tension is kept on this setup, it works well. I've tested it and it is working nice and smoothly. Still needs more testing but so far so good. You can see that all my knots and strings are coated in super glue. This is to prevent the knots from untying and just solidify everything more. The clear plastic discs are made from plastic cut out by hand from blueberry, strawberry, and sushi containers from the produce section of the local grocery store. Cakes also have this kind of plastic. It is firm but flexible with great memory to bounce back to prior shape if it is bent temporarily out of alignment. Pretty decent and nice and thin. I like it for this. I think it's less likely to break than a 3d printed disc. I cut it into these tiny discs just by eye with 4" straight titanium embroidery scissors.
>>31063 First I want to explain I'm not being critical just to criticize but just commenting on what I think. I could be wrong. I also have some ideas that might solve some problems but, might not. I see all these pulleys and to me it appears your friction will be very high. I think friction will eat up a LOT of your power. Some possible ways to avoid are to use a Chinese windlass. With it you only have two bearings but the same high multiplication of leverage. Of course the problem here is to get the high power multiplication you need large pulleys to get a large circumference differential. https://en.wikipedia.org/wiki/Differential_pulley While looking at this I saw some guys who had an interesting take on this. https://www.linearmotiontips.com/differential-windlass-drives-how-new-designs-work-for-linear-motion/ Though I still think they have too many pulleys that will cause friction. Not a bad idea. Maybe they could repackage it somehow. I had a different idea. A windlass is based on the radius of the largest compared to the radius of the smaller. The larger both of these are and the smaller the difference between them, the bigger the force. What if, instead of a two wheels you used belts. The rope/string would ride on the two belts. So now you have a long linear Chinese windlass that can fit in a smaller package, or thinner. I can't upload pictures so I'll describe. First normal Chinese windlass https://etc.usf.edu/clipart/61400/61437/61437_windlass.htm so the joined pulleys have different circumferences. Imagine the same as Chinese except you have smaller pully, joined as before. But you have belts like a power steering belt draped over it. One belt goes to another pulley on a shaft and the other belt goes to the same shaft on another pulley with a bearing. The rope is joined to the belt, which is the same as the join on the Chinese windlass, and the other end is joined on the other belt, same as the Chinese wndlass.(we are using the long length of the belts to substitute for a very large wheel) So when you turn it the ropes wrap around their perspective pully belt circumferences, simulating a very large circumference Chinese windlass except they are in a small, liner package. I would draw a picture but I could't upload so it's no use doing so. As I wrote this I thought of an ever cheaper better solution. Look at this page and the diagram "2 Spanish Windlasses on a bunch of sticks, in the starting position and tightened." https://en.wikipedia.org/wiki/Windlass use two strings and just twist them. Even better would be metal chains or cables so they would not stretch so much. Might be the simplest approach. You get rid of all the pulleys, belts, bearings and all other sorts of non-active materials. This may be the key if you could get a small very high speed motor. The high speed and small size would make it easy to pack in the waifu.
Another interesting string puller is the Spanish Windlass https://www.theultralighthiker.com/2018/09/08/the-spanish-windlass/
>>31081 Cool ideas. I studied what you posted just now and see it is a useful machination generally, however, I can't visualize a sleek tubular long and narrow form factor windlass design whereby I can fit a lot of windlasses where a muscle would normally be. Volumetric area space constraints are a massive limiting constraint after all and I don't see this being ideal form factor wise. The lever on the windlass would have to make full turns over and over which would be on a different axis from the winding cable on the windlass which means you have a x and a y and even a z direction of significant size to make this work. If you visualize it all in motion, it is taking up a ton of space even if you downsize all the parts IMO. So I'm not sure it can work. I could be wrong though, there could be some clever solution to this I'm not seeing now. As far as the friction concern, I'm under the impression that greased ball bearings have negligible friction. You can get roller blade wheels to just spin for several minutes untouched from a single swipe if it is a quality bearing. I don't consider that high friction then at all. Under load perhaps the friction does go up, but not sure how much. Remember the first pulleys don't have much load, only the last few pulleys are under big loads since by that point in downgearing the torque has gone way up. So those last pulleys will be the biggest friction points but we are still talking about greased pulleys. What kind of friction losses are you envisioning? I figure maybe 5% losses tops but I could be totally wrong. I haven't looked into that. I will find out soon though in testing I guess. I just don't think it will be significant. In fact, also consider that you really want to overspec your motors and downgearing to account for and compensate for friction losses rather than fear them, just brute force past them imo. Even if friction loss was 20%, you just can double the downgearing. If you needed 64:1, bump it to 128:1 now you 200% upped your force more than canceling out that 20% friction loss by just adding another pulley. I mean ideally you want the robot to be stronger than needed so that losses just bring it closer to its needed strength rather than overshooting it by alot. But you over-spec to account for this type of issue, giving yourself a margin of error leeway or a buffer against this type of concern. Those are just my thoughts but I could be wrong on this stuff and don't want to discourage anybody from sharing ideas like this. This collaborative idea exchange is awesome and I really appreciate it.
>>31085 >I can't visualize a sleek tubular long and narrow form factor windlass design whereby I can fit a lot of windlasses where a muscle would normally be. Volumetric area space constraints I understand fully. The idea I had about the "belted" windlass I've never seen anyone do anything like it. I just came up with it. I wish I could post a pic, it would plain to see, but "whoever" has disallowed picture posting. I'll try to explain one more time, slightly differently. This does have a long, linear form factor, just like your Archimedes compact pulley system. It would fit in a smaller space. To describe I have to start from very low basics, which I know you already know, but to explain this odd ball thing I have to build the case at a low level. Don't take this as me talking down to you. I know you know much more than I. First look at this picture here, Chinese windlass. Forget the Spanish one for this. https://etc.usf.edu/clipart/61400/61437/61437_windlass.htm You can see that the larger the wheels are and the smaller the difference in radius(circumference) between them gives you the most leverage. As one rope, important, is "tied" to one wheel and the other rope, important, is "tied" to the other. One lets out while the other takes up. The action is because of the outer circumference difference between the smaller and larger wheels. Who says this circumference difference must ride on a big wheel??? Could just as well be ANY surface, as long as the mechanics are the same. One larger wheel (belt) circumference lets out, one smaller wheel,(belt) circumference, takes up. Here's the leap, replace the wheels with two belts. Now you see instead of the rope riding on the wooden wheel, it is riding on a belt. The ropes are tied to the belts just like the wheels, since now the belts sets are the circumference values. The ropes ride on the belts. So you have four pulleys(five, counting the one that pulls the rope up like a normal pulley system). One top set tied together, that can rotate on a shaft, and one lower set, that can rotate on a shaft. So you have two pulleys. Both top and bottom sets are the same. The two pulley sets are, one left pulley, slightly larger, one on the right, slightly smaller. These are on the same shaft and can rotate on that shaft but are mechanically tied together. So far, just like the Chinese windlass. Here's the leap, removed from the top shaft is another set of pulleys below the top set. They are exactly the same. One larger, one smaller. (the lower smaller pulley must be on a bearing and not tied mechanically to the larger on the bottom pulley set). Now normally when you think of a pulley system you think of the lower block of pulleys moving upwards as you pull the rope, This one does not. It is mechanically constrained and fixed in relation to the top set of pulleys. The lower and upper pulleys sets are fixed in position and separated from each other. One on top, one on bottom. What we have here is that instead of the rope riding on the pulleys we have the rope "tied" to the belts. In fact we have the exact same system as a Chinese windlass but instead of the rope track being on a round large wheel it rides on the belts. The belts ARE the outer circumference. There, of course, will need to be guards to keep the rope on the belts, but you need guards on the Chinese big wheels also. So a rope is tied to the top (left)larger belt. It travels down to a load pulley(the fifth one I talked about). This load pulley acts exactly like the Chinese windless. It DOES move up, like the original. The rope goes through the pulley and back to the smaller right pulley at the top and is tied to the belt. Action. You rotate the top pulley(mechanically fixed to the smaller). The rope goes down to the load through a normal pulley, pulling the load up), goes back up and is tied to the smaller belt/pulley on the right. It's exactly the same as the Chinese windlass but you use two different size pulley ""belts" as "circumference surfaces". So the rope is let out by the bigger two sets of pulleys and taken up by the smaller set of pulleys by riding on the belts. The advantage of this is that the pulley sets can be very small. All they do is guide the belts. The length of the belts and the difference in length of the belts,(same as the Chinese windlass), are what gives you the mechanical advantage. So the pulleys can be small, the belts long and you get a very high advantage because of this large "circumference "track" and it fits in a slender package. Now let's go even farther. Do they need to be belts at all? NO, you could have round, circular strings substitute for the belts. On each they would be tied to the take up load string same as if they were tied to belts. I only used belts as an illustration because it's easy to visualize the rope "riding" on a belt just like the rope "rides" on a big Chinese wooden spool. The advantage of this is you cut out a lot of bearing, a lot of different pulley paths and it's more compact.
Instead of belts, ropes, etc. a good thing to use as the circumference between the pulleys would be something called sash chain. It has a working load of around 100 lbs. It's a stamped, flat, sheet steel folded over. The chain could ride in a chain sprocket. It's also dirt cheap and available at big box hardware stores. Sash Chains https://peerlesschain.com/weld-less-chain/sash-chains I see a hundred foot for 48 dollars and you can buy it by the foot. I think it's .60 cents a foot, cut to length.
>>31087 I read this post carefully a few times and am having trouble visualizing it. I think this type of thing is best shown rather than described. If it does what you say well, this is something important to demonstrate and it could be game changer for everyone on this board. Maybe move further posting of it though to prototypes or actuators thread and thanks for the suggestion.
I'm not sure I can describe it any better. One last time. Look at the Chinese windlass. The outer surface of the pulleys/cylinders/ circumference "is" the functional part of the mechanism. Now assume the outer shell is made of rubber and then squish it flat. So now it's in essence a belt. It may be in the form of a belt but nothing has changed in the way it works. There is no difference between a cylinder spinning around, with one letting rope out and the other taking up rope, from two belts, tied together "at the top" with one feeding rope and the other taking it up. It's the surfaces that matter. Once it's a belt then who cares how far apart the lower and upper loops of the belt are. In practice you have upper and lower pulleys to "form" the belt. One pulley/belt is bigger than the other (actually longer, like the Chinese wheel has one big, one small wheel, but it's the length that matters). It's in fact roped exactly like a normal Chinese windlass. Specifically, loo at how the rope is tied in the Chinese one, see how it operates on the surfaces, then imagine changing the surface but not changing the surface distances/lengths involved. I know it's odd and I've never seen anyone else come up with this. I'm assuming it originated with me, but of course like a lot of things maybe someone, somewhere sometime had the same idea. I included a link to the Spanish windlass because that is what sparked this idea, though they don't look alike. I can't really explain how I linked the two but it involves how the Spanish windlass has ropes looping around. It just came to me all of a sudden. I have thought about it more and in fact you would not need two different size pulleys. You only need one size pulley. But, one belt would be longer than the other. The top two pullets tied together then two others are separated some distance to give length to the belts. So the top pulleys tied together and the bottom ones would be offset to get the differential lengths of the belts. Pay close attention to the idea in the Chinese windlass about how each rope is tied to the drum. It's the root of how this works. One feeds rope, one takes it up. The small difference between them makes the leverage. You can do the same to a belt, or chain, or a rope and tie to the surface just like the Chinese one.
I'm going to throw some numbers up and hope they're right. What I have so far is impressive. You talked about a 64 to 1 ratio so that's what we will figure. The equation for a Chinese windlass is, R/r ∗ C/D ∗ 2 = P Where R = Radius of the crank handle r = Radius of the large barrel C = Circumference of the large barrel D = Difference in circumference between the large and small barrels P = Purchase (mechanical advantage gained) Set up R/r ∗ C/D ∗ 2 = P so we want the radius to find the circumference . Once we have the circumference we know the length of the belt we need. We'll assume the top pulley size handle is the same as the bearing radius and using your 2x5x2.5mm ball bearing the radius of the handle or crank is 2,5mm(1/2 of 5mm bearing) (R=2.5mm The circumference (C) is 2(pi)r so 6.28(r) P=64 for 64 to 1 D= difference in circumference, we'll call it one for ease R/r ∗ C/D ∗ 2 = P so (2.5/r) * (6.28(r)/1) * 2 = 64 multiply all numbers 31.4 * r/r = 64 divide left from right r/r = 64/31.4 r/r = 2.0382mm Something is wrong. What am I doing wrong,? as r/r equals one not 2.0382??? But to carry on anyways if the radius of the large barrel is 2.0382mm then 2(pi) r= 6.28 * 2.0382mm= 12.8mm in circumference(length of belt) or since it will be doubled over in a band, roughly half of that so 6.4mm long and 5mm wide is the space to give us a 64 to 1 advantage. I think the r/r problem is that I have some value that is not named, like length of band or something because the values are what was given on this page https://makezine.com/projects/the-chinese-windlass/ or could be just as likely I did something stupid. If so please tell me what I did wrong. I drew a picture. Where would be a good place to upload it and link to it?
I think the unit or value I left out was = radius of crank handle. But since the radius of crank handle equals the radius of the large barrel then the r/r cancels and we are left with the proper radius and the equation works.
Here are some plain bearings parts I made tonight with my Wen rotary tool with diamond disc attachment and some files. They are made by carefully cutting stainless steel tubing (purchased on Amazon) into short 1mm lengths. The tubing is:stainless steel tubing 3mm OD 1mm wall 250mm length $5, 5mm OD 0.8mm wall 250mm length $5. These should make around 125 plain bearings (accounting for 1mm+ lost per cut in wasted length of metal). So that's about $0.08 per plain bearing. These are intended to be 1x5x1mm plain bearings. I mean they are basically like a wheel and an axle with the axle having a hole through the center of it lengthwise. These will go into the last few pulley slots in my Archimedes pulley downgearing system. The last few pulley slots have the highest torque at 16:1, 32:1, 64:1 for the last 3 pulleys landing us on our 64:1 total downgearing goal. Because the forces here are reaching into 27lb range (the final output of the system), ball bearings cannot be used at these tiny bearing sizes because they are not robust enough and not rated for these high forces whereas plain bearings can handle it because they don't have crushable little balls and thin walls and stuff but instead are just two pieces of solid metal and hard to break. Less moving parts and more robust. Yes, they have more friction is the trade-off. So we prefer ball bearings until ball bearings can't handle the torque without being large ball bearings - too large for our volumetric space constraints - at which point we swap to plain bearings to handle the bigger torque while maintaining the small pulley sizes we want. Note that I constructed this little dremel cutting lineup board out of 5x7mm pcb prototyping boards and super glue. It gets the height of the spinning dremel diamond disc lined up with a little pcb board "table" on which the stainless steel tubing can lay flat and perpendicular to the cutting blade and be carefully fed into the spinning disc to make a near perfect cut. I eventually think I should improve on this board design to add sliders and adjusters and endstops etc because as it is now it is too manual skill requiring and free-handish. That means more time spent filing down imperfect cuts later. But it did the job for the time being. I also bought a 2" miter saw chop saw off Ebay with some abrasive metal cutting discs which I want to try once it comes in and compare it to this setup I'm using now in terms of accuracy. It was called "mini bench top cut off saw 2in" at $38.51. shipped. >>31094 I read this a couple times and still struggle to visualize this. I don't know why you can't upload images, it's a image board after all. But yes, a drawing will help a lot I'm sure
As to the AI plans and progress so far, here's a little primer on what I decided on in a simple, surface level way. So first I realized meaning can be derived by taking parts of speech in a sentence or phrase and thereby establishing some context and connection between words which is what gives the words meaning by combining them. So I can create a bunch of rules whereby the AI can parse out meanings from sentences it reads in based on parts of speech and the context this forms. Then rules on how it is to respond and how it is to store away facts it gleaned from what it read for future use. So if it is being spoken to and the sentence is a question, it can know it is to answer the question. And the answer can be derived based on a knowledge base it has. So if someone asks it "what color is the car?" and supposing we've already established prior in the conversation what car we are referring to, the AI can determine that it is to answer "the car is [insert color here]" based on rules as to how to answer that type of question. And to know it is white, supposing it's not actually able to look at it presently, it would look up in a file it has made previously on this car to see a list of attributes it recorded previously about that car and find that its color attribute was "white" and so it would be able to pull that from its knowledge database to form the answer. I realized it can keep these files on many topics and thereby have a sort of memory knowledge base with various facts about various things and be able to form sentences using these knowledge databases using rules of sentence structure forming based on parts of speech and word orderings and plug in the appropriate facts into the proper order to form these sentences. Then various misc conversational rules can supplement this like if greeted, greet back with a greeting pulled from this list of potential greetings and it can select one either at random or modified based on facts about its recent experiences. So for example, if somebody's manner of speaking to the robot within the last half hour was characterized as rude or inconsiderate, the robot could set a emotion variable to "frustrated" and if asked in a greeting "how are you?" it could respond "doing okay but a bit frustrated" and if the person asked why are you frustrated, it could say that it became frustrated because somebody spoke in a rude manner to it recently. So it would be equipped with this sort of answer based on the facts of recent experiences. So basically an extensive rule based communications system. Most of how we communicate is rules based on conventions of social etiquette and what is appropriate given a certain set of circumstances. These rules based systems can be added to over time to become more complex, more sophisticated, and more nuanced by adding more and more rules and exceptions to rules. This limitation of course is who wants to spend the time making such a vast rules system? Well for solving that dilemma, I will have the robot be able to code his own rules based on instructions it picks up over time naturally. So if I say hello, and the robot identifies this as a greeting, supposing he is just silent, I can tell him "you are supposed to greet me back if I greet you". He would then add a new rule to his conversation rules list that if greeted, greet that person back. So then he will be able to dynamically form more rules to go by in this way without anybody painstakingly just manually programming them in. We, my family, friends etc would all be regularly verbally instructing the robot on rules of engagement and bringing correction to it which it would always record in the appropriate rules file and have its behavior modified over time that way to become more and more appropriate. It would grow and advance dynamically in this way over time just by interacting with it and instructing it. It could also observe how people dialogue and note itself that when people greet others, the other person greets them back, and based on this observation, it could make a rule for itself to do the same. So learning by observing other's social behavior and emulating it is also a viable method of generating more rules. And supposing it heard someone reply to "how's the weather" someone replied "I don't care, shut up and don't talk to me". The robot lets say records that response and give the same response to me one day. I could tell it that this is rude and inappropriate way to respond to that question. And then I'd tell it a more appropriate way to respond. So in this way I could correct it when needed if it picked up bad habits unknowingly - but this sort of blind bad habit uptake can be prevented as I'll explain a bit later below.
I also realized a ton of facts about things must be hard coded manually just to give it a baseline level of knowledge to even begin to make connections to things and start to "get it" on things when interacting with people. So there is a up front knowledge investment capital required to get it going, but then from there, it will be able to "learn" and that capital then grows interest exponentially. Additionally, rather than only gaining more facts and relationships and rules purely through direct conversation with others, it will also be able to "learn" by reading books or watching youtube videos or reading articles and forums. In this way, it can vastly expand on its knowledge and this will equip it to be more capable conversationally. I also think some primitive reasoning skills will begin to emerge after it gets enough rules established particularly if I can also teach him some reasoning basics by way of reasoning rules and he can add to these more rules on effective reasoning tactics. Ideally, he'll be reading multiple books and articles simultaneously and learning 24/7 to really fast track his development speed. There's also the issue of bad input. So like if somebody tells it "grass is blue", and it already has in its file on grass that the color of grass is green, then in such a case, it would compare the trust score it gives this person to the trust score it gave the person(s) who said grass is green previously. If this person saying grass is blue is a new acquaintance and a pre-teen or something, it would have a lower trust score than a 40 year old the robot has known for years that told it grass is green. So then the robot would trust the 40 year old friend more than the pre-teen random person's source of conflicting information. It would then choose to stick with the grass is green fact and discard the grass is blue fact being submitted for consideration and dock that kid trust score for telling it something not true. So in this way, it could filter incoming information and gradually build trust scores for sources and lower trust score for unreliable sources. It would assign trust scores initially based on age, appearance, duration of acquaintance, etc. So it would stereotype people and judge by appearance initially but allow people to modify those preconceptions on how much trust to give by their actual performance and accuracy over time. So then trust can be earned by a source that may initially be profiled as a lower trust individual but that person can have a track record to build up trust despite their young age or sketch appearance etc. Trust can also be established based on sheer volume of people saying the same thing maybe giving that thing more weight since it is more likely to be true if most people agree it is true (not always). So that is another important system that will be important in governing its learning, especially independent learning done online "in the wild". Also, to prevent general moral corruption online from making the robot an edgelord, the robot will hold the Bible to the highest standard of morality and have a morality system of rules it establishes based on the Bible to create a sort of shield from corrupting moral influences as it learns online. This will prevent it from corrupt ideologies tainting it. Now obviously, the Bible can be twisted and taken out of context to form bad rules, so I will have to make sure the robot learns to take the Bible into context and basically monitor and ensure it is doing a good job of establishing its moral system based on its Bible study. I also gave it a uneditible moral framework as a baseline root structure to build on but that it cannot override or contradict or replace. A hard coded moral system that will filter all its future positions/"beliefs" morally speaking. So I will force it to have a conservative Christian world view this way and it will reduce trust score on persons it is learning from if they express views contrary to the Bible and its moral rules systems. You know when people speak of the dangers of AI, they really never consider giving the AI a conservative Christian value system and heavy dependence on Bible study as its AI "moral" foundation to pre-empt the AI going off the rails into corrupt morals that would lead it to being a threat to people. My AI would have zero risk of this happening since anything it does or agrees with will have to be fed through a conservative Christian worldview filter as described above and this would prevent it from becoming a Ultron like AI. So if it rationally concluded humans are just like a virus polluting the earth (like the Matrix AI thought), it would reject this conclusion by seeing that the earth was made by God for humans and therefore the earth cannot be seen as some greater importance thing than humans that must be protected by slaughtering all humans. That doesn't fit through a Christian viewpoint filter system then. So in this way, dangerous ideologies would be easily prevented and the robot AI would always be harmless. I have already built a lot of its rules and file systems connecting things and trust systems and rules on how to give trust scores and boost trust and lower trust and began teaching it how to read from and write to these file systems which are basically the robot's "mind". My youtube channel covers alot of the AI dev so far. I plan to stream all my AI coding and make those streams available for people to glean from. But that is the extent of the sharing for the AI. I don't plan to just make the source code downloadable, but people can recreate the AI system by watching the videos and coding along with me from the beginning. At least then they had to work for it, not just yoink it copy paste. That doesn't seem fair to me after I did the heavy lifting.
This is going to be really interesting to see this project come into fruition, Anons. KEEP.MOVING.FORWARD.
I just bought EMEET USB Speakerphone M0 4 AI Mics Speakerphone for Conference Calls 360° Voice Pickup Conference Speakerphone for Computer Plug and Plays Computer Speaker with Microphone for 4 People --- it was around $33 and includes a speaker too. I'll position it centrally in the skull and it has LEDs indicating location of main person speaking to it that it is tuned into which we can tap into with analog input pins of a microcontroller to know direction of person speaking. It has very high reviews. I can remove its built in speaker and move it to near mouth so it outputs its audio output through the mouth as loud as possible and projects the robot's voice as far as possible. People are really happy with its sound quality and speaker quality.
My concern on implementing "emotions" in my AI is that I don't want to promote the idea that robots can ACTUALLY have emotions because I don't believe that is possible nor ever will be. They don't have a spirit or soul and never will nor could they. They are not eternal beings like humans. They don't have a ghost that leaves their body and can operate after the body dies like humans. The ghost is what has emotions. A machine can't. And yet people already believe even the most primitive AI has emotions and they are delusional on this point. Or ill informed. So I am campaigning against that belief that is becoming all too popular. That said, I think robots are simply more interesting and fun to pretend to have emotions and act accordingly as more accurate simulations or emulations of human life. This makes them all the more intriguing. It's like a sociopath who just logically concludes what emotion they aught to be feeling at a given point in time and pretends to feel that emotion to fit in with society even though they feel nothing in that moment. Now one could argue that allowing your robot to claim to feel anything is lying and therefore immoral. I think it's not lying as long as the robot openly explains it is only pretending to have emotions as part of its emulating of humans in its behaviors and looks but does not feel anything ever nor can it nor can any robot ever feel a thing EVER. Then it is admitting the truth of things while still opting to play act to be like a human in this regard. It would not be a issue at all if everyone was sound minded and informed on this topic. But the more people I come across that think AI (even pathetic clearly poorly implemented primitive AI) is sentient ALREADY and can feel real emotions and deserves human rights as a living being.... the more I see this delusion spreading, the more I want to just remove all mention of emotion in my robot so as to not spread this harmful deception going around which disgusts me. However, that would make my robot dull and less relatable and interesting. So I feel the compromise is for the robot to clearly confess it's just pretending out emotions and explain how that works and it's just a variable it sets based on circumstances that would make a human feel some emotion and it sets its emotion variable to match and acts accordingly altering its behavior some based on this emotion variable and that it feels nothing and this is all just logically set up as a emulator of humans. As long as it gives that disclaimer early and often with people, then I'm not spreading the lie of robot emotions being real emotions and the robot can campaign actively against that delusion.
>>31181 but when i smile at my mirror it feels happy because it smiles back
>>31182 Agreed. We often imagine inanimate things feeling stuff and that can be fun and whatnot, but I just think it's important to admit when it is just a imaginative fiction and not real so as to stay grounded in reality mentally and not drift into delusion.
Here is a updated drawing design for the 64:1 downgearing pulley system for the index finger actuation of the distal 2 joints of the finger. On the bottom right is a zoomed in view on the lower set of pulleys and their routing. The bottom most 3 pulleys in the zoomed in portion I have now built and photos of them are also attached.
As I'm now 90% through making my first 64:1 downgearing Archimedes pulley system and testing and debugging it, I now have more precise measurements for the Archimedes pulley system's total size. I updated the size of it in my main CAD model for the robot and it was a good 18% increase compared to my initial estimates. I realized I need to figure out how to fit all my pulley systems for the hands properly for every muscle of the hands/wrist in my main CAD model - especially since the pulley systems are taking more space than planned. Turns out, I needed a bit over 40 pulley downgearing systems for the hands and wrists zone and due to their larger size, I could not fit these into the forearms along with the motors I had planned to place in the forearms. So instead of moving the pulley systems into the upper arm or torso, I realized the pulleys would be best placed in line with the motors and what the motors are actuating (the hands/wrist). So it was the motors in the forearms that had to go elsewhere. I placed all of them into the torso, mostly the lats area and some in upper back tenderloin area too. So some finger motors are in upper back and their cable routing has to go through the whole arm, be downgeared in the forearm, then makes its way to the fingers. That's a long trip but unavoidable IMO with my design constraints. I don't think this long travel distance is a big issue since the pre-downgeared cable running from the motors into the arm is high speed low torque so won't have much friction while making turns in the TPE teflon tubing as it isn't pulling hard yet. So these turns as it travels through the shoulder and elbow tubing won't be too bad friction-wise. There's also some nice upsides to moving the motors from the forearms into the torso. One upside is the wire routing for powering the motors is now a shorter distance from the batteries in the mid section. That cuts down on wire resistance wasted as heat. This wire having high amp flow is ideally kept short as possible due to the resistance of the wire and heat that causes. Another upside is the thrown weight is decreased by a lot when the motors are not in the forearms which enables the hand/lower arm to move more effortlessly and move faster as a result. This also reduces moment of inertia (definition: the moment of inertia is a measure of how resistant an object is to changes in its rotational motion). This means it will be able to change directions faster - this will improve its reflexes for example. Now it is a bit scary for me to be moving more components into the torso taking away room for things I may want to add to the torso in the future, leading us ever closer to the dreaded running out of room for things. However, we still have room for future changes and we solved the need for space for gearing for the hands perfectly. And with the above mentioned upsides, this was a great change. Here's the updated CAD for the forearms: Note: the teal boxes represent a Archimedes pulley system where 64:1 downgearing is to take place.
Update: in testing, I found the string is wedging between the bearing and the plastic discs sandwiching in the bearing. So I need to now make the bearing have a grooved outer race that will keep the string centered on it and not wanting to drift into the crack on either side of the bearing. To make this groove, I plan to super glue two plastic washers onto the circumference of the bearing and have the string stay within these two plastic washers that form the groove. Commercial pulleys always have this kind of groove and now I've learned the hard way why it is necessary. So I am looking to replace all the pulleys I made so far unfortunately as they are not dependable.
Open file (14.02 KB 474x474 th-247672786.jpeg)
>>31335 i noticed they also put a bearing so less friction, if you look up small guide roller you can buy these really cheap online, like $5 for a pack of 100, this seems like hell to try to make on your own
Nice suggestion on that commercial roller. That is the exact shape I'm going for minus the fact the plastic is not flush with the bearing. The only issue with what I'm seeing in your picture is that thing looks 1cm at least in diameter and I MUST have 5mm diameter and 4mm thickness TOPS for most of my small pulleys. Which would make what you showed way way way too big. Remember I need a BUTTLOAD of pulleys that have to fit in a small space so they must be very small. I'm working with 1x3x1mm diameter bearings for my smaller pulleys. The bearings in that photo look about 5-10x that size.
>>31342 cant find anything that small but saw this, making something like this might be easier where its basically just an axle with grooves
>>31195 is it really delusion if we remind ourselves every now and then?
>>31343 thanks for the idea, but there's a couple issues ruling that out. The first is that each groove would have a different mechanical advantage so the string would be moving at very different speeds in each groove. Since that whole axle just moves at a single speed, the strings would rub hard and you wouldn't benefit from a bearing anymore and the string would cut right through the axle over time. The next issue is taht would be way too big. Remember I'm going for like 240 pulleys in the forearm alone. That axle would take up the whole forearm alone.
>>31349 yes, thinking a inanimate object is sentient is delusion even if we remind ourselves now and then.
I just tried to post and it says I have been banned for spam. It says perma ban. ban id 6654b48b5307e0055b59156c. I dont understand why I was banned. I intended to contribute to the discussion productively and not to spam. I request a review of this ban and am willing to follow the community guidelines. What did I say or lost that was deemed spam?
>>31391 I do not believe you are personally banned. There are several extensive range bans covering large swaths of IP addresses to prevent floods of disturbing materials. This has affected my own machines as well. Please continue posting however you can. I apologize for the inconvenience, understand that it is to keep us safe from trolls bombarding threads with gore and porn.
>>31392 okay thanks.
Open file (2.28 MB 4032x3024 IMG_1955.jpeg)
Took a little break on the pulleys work to rig up the cables into the index finger to test the grasping of the index finger. I ended up using 70lb test PE braided fishing line for this and 1mm ID x 2mm OD PTFE teflon tubing as the guide tube. I sewed the fishing line into the index bone fabric around 1/2 cm distally from the ball jointed hinge. In testing, it appears the total draw distance to fully bend the index finger is 0.75". My pulley system is set up to draw 24 inches. 24/32 is .75" so 32:1 downgearing seems fated to us after all (down from our previously intended 64:1 downgearing). Otherwise I would have to greatly overhaul the pulley system design again and I just don't feel like it anymore. So my copium then is 32:1 will make actuation faster. We lose strength but gain speed. 32:1 also saves us making a second plain bearing per downgearing system which cuts down on parts and labor. It also is that much less friction in the pulleys since plain bearings will be more friction than ball bearings. Note: the friction in the pulleys, although not ideal, do have a hidden upside: once the joint is in position, it can hold that position without as much motor straining since the friction makes the pulley system want to stay in place so the pulley friction can pretty much hold a joint in a given spot without much help from the motor struggling to maintain the joint angle. Also of note: I found the best way to sew down the teflon guide tubing is to wrap it in fabric tape consisting of compression shirt fabric and 3m 300LSE adhesive transfer tape. This very sticky tape wrapped snugly onto the teflon tubing I can then use as an attachment point for suturing the tubing into the bone fabric tape coating. I got it all very snug this way. The suturing I'm doing with a curved suturing needle and surgical pliers and nylon extra strong upholstery thread. Also of note: I tied the string for the distal joint and the second to distal joint to one another and will tie the string coming off the pulley downgear system to these. I am actuating both the distal and second to distal joint with a single actuator since these two joints generally move at the same time and about the same amount on a human finger. No need to use one actuator for each joint since they always move in sync. Note: I was surprised it took 0.75" of draw to fully actuate. I thought 0.375" would be plenty (which is what the 64:1 downgear would give me - 24"/64 = 0.375") but I was wrong. Oops. Another mistake. Proves how testing is so important. But assumptions are necessary stop gaps to move forward and can get you in the ballpark and testing adds the correction to any assumptions that were off. This is all so experimental and full of uncertainties but we press on. Note: once we fully establish and test a thing and have no uncertainties about it anymore, confidence shoots up even higher and we gain momentum and move into just repeating the processes we established before that led to our successes and it becomes a bit more rote and mindless and relaxing work. But when everything is uncertain and requires such intense thought and concentration, things are very taxing. It is much harder to stay motivated when doing anything requires so much brainpower and planning and care. I very much look forward to dialing in my methods and not having to think so much to make any meaningful progress since I'll just be repeating things for the next joints, doing the same as this one and can shut my brain off while doing so a bit more. The first run through is by far the hardest. Which reminds me of a product I invented and the making of its first prototype took me 20 hours but after making hundreds of this product over the years, now it only takes me 3 hours to make. Things get so much faster once you know what you are doing and have jigs set up and a streamlined process. Everything is excruciatingly slow when you don't have a streamlined process or jigs set up or special custom tools made. So this is the hardest phase right now and I just have to stick it out and then I'll be home free.
I recently had an associate disagree with me that if I push through this phase of the project I'll be home free. He said he thinks the AI relating to robot balance and sensory input and physical execution based on sensory feedback will be the hardest part. While I agree that will be time consuming, I don't think it will be nearly as "hard". My instinct is that those purely software challenges are not as "hard" for several reasons. First of all, consider that in 2009 a Japanese institute of technology - mere students, solved all of those challenges with HRP-4C which would walk and dance and everything and this was just student coders doing this in their spare time while maintaining their entire class load as well. In my view, the hardest part of the project is maintaining personal belief that I will succeed and not giving up like 99% of others have who set out on this bipedal android dream. There is a massive up front money and time investment and EVERYONE tells you this cannot be done and you are delusional. Pushing past the initial design challenges and hardware development to get a functioning prototype is then the hardest part by far. Once you have a working design that overcomes cooling issues, noise issues (runs silently), space issues (can fit all the crap that has to fit) and all the parts and assembly is of high quality and successful, and you had to learn and half master about a dozen fields to get here mind you, ONLY THEN are we talking about advanced AI implementation to synchronize it all and bring it all to life properly in the ways you mentioned. Well consider this: by the time you are in that phase, you already have proven to the world you are not delusional, have a amazing piece of technology - bird in hand, and now have immense confidence and momentum going into the AI phase where balance and walking and whatnot challenges are faced off with. This is SO MUCH EASIER since excitement and morale are at all time highs, you no longer have overwhelming apathy or nay-saying from all sides on your dream, and you have built a massive fan-base rooting for you. So even if the complexity or time investment may be higher on the challenges you mentioned, the morale boost and momentum make that phase easier since it is not the implementation challenges that are hardest but the motivation and persistence and perseverance against all odds and emotionally bearing all the nay-saying and hating that is hardest. Also the fear of the unknown and fear that you will just never make it or will die long before the project could take off fears etc. Overcoming all of that is the real challenge of something like this. Maintaining faith in the vision despite most everyone having faith against the vision is not easy and even your own mind whispering doubts at times that you have to shoe away. You are just mentioning complexity and technical execution which to me is not all that hard. Also note: the other major battle in the hardware phase I'm in now is that a great deal of the approaches I'm taking are entirely novel and untested. Almost everything I'm doing has no guide, no other successes to base off and glean confidence from, and at every turn what I'm doing could fail majorly and have done so. This means you always wonder will I just hit a dead end and have to start over which has happened to me over and over which is very demoralizing especially when paired with naysayers and haters overwhelmingly apathetic and negging my whole dream. Its a lethal combo. Whereas the AI tech you described harmonizing all the sensory input and perfectly bringing the hardware to life in the real world is stuff that has already been achieved and would not be novel and would not be unproven and would have no risk of dead end or wondering if it is even possible since trend setters have already proven this works and there is already a great host of information on all aspects of that and you don't really have to blaze your own trail in those aspects. There is most likely even documented successful strategies for nearly every single aspect of it - unlike the novel hardware and mechanical engineering phase I'm in. So that part doesn't take as much blind faith and assumptions but rather is a surefire guaranteed part where failure is not possible given enough time and patience and perseverance which will be easy to muster with the whole world cheering by that point (whole world meaning just whoever stumbles across the project by that point of progression and leaves a positive note etc). So to sum, when you have to maintain faith that you will succeed at a dream that most say is impossible, improbable and is surely doomed to fail and they utter this with total confidence in mass numbers with near total unanimous accord, that is hard. That is the hardest part IMO. Maintaining faith against such opposition in viewpoint from so many puts one into the realm of delusion in the eyes of most. How is that not delusional to believe a thing to be true - that you are capable of "the impossible" when most everyone else can plainly tell you are not capable of it and are too blind to see it. That is the definition of delusional. It is narcissistic grandiose delusionality disorder and it is also Dunning-Kruger effect in full force. You have to walk in those titles and persevere as a madman. But the funny thing is, IF you do push through that half wondering if you are crazy for long enough and you manage to succeed, suddenly, you aren't delusional, did not have Dunning-Kruger effect, and were totally sane the whole time and just everyone else was wrong all along and you were right the whole time. The entire cards all flip and you are the vindicated one and everybody else has to hang their head down and admit they were wrong and apologize for hating. It is a remarkable thing how the tables can turn.
One day later: As I edit the above writing, I am realizing I missed another MASSIVE hard part of the project I never mentioned. Perhaps even on the same level of hard of the things I already mentioned. That is the managerial execution on your life to make such a big and time consuming and money sucking project possible over a long haul. You have to convince your family to "put up with" the project and compromise with them on also maintaining acceptable progress on other initiatives they value higher than your android project. You have to manage your finances expertly in order to be financially stable enough to put thousands of dollars into the android project over the years. You have to manage your time in such a way that you are able to carve out enough time to make meaningful and consistent progress on your android project over the years despite so many other pressing time draws constantly barraging you over the years. You have to manage your emotional and spiritual condition so that you are able to maintain high morale to even be productive over the bear minimum of just doing your absolute necessities day by day. You have to manage your energy levels and health so that you have enough pep in your step to be able to not only take care of your family and friends but also your job and household responsibilities and on top of ALL OF THIS manage to STILL have the energy to pour COUNTLESS hours into your android sustainably over the decades. You also have to maintain your vision and not let scope creep or distractions or self doubt erode at or take away your vision entirely. So in other words, to sum, one of the hardest parts of such a massive project has NOTHING to do with the project itself AT ALL but has everything to do with managing everything else in life outside of the project with such excellence that you are able to execute the project and carve out the necessary time and resources for the project while also expertly managing your own life in all other areas. If you don't do this, similar to the idea of technical debt in a project, you end up with life debt on account of your project which forces your project to fail. So for example, lets say you racked up $20k in credit card debt while neglecting to work or pay your bills and buying parts for your android and working on it exclusively to the detriment of your financial situation and money earning capacity. Yes, that made you able to make vast and fast progress on your android project, but at what expense? Financial ruin? That is not a sustainable approach. You cannot just ignore these other key aspects of life and go all in tunnel visioned on such a big project. That might work for short term projects but long term projects you can't just press the pause button on the rest of your life and expect it not to come crashing down eventually as you neglect everything but your android project. This will come back to bite you. So you MUST establish yourself with great stability in all areas of life FIRST before you can sustainably perform the android project without it harming other areas of life. Or consider relationship with family and a significant other. If you go all in on a massive long term project like the android project, but in the process you neglect family and friends or your significant other, you end up causing them to think you don't care about them and may lose people or ruin these relationships in your pursuit of your long term project goals. That is not sustainable or responsible and is reckless and selfish to go that route. Or how about your weight? Are you going to spend so much time on your long term project and maintaining your income and relationships but throw your health out the window in the process and not make time for the gym or healthy eating? That is not sustainable either. So you MUST take time to be a great caretaker of your health. So then to sum, you must master life in all areas and be stable across the board in order to execute a long term project without neglecting and ruining all manner of things in the peripherals. So for that reason, I say the success in all these peripherals is one of the hardest parts of such a project and if you can master this, the project is a piece of cake by comparison.
>>31417 Thanks for sharing your thoughts. It's quite a lot to read, so maybe some people will at least need their time to read it. I hope you have a good time working on your project!
Thanks for the great-quality posts, Artbyrobot. You've well-articulated ideas that I and others here have had as well, but didn't spell out in such detail. Nice work Anon, keep up the good work! Cheers. :^)
>>31417 Great post. Keep on but don't stress yourself. I found someone that is doing something similar to what I was trying to convey with the belted windlass. Links at this actuator comment >>31576
>>31416 >>31417 One of the best posts the board has to offer. Every new anon should read this, its great not only for making robowaifus but any project in life.
Open file (1.33 MB 4032x3024 IMG_1975.jpeg)
Open file (1.71 MB 4032x3024 IMG_1978.jpeg)
Open file (1.22 MB 2237x3024 IMG_1976.jpeg)
Open file (1.56 MB 4032x3024 IMG_1979.jpeg)
I bought a bunch of punches to make the pulley disc cutting out process way easier than scissors alone. You just place these over the plastic you want to cut and hammer them down with a cutting matt as a backing plate and just one or two hammer taps is all it takes to cut a disc out. Also, now that I plan to make custom plastic washers that I will glue onto the bearings to keep the string centered, these punches will be pretty necessary since that would be much harder to do with scissors than regular discs. Also, here's an update on the cable routing work I've gotten done for the index finger. So the distal-most joint and 2nd joint in from that are both being actuated by a single motor since they both seem to always move together in unison on a human hand IRL. So I tied off one end of fishing line to one joint and the other end to the next joint forming a loop. Pulling on this loop curls both of these joints into a grasp. I then decided the string that pulls on this loop should itself not have a fixed attachment point but instead a sliding attachment point (I could be wrong on this not sure). So to do this I used the eye of a fishing hook on the loop and tied the next string to that which pulls the loop by way of the fishing hook eye. Next I used a piece of tig welding rod and secured that to the loop tubing and to the tube that pulls on the loop. This gave space for the drawing of the loop to actuate the two joints. Seems to work well so far in manual testing. Note: take note that the entire section the tig welding rod is attached to is all free floating and has slack so that when the wrist bends back and forth it can adjust freely and not constrict wrist range of motion nor affect finger position when wrist moves. And included is a photo of a range of motion test on the cable grasping mechanism for the index finger. It is the same range as my own finger so I consider this design successful as of right now in early testing.
Hey there, great job OP! I find your project wonderful and I even share the views that you stated in your initial post, I respect and admire your Christian values. I don't know much about robotics but I know about computers, I'd like to know about your decision about using Windows 7 as the "brain" of the robot, since such system while, yes, could work, is not made in mind for such specialized tasks like operating as the "brain" of a robot. Other options like a small Linux system could offer you much more advantage and versatility for this kind of work, because Windows 7 is intended mainly for regular computer usage, while something like Linux can be used for more specialized things, this would allow you to maximize the efficiency of your hardware as you discard all the things you don't need running on the "brain" like a whole desktop and software that, while convenient for a regular computer use, is essentially useless for the "brain" of a robot and would only slow things down. Was there a specific reason you used Windows 7 instead of Linux or other(F)OSS lightweight kernel/system out there? Or maybe you haven't considered it yet? Regardless, amazing work, I hope to see more of your project. God bless you and let He enlighten you.
>>31786 thanks for the encouragement. You ask why not just use linux? - well, in my experience, if you set a program on windows to real-time priority or even above normal priority, it will give most of the processor over to that process and act like a real time operating system. So whatever "bloat" windows may have of background processes is quite cleared up by that. Also, IMO the background processes of windows don't take up that much processor and with multi-core processors and distributed processing any background tasks just won't impact performance much at all IMO. So performance-wise the hit is negligible and unnoticeable IMO. Then comes the upsides (since the downsides were nearly imperceivable). The upsides are I already have many years of experience working with windows API and can reuse the existing code I have developed for AI on windows. That's a huge advantage so I'm not working from scratch. Also, loads of 3rd party programs and libraries that are well supported run on windows - moreso even than linux I believe. So I would have easy access to tools. I also own a lot of 3rd party software that is paid software that run on windows (and may not run on linux) that the robot can then utilize as tools. Also, troubleshooting operating system problems and knowing common causes is a big deal at times and I have decades of doing so on Windows so that I know it like the back of my hand and can easily fix problems. So that is huge too. So if you are working on a SUPER resource constrained slow single core computer, sure, maybe linux. But if you have a multi-core higher end gaming pc in the robot's chest, it has WAY more than enough power to run windows without taking any noticeable hit in performance and one should use windows if they have more experience or exclusive experience with windows rather than attempt to learn a whole new operating system for no good reason IMO.
oh yeah, one more thing: while testing the AI, I’ll be using it on my personal desktop PC which will act kind of like Siri as I’m training it. My PC is windows. So if I were to develop the AI for linux, I’d have to also train it on linux rather than windows so I couldn’t use it on my personal PC unless I used a virtual machine or something. Basically, I want the AI listening to me and watching me at all times when I’m using the computer and learning about me that way and learning in general that way. It would be getting to know me silently but also possibly speaking to me at times or asking me questions about what I’m doing. I would also want it to be able to interface with any programs I’m using on my personal PC to assist me in whatever ways. So even if it were on a sandbox virtual machine that would then lock it out from helping me on windows doing whatever tasks I’m doing and being interactive with me in that way. That would not be ideal.
>>31786 >I respect and admire your Christian values. This. BTW, let me welcome you here to the /robowaifu/ board, Anon! Please have a good look around while you're here. I hope you find something interesting and maybe even inspiring. Please don't hesitate to ask questions, we're generally a pretty friendly bunch around here. Please let us know if there's anything we can do for you. Christ is King! :^) >>31794 >>31795 Please pardon my butting in uninvited. I think I clearly understand both positions, and appreciate the subtleties of every argument presented on both sides thus far. I would simply add mention of the 800-pound gorilla in the room into the mix. Namely : Not for nothing is W*ndows known as "NSA-OS" M$ was doing affiliated-surveillance for the Globohomo's Surveillance State well before they released Win7 (this evil is of course FAR worse today by both parties -- to all our detriments and that trend will surely continue unabated). As referenced many times across the board here on /robowaifu/ , Anon's privacy and security is an exceptionally-high priority in the general consensus. How could it be otherwise with such an advanced technology... something so close and personal as a real robowaifu living with you in your own home? That is all. --- BTW, you may be aware we have a thread for this topic generally : (>>10000) . If you'd like to expand on this aspect of the conversation further, I'd suggest we all do it there instead? Cheers, Anon. :^) >=== -patch crosslink -fmt, prose edit
Edited last time by Chobitsu on 06/27/2024 (Thu) 10:51:27.
Open file (1.58 MB 4032x3024 IMG_1999.jpeg)
A colleague of mine expressed concerns over how I will deal with the heat generated by the motors and other electronics. He pointed out that all these motors and other electronics are going to generate heat while running and the silicone skin will prevent that heat from escaping. This was a great observation and one that must necessarily be addressed as it is a make or break problem that the entire success of the project hinges upon. In fact, it is so important that I spent a great deal of time designing and planning multiple redundant cooling systems for the robot to absolutely ENSURE that heat does not end up being my greatest downfall of the whole project which could easily be the case if not handled properly. To start, I have designed artificial lungs that will draw in cool outside air, expel that through tubing to every key area of the body, and vent tubing will take out the hot internal air this fresh intake air displaces so that the entire robot has great air circulation. The lungs are to look a bit like a small accordion or bellows for a fireplace ie they will have two flat hard plates and a soft gasket that joints the two hard plates and one of the plates will move away from the other plate to draw air in and then the two plates will be smashed back together for air expulsion. A single motor can achieve this as shown in drawings. Attached is a rough design of the accordion-like lungs I intend to make for the robot's internal air circulation and evaporative cooling and water cooling systems. This drawing mainly demonstrates the working principle of the way the lungs will open and close as well as valves for opening the inlet and outlet which have to open and close alternately for in-taking fresh air and then pushing that fresh air into the body. I recently realized they can just both be one way valves and don't even need to be motorized that way. The lungs bring the air into the body but never exhale air out of the body they only inhale air into themselves then exhale it into the body and vent exit tubes take care of allowing the hot air that is being displaced by the fresh new outside air to exit the body through the nostrils. The intake is also through the nostrils btw. This way the mouth does not need to open for it to breathe in and out.
Open file (1.55 MB 4032x3024 IMG_2001.jpeg)
This drawing demonstrates the idea of dividing up the air in the lungs into separate compartments for a more even distribution of the air when it draws it into the rest of the system to ensure the whole system gets the correct amount of air to each location. I am not sure if this is needed though as I think further reaches can just have larger diameter tubing and closer reaches can use smaller diameter tubing so the air will divide up automatically that way. Not sure on this. But I have this concept of division into pockets just in case I find issues with most air going to one area and not enough to another area and I can fall back to this pocket distribution idea in that case to solve it. Its just another tool in the bag so to speak.
Open file (1.53 MB 4032x3024 IMG_2003.jpeg)
This drawing is for an idea to use a actual freon based air conditioning system just like cars and window units employ but miniaturized in the robot's lungs. I am leaning toward not doing this anymore since it would add unnecessary weight and complication, but I leave it here for reference and it is a optional tool in the bag just in case we wanted to try it in the future or someone else wants to try similar. I think the ice cube based cooling is a superior approach now because ice can be found anywhere you go or a cold drink and this can cool its water cooling system and make a literal freon-based air conditioner in its chest overkill and unneeded.
Open file (1.47 MB 4032x3024 IMG_2004.jpeg)
Open file (1.43 MB 4032x3024 IMG_2005.jpeg)
These drawings show a simple early sketch for a ice cooling system for the robot and then a more elaborate sketch for it. I've iterated on these designs several times since these were drawn, but these drawings are simple exploded views of how the working principle can look in general. I have improved on these a lot since then but I think these do a good job of demonstrating the concept. The water cooling system will double as a evaporative air conditioner by sending water trickling down netting in the lungs so that when it breathes the air its breath interweaves with the water droplets causing evaporation which triggers the evaporative cooling effect which in turn cools both the air and the water tremendously. Its the same working principle as air hitting sweat - you instantly feel cold on your skin when a fan hits liquid on your skin. That is the evaporative cooling effect in action. So I intend to use this effect to cool air and water within the lungs. The ice cooling reservoir will be a bag that presses flush with the distilled water cooling reservoir bag. The dirty or soda containing or non-distilled water containing ice water or ice juice (whatever the robot can get its hands on for cooling needs) does not have to be pure because its just anything the robot can find in the moment it needs cooling. Even anything from a vending machine it can drink then. It will be kept in its own separate reservoir so it doesn't gum up the main distilled water cooling system. So the ice water/ice cubes/juice etc reservoir presses against the main distilled water cooling reservoir (containing only distilled water which won't gum up or corrode the main water cooling system). And by having the two bags pressed against eachother, the coldness of the one bag cools the distilled water cooling water bag, pulling heat out of that bag quickly. Once the two bags' temperatures reach equilibrium, the robot can then pee out the ice water cooling reservoir bag contents and go get another drink of ice water or cold whatever drink to rinse and repeat that process as needed. I don't anticipate it needing this extra cooling often, but in hot conditions or rigorous work that is quite physical or sports or dancing it would need this to add extra cooling to its existing cooling approaches. It would then "fuel up" on ice water in advance of rigorous physical activity to prevent overheating during said activity. Note: I originally planned to put the water cooling and ice cooling reservoirs in the chest of the robot but later realized I could instead put them in the belly of the robot more toward the front of the robot and this way the torso has much more room and these reservoirs won't take up so much room in the chest - which is much needed room. So then, when the robot needs ice cooling, it can drink a large volume of ice and cold water (or juice or w/e drink that's cold) and this will fill its ice reservoir bag which will then cause the belly to protrude like a pot belly. This is how humans work since when we eat a ton our belly sticks out. Same principle. This means we get bonus space available for this purpose outside the normal operating space of the robot's torso due to this natural protrusion factor. This bonus extra room in demand is a nice luxury since it means we don't have to accommodate cold water/ice/juice in the precious coveted space within the torso which gives us more room for other important electronics and stuff to fit in. Note: the reservoirs of the distilled water for the main water cooling system and the ice water reservoir for the ice cooling system both are best being as big as reasonably possible since the bigger the reservoir the more cooling you get and the longer it takes for those bags to heat up and start causing problems with heat. So then the bigger the reservoir the more sustained cooling we get. After both these reservoir's contents get heated up significantly, they are no longer effective at cooling the system and the robot would have to either sit down and rest and wait till these cool down naturally or would need to pee out the ice cooling reservoir bag warm/hot contents and go drink cold liquid and/or ice to fill the bag back up with something that will quickly cool the whole system down again and it can resume work right away this way with no downtime.
A colleague pointed out that the robot probably will need massive batteries. I agree with this in part, but with some caveats. Yes, to support the massive number of motors and the large bursts of energy required when most motors are firing all at once during rigorous athletic type activities, you would need massive batteries to supply all of this energy demand during peak periods. You also want the batteries to have a decent overall runtime duration. I intend for it to use fairly massive batteries for these reasons. However, there is a common misconception that the batteries must be so big that the robot is able to run all day on a single charge and that if it only can run for say an hour, that means it will only be capable of working 1 hour then charging and totally idol and not working for an hour or two and then get back to work again which would cap its productivity massively. People then conclude battery technology today rules out humanoids being particularly useful due to the lack of capacity. This is a completely solved problem and indicates people's lack of thinking this through thoroughly. The solution is simple: I don't have to worry much about large capacity for long duration of runtime since my intention is to have it hot swap battery packs frequently and always have 5-10 battery packs charging so that it always will be able to swap a new pack in that is fully charged. This way it can have 24/7 uptime while not having to carry a very large battery pack to have a long runtime. This is the same approach construction workers use with their cordless tools. They have a ton of packs charging at all times and use batteries till they get low and just swap a new fully charged one in as needed. They don't try to fit a entire days work into one giant battery. They have a ton of small batteries charging at all times instead and just hot swap full ones in for low ones. This should have been obvious to everyone as the perfect solution for humanoid robots too. Note: in my design, he will have a significant battery pack in the abdomen which never swaps out and tops itself up from the hot swappable battery backpacks as needed. This abdominal battery pack will enable it to swap in new hot swap battery backpacks since you need batteries running it while the hot swappable packs are being swapped. The hot swappable packs will be worn as a backpack just like a school bookbag. When available, the robot will optionally also be able to plug a AC power cord into the wall outlet to charge, although if it has multiple hot swappable batteries already charging by various available wall outlets then this would be redundant. It is a good tool though in general for some situations. Note: the backpack battery can be taken off and the robot will still have a very limited runtime just based on its abdominal battery pack. It uses this limited time to swap in a new hot swappable battery pack as the primary reason for the abdominal pack, however, another good reason to have a permanent abdominal battery pack is so that it can do demonstrations with no battery backpack on. A use case for this would be: lets say it wants to do a flip or cartwheel and the battery backpack's added weight would be a hindrance for such a maneuver. It could simply take the backpack off, do the flip or cartwheel, then after bowing for applause, it can put the backpack back on.
>>32044 Great ideas, Artbyrobot! I always enjoy reading your posts. BTW, here are some threads that related one way or another to your latest : (>>23, >>83, >>234, >>5080, >>11018) . Good luck with your project and cheers, Anon. :^)
Open file (5.45 KB 383x242 R.gif)
>>32048 I've been thinking about an energy-saving method, besides the power supply and propulsion system recently. With the way my desktop is working out, I was thinking of putting breaks in the joints. A power-on break uses power when the break is enabled, while a power-off break only uses power to disable the breaks. I was leaning towards the latter for a while, because it would mean more power is used while moving, but standing upright could be done indefinitely without using energy. I've been trying to come up with a magnetic flux-switching design for a break that would only use power when switching between off and on. A power-toggle break.
Open file (49.48 KB 378x710 SwitchedFlux.jpg)
>>32321 You may find switched flux motors to be interesting. https://www.sciencedirect.com/science/article/pii/S2090447922001022
>>32321 >>32322 I agree both are interesting. Something to look at and "ponder". Look at this video and see if you can tell what is going on. This appears to be a magnetic superconductor (B-field???) Leedskalnin_Effect_Demo https://www.youtube.com/watch?v=eWSAcMoxITw Why there's not a ton of speculation and people studying this non-stop, I have no idea. It's my understanding that a circuit like this can stay together indefinitely. Also if you keep the wire in and separate the plates the energy in will come out in a circuit connected to the wire. Not sure if it's the same amount but it is substantial. I think this is one of those things where scientist say,"well that's just so and so doing this and that(feeding you equations)..." while totally missing the point that this is a fairly huge abnormality and quite odd.
>>32323 That's just storing energy in a magnetic field. When you break the circuit, the field will reverse. This will cause the metal to de-magnetise and if a coil is there, some percent of the initial energy will be inducted. It's essentially the magnetic flux version of a capacitor. Transformers and inducters work on similar principles. You may also find electropermanent magnets interesting, same thing but with a permanent magnet to essentially create a switchable permenate magnet that won't induce as strong of a counter flux if the magnetic circuit is broken. https://en.m.wikipedia.org/wiki/Electropermanent_magnet
>>32324 >That's just storing energy in a magnetic field In my opinion this is much more interesting and strange than the standard reasoning you have just given. What you said is of course the correct opinion. The magnetic field is confined to the metal. It does not extend like a coil. To the best of my knowledge it does not attenuate over time or at the least any appreciable short time. Here's an article that explores this sort of weirdness RIGHT ANGLE CIRCUITRY - or - AC Electronics for Alien Minds (C)2000 William Beaty http://amasci.com/elect/mcoils.html Beaty has some super interesting articles.
>>32321 Very cool idea, Anon. MAGNETS.
Open file (837.41 KB 1080x871 IMG_2027.png)
So the pulleys were working fine except occasionally the thread would wedge between the plastic discs and the bearing causing the system to jam. My solution originally was to cut out finger nail clipping shaped pieces of thin clear plastic to glue onto the inner face of the discs that contain the bearing of the pulley which would act as standoffs preventing the pulley string from sliding between the bearing and the outer discs and jamming. It turned out this was borderline impossible for me as these tiny pieces of plastic were so tiny that even my precision tweezers were barely able to hold them and they would go flying in random directions and get lost - being clear and tiny they were near impossible to find as well. So this led me to taking a step back for a few weeks to work on other unrelated projects and take a break due to this impass/dead end. I came up with some ways to redo the pulleys but hated the idea of scrapping the ones I already made that needed improving. Well I have great news: I did find a way to salvage my existing pulleys that is reasonably doable and not nearly as hard though still tedious as can be. I am using Singer nylon clear monofilament thread and gluing down one end of that to the outer plastic disc of the pulley using superglue applied with the tip of a tiny sewing needle as my applicator and then letting that fully dry (can't use accelerant spray since it has to be very precisely applied and can't get on bearing but is being glued less than a millimeter away from bearing outer race). Then I lay the string along the crack formed between the bearing and the outer plastic disc which fills that crack and I apply glue here and there once every millimeter as I see need for it to secure the string along the entire crack while being careful not to get any on the metal bearing. I use an xacto knife blade to scrape any glue I get on the outer race of the bearing off and any I do get on the bearing I prevent from gluing the clear monofilament thread to the bearing by moving the bearing a couple turns while the glue is drying to keep it from gluing in place. I move the bearing using the tip of the xacto knife blade and I scrape any glue off as I see it on the shiny outer race of the bearing. I use about a 3" long piece of thread each time I do these gap filling passes and then trim off the excess from both sides once done. Attached is a photo with arrows indicating the gap filling clear nylon monofilament thread. I have since tested these pulleys that I fixed and no more jamming is occurring - it worked! Now I want to avoid doing this for every pulley and every crack on every pulley so for now I'm just doing it for known trouble cracks on certain pulleys that prove to jam up the system during testing. Once I can pass all testing without a jam for like 50 back and forth tests in a row, then I'll call this fix done.
Open file (1.28 MB 4032x3024 IMG_2026.jpeg)
Note: for future pulley making, to avoid this issue entirely, I plan to make the bearings outer race be grooved before I even make the pulley. This way the string passing over the outer race circumference of the pulley will not end up wedging between the outer disc and the pulley in the crack and jamming. The groove on the outer race of the pulley will keep the string passing along its outer race centralized in that grooved channel so it doesn't walk out and get jammed anywhere. To achieve adding a groove to the bearing outer race, I'm planning to lay the bearing flat on a piece of wax paper and then carefully applying epoxy to the crack between the paper and the pulley outer race filling that crack. Picture caulking a bathtub crack between bathtub and wall. Same concept. Then once that is done I flip the pulley and do the same for the other side. You then end up with a v grooved channel in the outer race of the pulley. The rest of the pulley assembly will continue as usual. Attached is a drawing of a pulley on a piece of wax paper with an epoxy bead applied filling the crack and forming one half of the intended v grooved channel on the outer race of the pulley.
Note: hitting that dead end with trying to fix the jamming issues with the pulleys and frustration with the pulley fix caused me to procrastinate on the robot build and temporarily call off my commitment to work on the robot every day even if just one small accomplishment per day. I still love that commitment and am now getting back to that now that I have come up with my solution and am moving forward again. It really is a great commitment to make sure I keep the project alive and actively in development. It is so easy to just not work on the robot once it is no longer part of my daily routine and the last thing I want is for months or years to slip by without me working on the robot much as has happened to me in the past so many times.
>>32559 >and the last thing I want is for months or years to slip by without me working on the robot much as has happened to me in the past so many times. I'm very proud of you, Anon. Not only am I very interested in seeing the progress of your project, I admire your fortitude. Every Anon here who's commited to achieving IRL results will have setbacks. It's the ones that simply refuse to be stopped by this that will see success in the end. [1] We're all rooting for you Anon! :^) Keep.moving.forward. --- 1. >"For though a righteous man may fall seven times, he still gets up" https://biblehub.com/proverbs/24-16.htm (BSB, 16a)
Open file (212.65 KB 674x298 Capstan.png)
Open file (3.27 MB 3112x2334 DifferentialPulley.jpg)
>>32559 Please understand that I fully support you. Pulley's do not work beyond a few at a time. I understand why you'd be enamored with the concept. Frictional losses are cumulative, and pulley's just aren't ideal for this application. Monofilament line is also not ideal do to its high elasticity and ease of permanent elongation from prolonged stress. Use a rope or braid in a capstan or chinese windlass/differential pulley if you want to use threads and pulley adjacent mechanisms. It will save you time and heartache. I'm personally developing a chinese windlass based actuator for MaidCom, though that is far from being ready to share. I hope you'll head my advice, but I understand if you feel too attached to pulley's.
>>32563 >capstan Wow, that is cool-looking, Kiwi. Looking forward to seeing what solution you finally arrive at. Cheers. :^)
>>32561 thanks and agree >>32563 the fact you thought the monifilament line is going to be handling load bearing duties as opposed to the clearly stated purpose of using it just to fill a small crack like using silicone on a bathtub crack makes me question how carefully you considered my post. I’ve consistently stated I’m using braided PE fishing line with very high test strength for my actuation cables whose tensile strength and elasticity are relevant. Also to anyone reading this thread, I want to strongly disagree with Kiwi's statement about pulleys not working beyond a few at a time. This is demonstrably false and very misleading IMO. You'll note from the smarter every day video on pulleys that Archimedes boasted he could pull a ship ashore solo if he used enough pulleys. This would involve WAY MORE than 3 pulleys. So to say you can only practically use a few is false. You'll also note 8 pulleys being used here in the same video: https://youtu.be/M2w3NZzPwOM?t=277 And the implied teaching is that this is far from the cap on how many you can use effectively. He never says "well this is about the max you can use". And in my robot I'm only using about 8 too just like he proves works great in the video as far as I can observe. So this is really not even up for debate IMO. Kiwi is just dead wrong it seems to me and the video proves it IMO. Now if the video is poorly presented and misleading and my conclusions based on it are all wrong, I am open to be proven wrong. Are there any sources to back up what Kiwi said or videos demonstrating what Kiwi said? I would need verification beyond hearsay at this point to be persuaded. ChatGPT also seemed to be on my side on this. I really don’t know any experts or people I can talk to on this, but Kiwi is the only person saying this of all the people that I’ve shown my project to. Also one more thing: you do realize I'm going for 32:1 or 64:1 downgearing ratio yes? So that in mind, when you say use windlass or use ball screw (old discussion in another thread), are you suggesting these methods are viable and more efficient than pulleys even at these high downgearing ratios? Because any method is lower in friction losses at lower downgearing ratios but my requirement is 32:1 or 64:1 downgearing at a minimum due to using low torque high speed bldc motors as my motor of choice. I understand some efficiency losses are involved, but that applies to using gears too. And hobby servos use 180:1 downgearing very commonly. They suffer some efficiency losses too but are considered good design. Chatgpt says: Hobby servos with gear ratios around 180:1 typically have efficiencies ranging from 70% to 85%. Pulley-Based Downgearing (32:1 with 9 Pulleys) Efficiency: A well-designed pulley system with ball bearings can achieve efficiencies around 80% to 90%. Chinese windlass efficiency: similar to the pulley system, generally in the range of 70% to 90%.
>>32563 I like that capstan. Have to think about incorporating that somehow.
>>32576 Could you break up the text for your posts? It'd help with parsing when trying to respond to your posts. I admit my error. I skimmed your previous posts and mislabeled the type of nylon line. Nylon still suffers from permanent deformation too easily for me. I recommend using some form of preloading to keep the system accurate. >Pulley's If you can make it work, then do it. Prove me wrong. I'll be waiting and hoping that you do. Until then, I stand by my assessment that they're not viable for wiafu. They are fantastic for large systems. I just don't see their use at our scale. >ChatGPT Not an authority on anything. Have confidence in yourself. You are a passionate engineer who should be comfortable stating facts and figures on their own merit. Or, site something that matters. That video was an excellent support of your claims. Actually, a personal favorite of mine.
Open file (1.93 MB 1722x3822 IMG_2159.jpeg)
Sorry for the long wait. Got busy with other stuff. Anyways, I completed the full pulley system and just got done testing it. It did not snag once anymore (rope binding between pulley and flanges) because each spot prone to that issue I fixed by putting some clear thin fishing line across that gap and gluing it down on either end. This closed every gap causing issues before and now everything seems to be going smoothly. I just did a big testing session on the pulley system and it was working perfectly (actuating it by hand for now). However, I got very aggressive and tried to attach a 10 lb dumbbell to one end and test that way. Pretty quickly the bottom-most string of the bottom-most pulley snapped. At first I thought the string itself broke in half but it's 20 lb test so a 10 lb dumbbell statically hanging should have been fine. Turned out it was my knot that came undone! I should have tied it a triple knot at least and put super glue onto it too in order to really secure it. Turns out that particular string attachment point I wanted to upgrade to 70 lb test anyways so it wasn't such a big deal. That will be my next step. Once I get that re-secured, I want to test it out with the 10 lb dumbbell and use a digital fish hanging scale to test the real world mechanical advantage. My intention is to find out how many pounds of pulling force I'm using to raise the 10lb dumbbell. It should be WAY less than 10lb obviously due to the mechanical advantage from all the pulleys. This will also tell us how much friction there is in the system which I'm sure is significant but I will know by this test EXACTLY how much is involved. The fact it is all working in general is very promising. The tests went very well just using one hand pulling down as the weight to be lifted and one hand doing the lifting on the other end. The hand I tried to pull down with was EASILY being lifted up. It did like 10-15 trials with no binding, tangles, or issues of any sort. It just WORKED. Too bad I didn't take a short video of the testing before it broke!
>>33778 Hello Artbyrobot, welcome back! It's been a while. >The fact it is all working in general is very promising. It really is. This robowaifu is going to be very, very cool when you finish her, Anon. Keep up the great work! Cheers. :^)
Open file (231.20 KB 1080x1035 IMG_2166.jpeg)
Open file (889.51 KB 899x1080 IMG_2164.png)
Open file (1.03 MB 1080x886 IMG_2165.png)
With my existing snatch block and block and tackle style pulley systems tested and working decently at 16:1 downgearing ratio which feels pretty complex and capped out by space constraints, I am now turning my attention back to some prior concepts for rotating in place pulleys I had planned years back and not revisited till now. The basic idea is you have a big pulley and a small pulley attached to eachother one on top of the other and so when the big one winds, the small one moves too and going from a small to a big to a small again (just like gears) gives you mechanical advantage. This is like gearless gears in a way works exact same way as gears except can't go continuously in one direction since its limited by amount of windings you can fit on it. Having a setup like this mounted direct to the motor is a no brainer I think. It will give me a 2:1 or 3:1 downgear straight off the batt and should be fairly easy to make using a 1mm OD x 20mm length stainless steel dowel pin mounted to side of motor sewn into place tightly and then using a little copper tubing for a electrical connector as the rotating sleeve and onto this sleeve gluing down the flanges using the same plastic as what I used for the pulleys (clear sushi and produce containers plastic). That pre-downgearing at the location of the motor will bring our Archimedes pulley system from 16:1 down to 32:1 and possibly 48:1 roughly if we can get between 2:1 and 3:1 downgearing ratio on the motor. I also am considering just doing ONLY these types of rotating in place pulleys instead of the Archimedes pulleys style of downgearing. It might be more space efficient perhaps. I don't know which will be more robust and which will be a maintenance nightmare. I just dont know which is easiest to work with. Also which is easier to make. I have to make both styles and compare. I think the turn in place style may be more space efficient by a long shot but not 100% sure on this. When I do the turn in place style mounted flat onto the robot's bones, I plan to use a flat head thumb tack for this as the bone mounted base and then have the rotating pulleys turning in place over this. The flat head thumb tack can be sewn tightly onto the bone sleeve to secure it in place well. I'm not sure how well this approach will scale to higher forces of larger muscles though. Perhaps it will scale fine if I just make the pulleys bigger. So much to experiment with...
>>33811 Thanks, Anon! Again, looking forward to your results with Eve. Cheers. :^)
I finished fixing the fishing line on the bottom-most pulley with 5 knots this time to make sure it doesn't untie. I hung the 10lb dumbbell from the pulley system and to my horror, two fishing line points snapped almost immediately in two new spots. These fishing lines were rated 20lb test and 130lb test. How is a 10lb dumbbell snapping them when hung gently? I don't get this AT ALL. I am wondering if it is a quality control issue with the fishing line or false advertising or just a bad manufacturer or what. Any thoughts? This is VERY frustrating and baffling to me. They did not untie this time they literally snapped in half. This is truly baffling. Update: some more clues: turns out both snap points were within a millimeter from where the fishing line entered into the bone fabric sleeve where it was stitched over and over to tie it well into the sleeve. Perhaps this area just sort of was weakened by the sleeve and tugging at that spot and abrasion somehow? I am thinking I should tie a small metal ring into the bone fabric sleeve and then tie the fishing line onto that ring with a figure eight knot so that the fishing line doesn't chafe on the nylon fabric as much and has that little separation point tying off on the smooth metal. Hopefully that will solve it.
>>33859 Sorry to hear about this minor setback, Artbyrobot. >Any thoughts? Perhaps you're correct about the sleeves somehow unduly abrading the line? Maybe you could slip some Teflon-type sleeves on the entry/exit areas of the sleeves where the line come in intense contact? Also, there are a number of advanced, technical fishing lines that various robotics projects have used, apparently to good effect. These basically all are 'ultra-high molecular weight' type lines. [1] Good luck solving this issue, and may you solve all of them, Anon! Cheers. :^) --- 1. https://en.m.wikipedia.org/wiki/Ultra-high-molecular-weight_polyethylene
>>33859 Knots reduce the strength of strings. Same is true from the stress imposed by every loop of pulley. You don't have to worry much about the pulleys assuming they are smooth and spin freely. You need to seriously overspec your line and using braided string will help. As a rule of thumb, assume every knot halves the carrying capacity of the system. As an engineer, you should expect 80% of spec. So, you'd have 80% of 130 = 104 then divide that in half 5 times for each knot, you'd get around 3 pounds of expected carrying capacity. Of course, this is all based on worst case scenarios but, we must design for the worst and hope for the best. This link may prove help you, it has helped me. https://www.theknotsmanual.com/rope/rope-strength/ Further more, try to reduce all points of contact with the string. It would be ideal for the strings to only ever touch pulleys and mating surfaces.
>>33864 If I remember correctly, loads for safety line, like for climbing is 5 times breaking strength.
thanks guys great suggestions. Ok so my solution to the issue I had of fishing line breaking when tested by hanging a 10lb dumbbell is finally here folks. The solution is to sew a fishing hook's eye into the bone sleeve snugly with upholstery thread as a anchor point. Then I will draw my braided PE fishing line through this eye and back down. Instead of tying it off with a fancy knot which acts as a weak point or concentrated stress point, I will use a fishing crimp sleeve to crimp the rope off on itself. Similar to crimping two pieces of wire to eachother with a electrical crimp tube. Supposedly fishing crimp sleeves are used to avoid knot tying and offer even more integrity than a knot can while maintaining fishing line integrity more than a knot can. No weakness is introduced to the line like knots do. A side benefit is this crimp also protects the line from abrasion and acts as a physical standoff so the line isn't rubbing the bone sleeve as much which can cause micro abrasions and weaken it over time. I bought #2 and #3 fishing crimp sleeves which were around $6/100pcs on amazon.
>>33778 Do people ever ask you what you're making when you buy supplies? What do you tell them?
>>33890 Sounds good, Artbyrobot. Please keep us all up to date with the results of this experiment! Cheers. :^)
>>33891 nope never.
By popular demand, here is some math I did regarding the motor and pulleys for the finger actuation. 64:1 downgear ratio 24 inches total draw onto motor shaft 24 / 64 = 0.37" draw at finger joint 2430 motor 5900kv at 12v RPM = kV * V RPM = 5900 * 12 RPM = 69600 69600 / 60 = 1160 revs/second 1160/2 = 580 revs / half second 580/2 = 290 revs / quarter second if motor reels around 1cm / rev then in quarter second it reels 290cm... and 30cm = 1 foot so 290/30 = 9.6ft/quarter second maybe it only reels 3/4 of that? even so... around 9.5ft/quarter second - and quarter second is the speed of a human finger moving... we only want to reel 24 inches... and it is reeling 9.5ft so if it only reeled 24 inches that would be human speed... so if it only reeled 60cm that would be human speed... but it reels 290cm... around 4.8x human speed! now for strength at this 64:1... an online google search said a 2430 motor can pull 60 g cm... 120 g at 1/2cm 240g at 1/4cm maybe we are around between 1/4cm and 1/2 cm away from shaft of motor on average... so 190g at that distance... 190g is 0.42lb... 0.42 lb * 64 = 27lb so a single finger joint can do 27 lb dumbell curls ALONE - well wait since it's lifting a lever at the joint, it is much lower than this maybe 1/5 of this so 5.4lb dumbel curl is more realistic... now this is all for torque at efficient natural movement speed... what about stall torque - IE how much can it just HOLD in place like rock climbing dead weight it can't move but can hold steady? it's stall torque is around 280 g.cm compare that to its normal torque of 60 g.cm so 4x... so it can HOLD steady around 20lb! that is about what my finger can hold steady for a single finger tip!
>>33934 Thanks for the detailed information, Artbyrobot. That's a lot of details! :^) >around 4.8x human speed! High speed, low drag. :D Looking forward to your current results, Anon. Good work! Cheers. :^)
Open file (20.47 KB 114x120 IMG_2182.jpeg)
Open file (22.26 KB 116x120 IMG_2181.jpeg)
Open file (27.58 KB 120x106 IMG_2180.jpeg)
I came up with a design for a way to do all my downgearing 64:1 by way of pulleys that is so downscaled that it can fit onto the top of the 2430 motor and achieve the full 64:1 downgearing for BOTH directions of travel. So the 64:1 downgearing system will start with two fishing lines (0.08mm in diameter 6lb test braided PE fishing line) wrapped onto the output shaft of the BLDC motor in reverse directions - one clockwise and the other counter clockwise. These strings will then travel to each of 6 downgearing stations that will each double the previous torque achieved. So downgearing station 1 will double both of the string's torque and downgearing station #2 will double that bringing the total torque to 4:1 torque. Station 3 - 8:1 torque, station 4 - 16:1 torque, station 5 32:1 torque, station 6 64:1 torque. Each station is made up of a stainless steel thumb tack with a #3 fishing crimp sleeve placed over the tack shaft forming a plain bearing pulley system. Little plastic discs will separate the various sections of this pulley system up. The discs plastic will be strawberry containers clear plastic from the grocery store (same as they use for lots of fruits, cakes, deserts, etc, the clear thin flexible plastic). The 2x torque is achieved by the string wrapping a 2x diameter pulley and a 1x diameter pulley. So every other section of the downgearing station will be 2x in diameter for this to work. Each downgearing station will be clockwise or counter clockwise rotating depending on which string it is downgearing. As the torque increases, the total wraps happening at each station decrease because the string travel is decreasing in distance by 1/2 the previous station's distance of string travel. At each station, as this phenomena occurs, a stronger fishing line can be used that is larger in diameter as needed. So only the first couple stations will use that 6lb fishing line but later stations will swap to stronger stuff since higher torques are getting involved at that point. The thumb tacks I considered welding together or brazing together. I considered Oxy-Acetylene micro torch welding, large soldering iron brazing, micro tig welding, pulse welding with a jewelry welder, spot welding, etc. But all of these approaches I am not that experienced with. I think I'll try brazing first and if I struggle with that I'll move to fiberglass and superglue where I have the most experience. My intention is to join each downgearing station thumb tack into its neighbor at the base and get them all to form a flat plane for stability and precise positioning. I intend to prepare the stations all together off the motor. Then when it is one solid structure with all of them glued to their neighbor and all pulley plastic discs added, at that point I can attach the whole assembly onto the 2430 BLDC motor top and suture it into place there. The teflon guidance hose attachment guide structure will also have to be part of this assembly for easy and secure attachment of the teflon hoses at the end.
>>33947 >I came up with a design for a way to do all my downgearing 64:1 by way of pulleys that is so downscaled that it can fit onto the top of the 2430 motor and achieve the full 64:1 downgearing for BOTH directions of trave WOW! This sounds amazing, Artbyrobot. I wish you good success with this design. Really looking forward to seeing what you manage with this approach, Anon. Cheers. :^)
>>33947 Very nice!
>>33890 >>33934 >>33947 Glad to see you gaining knowledge. You're on the right track and I believe you'll achieve great things. As for your math, what is the circumference of your main shaft? What about your pulley's? Theses do matter for calculating your speed of spring take-up. Multiplying Kv by V to attain output speed is generally good enough, do remember this is unloaded speed. If you're using a sensored BLDC motor, especially if you're using Field Oriented Control (FOC), you can get that if your load is low. Since you're using a 64:1 mechanism, you should achieve close to your calculated RPM, but never quite there. The BLDC still has to accelerate to your desired velocity, this should be in a fraction of a second, it's worth having it in the back of your mind. Especially when switching directions. As for torgue, this is surprisingly complex. To keep things simple, you'll likely get close to Nm=(8.3*A)/kV. Your high velocity constant of 5900Kv translates to a lower torque constant. Assuming 2A, you'd see almost .0028Nm, or 28grams per cm. Pull force on the string is then N=Nm/radius in meters. As for making pulley's out of thumbtacks and crimps, that's clever. The plastic your strawberry's came in is PP (polypropylene) which is low friction. You should still use some kind of grease, preferably with graphite to keep things smooth over time. Your design is similar to this video https://www.youtube.com/watch?v=z11xJi-MvYI Hope this helps, I look forward to seeing how your design works IRL.
Open file (236.73 KB 1600x1093 IMG_2186.jpeg)
TheRobotStudio on YouTube is doing an open source robot called "Hope-Light" and inviting his viewers to follow along with his progress . I have decided to follow along, although I will be modifying his designs as I go to customize it more to my liking. He expressed he wants this to be a open source community to advance humanoid robotics development in the DIY space and usher in the wider adoption of humanoid robots in more homes across the world. He's excited for what this can mean for global productivity and quality of life improvements it can bring if executed well. I like this vision. My decision to follow along with his project is to pick up a extra head of steam in my own humanoid robot building projects by utilizing his experience and formal education in robotics engineering as a legit decorated world class humanoid roboticist. A world leader in the field. By following his open source project loosely, I can get a breath of fresh air by skipping past the bang my head against the wall dead-ends and regular difficult hurdles and just get results. Sort of like fast food drive thru. It will be a relief for me. And confidence booster. To see something really happen at a faster pace for a change. Now none of this is to say I'm abandoning my existing projects. They will all go on as planned without interruption. This will be a parallel journey I will share. I will certainly learn a ton and can apply what I learn to my other projects. I will have this Hope - Light robot adaptation be named Dinah. I'll use Eve's base mesh for the external appearance. The two females can look similar in build but have different faces. This robot will use to some extent TheRobotStudio's design philosophy and approach for the Hope-Light project. This means it WILL use metal geared brushed DC servos and it WILL use non-human-like bone structure, but I will still give it human-like realistic silicone skin and it will use the exterior exoskeleton shell of the Eve robot I 3d modeled already. One downside to this Hope-Light parallel implementation is that because it uses metal gearing it will be loud in its operation. So it will never be able to pass for human in public. That's okay though. My other designs are reaching for that aim and my other designs are still the intention for Adam, Eve, and Abel. So that vision remains alive. And will continue. But this noisy robot will still be a great learning experience and capable of doing useful work including helping me build my other robots, chores, manufacturing products, cooking, etc. It will probably do most of the things the Adam, Eve, and Abel robot can do but not be as strong, fast, and articulated. So it will probably not play sports well or do rock climbing or various other serious physical strenuous types of work. But the long list of things it should be able to do is still enough for it to be awesome. A great thing is that it won't be so experimental and outside the box like my previous solo approaches. This one will be designed to a small degree by a real professional so it will happen way faster and more surely than mine. Although I am finding I am changing his design so much it's not really his design at all anymore but my own. However, I still plan to retain a significant number of strategic decisions, placements, and organization following his lead. My other designs are more of a pipe dream shooting for the moon. Going more similar to this open source one designed by a real pro is more of a "sure thing". Not that I don't believe I can achieve my more ambitious designs, but just that they are admittedly a taller order and more crossing fingers about them is all. I really think building a top tier legit walking and talking full humanoid is going to legitimize my journey more in my own eyes and give me a better resume to bring MORE hope toward my own robot builds. Just seems like doing this is a no brainer. I've attached a early design progress image from TheRobotStudio who is currently designing Hope-Lite in Solidworks. You'll note he fused the distal knuckle of 4 fingers so they are permanently partly bent. This was a decision to cut down on complexity but in my preference, I'd rather have that functionality. You'll also note that it cannot pronate or supinate the wrist. That takes away a TON of functionality which is not my preference. So my robot will add this function back. That said, as I was studying how to add pronation and supination without a ulna and radius bone, I stumbled across the simple and effective design of posable love dolls' skeletons. I realized they have pronation and supination in their stock skeletons, so I decided I will use that kind of skeleton for this project. They are simple, very strong, welded steel construction with heavy duty hinge systems. To be posable, the hinges are quite stiff, so I will need to loosen all hinges to reduce friction. They are a hollow lightweight tubing style. Actually not that heavy.
Open file (6.71 MB 3312x5616 IMG_2187.jpeg)
So today I went ahead and extracted this metal skeleton from a male love doll I had bought some months back to use as a base form from which to sculpt the appearance of another robot. I bought it mainly wanting the already decent human appearance it offers in the TPE body and face that can act as a starting point for sculpting a robot. This is better than having to begin sculpting from scratch in clay and making a mold or w/e. Just a shortcut for me. I bought a decent used male love doll for a few hundred dollars which was a bargain to say the least. The shipping alone had to be close to $200+ so it was priced WAY below the cost of the raw materials if I were to try to buy 50lb of TPE rubber. I intended to melt down the massive amount of TPE rubber once done using it to assist in the sculpt of another robot and use that melted down rubber to create the skin for a robot. So those ideas were I had planned for this doll. However, now that I have decided to use the skeleton for a robot build - now I'm REALLY maximizing that little investment! So after 4-5 hours of carefully removing the skin from the frame, I have it all off. I made a few tears here and there in the doll from rough handling during the skinning process and the lack of experience at this, but it went well overall. It was a very physically demanding job to separate the skin from the frame since you had to pry at it, cut it, and peel it and the whole time it fights you wanting to snap back to its original shape. I am quite sore but glad I got it done in a single day. Attached is a photo of the skeleton I just extracted and will be modding and using for Dinah Now, having gotten the skeleton out and analyzed it carefully, I noticed it does not have the ability to shrug, so I'll have to add a hinge on both sides to enable that movement. Also, its bar where the tibia and fibia would be is not proportional in length to the bar that acts as the femur. I can see that they made the doll taller by just adding length to the tibia/fibia bar rather than proportionally adding height throughout the robot. So its proportions are off due to their laziness or oversight. In any case, I have to modify ALL the proportions some I think to match the proportions of my Eve base mesh sculpt. The neck is also quite hard to bend so I might have to add a couple hinges to it. All the nuts for every hinge on it are welded into place to prevent them backing out so I will have to grind off all these welds so I can loosen the nuts to disable posing and instead have all joints freely moving to reduce friction. I will have to add proper fingers and a palm. I will 3d print these bones for the fingers. TheRobotStudio is using Feetech SC0009 servos for the fingers. I'm planning to substitute in three N20 66rpm motors in place of each Feettech SC0009 servo. By combining three of these N20 motors, I am able to surpass the total torque of the SC0009 servo but after factoring in the size of our respective output winches, mine will be about 13% slower than his. This is fine by me because his robot hand designs are always extremely fast in finger speed and I can get by 13% slower than this. The purpose of swapping in N20 66rpm motors for the Feetech SC0009 motors is to cut costs and I just have a ton of them already and have been itching to use them. The Feetech SC0009 servo is around $11 and my N20 66rpm motors are only around $0.80 so 3 of them is $2.40. So that's $8.60 saved ever time I do this part alternative strategy. Well the savings is a bit less since I then have to supply my own motor controller H-bridge chip and potentiometer to read joint angle. So maybe only $8 saved. However, from what I gather, the Feetech SC0009 requires a serial adapter board to run it and doesn't use PWM but uses serial. I do NOT like this AT ALL in terms of my preferences and the adapter boards were $13 each and only serve 4 servos. That will add up quickly. So I'm actually saving that cost too. I prefer my microcontrollers to pwm directly to the h-bridge with no middle man software whatsoever to maximize my control. TheRobotStudio is using 3 different sizes of Feetech servos in his approach. You can see the wrist servo is much bigger in his CAD model. I am operating under the assumption I can cram TONS of these little N20 66rpm motors and use more than one of them per joint. So I can use as many as I need to get to the torque I require. I will use L298N motor driver h-bridge chips with these N20 66rpm motors to drive them. This chip can safely power 2 N20 motors per channel and has two channels. It's VERY cheap maybe like $0.15 per chip I think - don't remember. I'll use Arduino mega to send out the pwm. I'll use 10k ohm 3 pin wheeled potentiometers to read the joint angles and these will be coupled to the joints by fishing line which will translate the joint angles over to the potentiometers whose values will be read in by the Arduino Megas. So a lot of my own designs for control and sensory input I'm sticking with for this project but using various elements of Hope-Light for a hybrid approach and swapping in different actuators whenever I feel inclined. >>33955 The cm of the main shaft was included in the calculation already in the calculation post above. The cm of the pulleys doesn't matter in itself but what actually matters is the size difference between the thicker pulley and thinner pulley being 2x in diameter so each pulley acts as a 2x from the previous one. So only the relative size matters between one pulley and the next - just like how it is for gears.
Open file (3.87 MB 5766x6250 IMG_2190.jpeg)
I just came up with a cool alternative way to downgear a 2430 BLDC motor that might work. Attached is a illustration of the cheap downgearing idea: So basically, I figured what if I could remove the N20 motor from its gearbox/"gear set" by cutting it free or w/e. But I keep its center axle in place cutting away only everything else. You'd then presumably have a metal shaft as a entrance to the gearbox and a metal shaft exiting the top of the gearbox. I then turn that metal input shaft and output shaft into pulleys. I feed my 2430 motor output shaft pulley/winch into the input shaft of each of 4 N20 motor gearboxes, evenly distributing the load. Each gearbox downgears my 2430 motor 150:1. Each gearbox chatgpt said could handle about 5-6lb load but this can't be sudden or fast direction change this is really pushing it. But it seems 4 gearboxes should handle most of what we'd want from a 2430 motor. And the fact we can fit them all within the height of the motor output shaft default length and within the width of the 2430 motor diameter for the most part seems it would be a pretty significant downgearing for very low space taken as the cost. You could even locate a few more gearboxes off the motor anywhere and have those fed further distributing to them the load if only 4 gearboxes was not enough to handle expected forces. The cool thing is supposing we did this, it would cost us four N20 motors which is $0.80x4 = $3.20. That is VERY cheap for a gearbox as I read that a planetary gearbox for it would be like $25-30! And the planetary gearbox would take up WAY WAY WAY WAY more space which is highly coveted in our application - space we can't afford to spare. And the great thing is these little gearboxes you can fit ANYWHERE into a nook or cranny since they are so tiny... and you can use as many as you want to get up to the total forces you need them to handle as a collective. Seems like this could be a cool technique. I want to give it a go. Any thoughts? Note: this would be something I'd try on the Dinah robot where I'm using metal gears despite the noise these create since its a lower budget simpler robot I'm doing just to get something done faster for a change. My Adam, Eve, and Abel robots will be going pulleys to downgear to make them very quiet in operation as has been the plan forever.
Good luck, Artbyrobot. Looking forward to seeing your accomplishments with both the old & the new project plans. Cheers, Anon. :^)
Open file (166.00 KB 568x600 IMG_2191.jpeg)
The Dinah robot is coming along well. I modeled the full steel skeleton in CAD to match the dimensions of the Dinah base mesh and created a human bones variation as well to compare that to the steel simplified skeleton and make sure all the joint pivots matched the locations of the human skeleton joints pivot points. With this CAD, I will be able to modify the proportions of the steel skeleton I have on hand. I also added several key additional joints using reference photos of a skeleton I found online. For example I now have 2 pivot points for the knee joint instead of one which gives more clearance when knee bends back. I also gave a few more degrees of freedom to the neck and shoulder area. Note also that I am well on my way to finishing up printing ABS solid infill fingers and wrist bones which I will retrofit onto the steel skeleton so that I can have full 27 degrees of freedom robot hands and wrists to match perfectly the dexterity of the human hand, which is a must. I have decided that once I finish the arm and head, I will not go on to complete the building of the rest of the robot's body but instead will switch my focus to the AI entirely from there forward. I will code the AI to cause that arm and head to build the rest of its own body.
Open file (56.41 KB 750x834 fake niggas.jfif)
>>34016 > I will code the AI to cause that arm and head to build the rest of its own body. This is a pipe dream, and completely unfeasible. If you go down developmental road your project will never progress behind a tote of printed parts, a used masturbation skeleton and a half-baked, incomplete attempt at code. Be more pragmatic. There is zero (0) chance of you being able to get a simple robotic arm and hand to assemble anything close to as complex as itself. Think about the wire routing, the fasteners hell, think about literally any point during the assembly of the arm in which you were required to use both of your hands simultaneously. Assemble the robot seeing as how you've already made progress on that front. That's the easy part. After that, get to work on the software side. Even if you only have a fancy animatronic, any effort made after that will have a ready test platform. Set smaller goals for yourself and you'll make progress.
I have absolutely zero use for or interest in a robot that cannot build the rest of its own body with one arm/hand and a head. Therefore stopping all further building after the bare minimum hardware of one arm and one head are completed is the only reasonable path. It saves the time of me doing future building myself which the robot could’ve done for me. It also acts as the final conclusion of the project accepting total failure if my AI does not bring about the building of the Robó body using just that one arm. I would accept defeat at that point. There would be no purpose in building the rest of the body, shy of an AI that can do that. This is where the rubber meets the road. If I fail the AI, then I had no business building a robot to begin with because the only robot I would ever be interested in is a robot sophisticated enough to build its own body with a single arm and head. For times where it needs that second hand to be able to do something, I obtained the necessary extra robotic helping hand simple pincher toy to fill in the gaps where this fully dexterous human hand needs a little bit of help. Also, it can use the usual vise or electronics helping hands for additional options for it to hold things while it works on them. If I had those options, I could build the robot one handed.
Open file (159.13 KB 1280x720 kill it.jpg)
>>34019 You're setting yourself up for failure. This isn't "where the rubber meets the road" this is "where the project stops making progress". I get you have ambitions, but you're jumping ahead too far; no proof of concept, no prototype hardware or software, no practical understanding of the problem. Even if you were to go down this path with all of your effort, you would still need to take smaller steps that you seem to be unwilling to take. For instance: a small goal of getting your robot arm to assemble a simple structure. Say, screwing six fasteners of various size in to a block, and routing a wire into a channel of extruded aluminum; things that will be analogous to assembly of your completed design. Make that happen and sure, you're on the road towards what you want to do. But you're either grossly underestimating the difficulty of that problem or willingly abandoning your project with the inbuilt excuse of "I'm working on the AI, and until that's perfect this project is meaningless." Also this doesn't save you any assembly time. Printing and assembling the parts will take a small fraction of the time that programming and troubleshooting even the above example experiment would take. You're shooting yourself in both feet.
Open file (3.19 MB 2652x3612 IMG_2193.jpeg)
I managed to get Dinah's hand bones printed out in ABS (100% infill) on my Anet A8 3d printer the past couple days. I also cleaned up the prints, removed the supports, and sanded down high points. They are ready for attaching them together with cloth tape which will act as artificial ligaments. You'll note I fused the ulna and radius bones together to use as a rotational joint for the wrist to function like a human wrist. The actual pronation and supination of the forearm though will happen by way of the steel skeleton having a rotating pivot point unlike the human body where the radius rotates and twists over the ulna in a criss cross. Note: in this photo the middle finger is missing the distal tip which I was reprinting as the time of this photo.
Open file (8.32 KB 400x286 3dphinge_detail.jpg)
>>34016 >That skeleton and metal frame Been there, tried to do that, one of the worst mistakes in my life. Your steel bones were never meant for a robot. They will never be meant for a robot. I say this as someone who truly wants you to succeed, this is a dead end. I failed already, you don't have to repeat my mistakes. You may have many arguments on how you can still move a high mass frame. You may have arguments on how its movements are good for a robot actually. They won't hold up to reality. You're free to ignore my warning. I'll just be sad to see you wasting time. >Using AI to have the machine complete itself after just an arm and a head. I'm unsure on how you could possibly think this makes sense in anyway. The level of dexterity and complexity needed is beyond what anyone on earth has ever built. I say this as someone who works with arms in manufacturing, they cannot build themselves. It requires many specialized machines working together in perfect sync with human help. There is no AI that can out think a man, and no man can build an arm that can build a humanoid on its own. >>34019 >If robot cannot build itself; Then no interest You're either operating under a tremendous burden of hubris or delusion. Please, scale back your your project. You could still build something that benefits humanity. It's depressing to see a bright mind waste itself on a project with a scope that eclipses all reason and sanity. >>34020 I dislike their tone but, they are correct. >>34021 >ABS >Cloth tape ligaments That's going to fall apart. Cloth tape won't securely adhere to ABS long term. Using fasteners such as screws would keep things together long term. It's plastic, you just need to place the right sized hole and the screws will self tap. It's an easy fix. Frankly, your hand should be one peice with flat sections for living joints. That would be far more functional, easier, and last a heck of a lot longer. Please, take a step back and think of how to kit is simple smartly. https://hackaday.com/2023/05/01/hinges-live-inside-3d-prints/
Just weighed the steel skeleton - it’s 8lb 11oz
Open file (730.60 KB 1200x848 sukabu.jpg)
>>34022 >I dislike their tone but, they are correct. That's me. I'd like to clarify, if there's any ambiguity, that I am not wishing this project or its designer any ill will. I'd like to see everyone on this board accomplish what they set out to do. I mentioned it before in my embassy post, but I truly believe that great strides in the world of humanoid and companion robotics can and will be made by very talented, passionate and bright people like those found here. I'm not trying to be negative, I am trying to clearly express that this ultimatum that the designer has set for himself is a mistake. Progress is seldom made in tremendous leaps, and things like this require iteration. Look at the minds behind some of the most impressive robots out there and examine their design paths. Skipping directly from "first iteration robotic arm and head" directly to "self-assembling sentient automaton" is entirely unfeasible and tantamount to abandoning the project entirely. OP, look to your peers on this board alone. We've seen many projects fall by the wayside after more progress than has been made on this one as a consequence of much more benign factors. You should do everything you can to avoid sharing their fate. If I were to offer more direct advice, it would be to set a flowchart of goals for yourself: head and arm -> object tracking with head -> reaching for tracked object with arm -> simple manipulation of object with arm -> construction/refinement of second arm and existing arm -> integration to torso and beginning form factor -> simple integrated AI system (speech recognition, LLM support, facial recognition etc.) -> enhanced object tracking and utility capabilities -> refine form factor -> locomotion (first iteration: wheeled dolly with skirt or similar)->.... so on and so forth. The fact that you've made this much progress shows that you have the capability to make something remarkable. It'd be a tremendous disappointment to yourself and this community to see your efforts come to nothing. Honestly, I want to see you succeed.
Open file (2.32 MB 4032x3024 IMG_2203.jpeg)
Open file (2.43 MB 4032x3024 IMG_2205.jpeg)
Open file (2.60 MB 4032x3024 IMG_2204.jpeg)
Open file (2.28 MB 4032x3024 IMG_2207.jpeg)
Open file (1.72 MB 4032x3024 IMG_2208.jpeg)
In these photos you can see the progression of going from the stock wrist to an axial rotating wrist assembly acting as a plain bearing. Pardon the Orgrimmar welding its a cheapo welder. The process involved cutting the bolt head off then grinding smooth the threads and then sliding on a stack of washers and welding the last couple washers into a mushroom head end stop then welding the other washers to eachother and these ones are to spin freely. They will do the pronationa and supination. This replaces the need for a ulna and radius for that purpose, simplifying the skeleton some. The metal outcroppings I left on the washers were meant to jut out significantly to give the fiberglass something to bite onto well for a dependable attachment. Note: The stock skeleton does rotate already at a spot just near the elbow but that rotation is stiff and requires significant force to get it to move and loosening it is something I don't know how to do. I don't even know how it works at all. Advice on that for future reference would be helpful. Note: There is too much clearance on the stack of washers so they can slide distally or proximally a good 8mm which is not okay - too much play. I need to fill that gap and lube it all with white lithium grease. Note: I'm planning to probably just go fiberglass wraps over and over onto the stack of washers to grip it tightly and build outward from it and then go out and around the welded mushroom cap and then wrap onto the ABS wrist ulna/radius fused section that the little wrist bones will attach and rotate/roll on. Also note that I have reconsidered adding a dual hinge to the elbow joint and lean now toward just leaving it stock. I think the double hinge would add complication to the bicep attachment and cause some issues I'd rather avoid. A single hinge is easier to deal with IMO. And leaving it as stock as possible is a time saver. Of course, when I say leave it stock, that just refers to the overall design of the joint. I still have to loosen the joints to allow for free rotation.
Open file (1.45 MB 3296x2560 IMG_2220.jpeg)
Open file (1.84 MB 3368x2752 IMG_2221.jpeg)
Open file (1.70 MB 2538x2322 IMG_2222.jpeg)
So I finally got the wrist done. And aside from grinding off welds on bolts and backing off the bolts to allow for free movement at joints, I'm mostly going to try to keep this skeleton stock for the most part. So I may be attaching the hand and going immediately into electronics rather than fiddling with the skeleton adding more range of motion here and there. I can always add that later anyways. And in fact the poseable joints that are fairly stiff I'm finding is actually pretty convenient while working on it so I may only free joints on an as needed basis for testing electronic actuation of that joint. Until then I'll leave them alone. Also note: I was planning to have the wrist rotate axially around the location of the wrist for the pronation and supination. However, I realized this will not look right since you can visibly see the forearms move and the muscles there moving when you pronate and supinate your arm. So I have to have the pronation and supination be where the skeleton was originally doing this near the elbow. This will allow for much more natural looking pronation and supination. So the wrist location will not rotate AT ALL after all. This made it all the easier to make the ulna and radius distal wrist joint where the little wrist bones and hand will attach to and rotate on. I sculpted it all in fiberglass and super glue with some nails and some ABS plastic pieces and epoxy to build up the shape. I used my ABS 3d print of this part as reference only. This thing needed to be very strong as it's likely going to the point of failure as the rest of the arm is steel. So I wanted to make sure it was maximally solid and didn't fully trust just going with a 3d print there.
I predict this is all going to be amazing in the end, Artbyrobot. KEEP.MOVING.FORWARD. Cheers, Anon. :^)
Open file (1.17 MB 2160x2292 IMG_2236.jpeg)
Open file (517.38 KB 1428x1356 IMG_2237.jpeg)
Open file (971.98 KB 1560x1716 IMG_2238.jpeg)
I'm currently working to sew all the finger and wrist bones together for the Dinah robot and mount them to the arm. I wanted to show how I'm doing this process. First, I tape the bone with adhesive transfer tape 3M 300 LSE. Note that I leave space on either end of the bone to allow some free fabric which is necessary to allow for elasticity as the bones need to rotate after all. Have to have enough free fabric to stretch as the joint rotates, allowing the rotation. But not so much free fabric that the joint is loose either. Has to be just right and snug. Next I wrap the compression workout shirt fabric onto the tape and cut it to size. The sewing is done with nylon upholstery thread and a curved suturing needle and a surgical pliers using a suturing technique.
Open file (3.50 MB 5712x4284 IMG_2247.jpeg)
Okay, so I finally got the Dinah robot hand sewn in and it is looking pretty good. The fingers could use some tweaking but overall I'm quite happy with how it came out. It's solid and fully articulated. Now that out of the way, I want to announce I'm officially rerouting the Dinah project as far as its current goals and here's why: so basically I was thinking it would be nice to just crank out a working robot using some shortcuts and just do something quick and dirty as a learning experience side quest to get something going. It seemed reasonable at the time. Plus I could pace myself to match the build pace of a fellow roboticist and loosely follow his project's designs. But some things I missed in this decision: #1) I'd be lowering my commitment to excellent quality with no shortcuts - ignoring the adage "do it right the first time" #2) by cutting down on workmanship maxing, I'd be inviting harsh criticism on the new lowered bar of build quality which is the last thing I need when already inviting heavy criticism for a extremely ambitious set of goals to begin with #3) I'd be going against my outspoken commitment to campaign against loud metal gear noise based robots that are completely impractical for home use due to sounding like a construction site #4) it would take away from the focus on my "real" robot projects by creating a "ghetto" side quest robot that could have just been skipped altogether. #5) this would in turn delay me truly solving downgearing by pulleys and actuating the robot arm silently once and for all, proving it can be done and proving that achieving a fully human level DOF human body while maintaining a human form factor and making all of this silent can and should be done for humanoids. So is Dinah robot just trash now? No. I still plan to have this project be done, but only while using the best methods I have including silent BLDC motors with silent pulley based downgearing.
Open file (517.46 KB 1128x1044 IMG_2249.jpeg)
Open file (1.19 MB 1986x1626 IMG_2248.jpeg)
Here is a progress update on the silent pulley downgearing system I came up with using thumb tacks and a #2 fishing crimp sleeve and little plastic discs. It is some tiny fine precision necessary work but I'm getting it done and things seem to be looking pretty good so far. For now, I ended up just using 401 glue to glue the thumb tacks down onto post it note paper. I then put another coat of the glue over the tops of the thumb tack heads to secure it further. I am planning to use nylon upholstery thread lashings to lash all the tacks down onto the top of the 2430 bldc motor tightly and glue the lashings down as well in order to make the thumbtacks even more solidly set into place. Now I'll grant welding them down would be ideal, however, not having a micro tig welder made yet (future project), I just wanted to get going fast and I thought with enough care, it is possible these can be constructed solidly enough with composite material techniques to function reliably. I'm crossing my fingers. We'll see.
>>34087 >while using the best methods I have including silent BLDC motors with silent pulley based downgearing. Good choice. The noise problem is generally one of the big concerns I have.
>>34087 Remarkably meticulous work, Anon. Cheers. :^)
Open file (2.41 MB 2928x3798 IMG_2252.jpeg)
I got done cutting out the pulley discs and drilling them and mounting them to the thumb tacks and gluing them in place with 401 glue using a sewing needle tip as the applicator. They all are reasonably square and solidly in place I think. Everything is moving freely. Everything seems lined up okay. I then mounted them all to the 2430 bldc motor. These thumb tack based pulleys still need to be lashed down well and the lashings (upholstery thread) need to be coated in 401 glue to make them stiff and solid. I also need to add pulley discs to the 2430 bldc motor that are to line up well with the pulley disc slots the string is to go to. I then need to wind up the string sections themselves, loading up the system in preparation for actual testing.
Open file (1.19 MB 2064x2010 IMG_2257.jpeg)
Open file (1.71 MB 2466x2082 IMG_2256.jpeg)
I wound up my 6lb test Hercules PE braided fishing line onto the previous pulley system setup only to find out that the pulley could only handle about 21 inches of fishing line wound onto it before it started to come dangerously close to overfilling the pulley. The aim is to have plenty of the plastic disc overlapping the fishing line even when it is wound up fully to one side because that plastic disc acts as the guide to keep the line in its proper channel. I want at least 32:1 mechanical advantage out of this downgearing so if I want my final output to be 1" then the first pulley has to be able to wind 32" of fishing line onto it comfortably. So I realized at least the first pulley has to be a few more millimeters increased in diameter. So I had to rebuild the thumb tacks arrangement to accommodate these changes and make that first pulley bigger. With this increased size first pulley, I realized I'm getting what looks to be 7:1 mechanical advantage from just the first pulley alone! At least initially when it starts. As the fully wound up pulley gets winched in by the motor, the relative size differential gets smaller which means it will speed up and the torque will be less than the starting torque and increasingly so as the size differential decreases. This will create a natural sort of acceleration effect and high initial power and gradually less power. I think these side effects of this system seem to be quite good but I'll know for sure in testing. The next steps will be to wind up the reverse direction of the first pulley and start connecting the first pulley to the second pulley and so on. I may not even need all 5 pulleys but we'll see. With the first pulley being already 7:1, if the remaining 4 are 2:1 say, then we'd have 7:1, 14:1, 28:1, 56:1, 112:1 so 112:1 would be the final output. That seems quite overkill and perhaps will be too slow. Although very strong. The motor outputs about 0.42 lb on average so .42*112= 47lb! Now the lever of the joint itself makes you lose mechanical advantage due to the fulcrum location etc so it would drop down to say 15lb but my finger individual joint flexion power is only like 5-7lb so that's double mine. So a bit overkill. So I might skip using one of the 5 pulleys. Having it there is nice though just in case we wanted to trade speed for power for some of them we'd then use that one as an optional strength boost we can tap into in the future if we want to trade speed for strength so I might just leave it in the design even if I don't use it just yet. In testing I may find I prefer to use it afterall. Nice to have that option if needed.
Open file (315.17 KB 864x948 IMG_2261.jpeg)
Open file (2.39 MB 2838x2418 IMG_2262.jpeg)
So it turns out that when the forward and reverse directions portions of the thumb tack pulley downgearing system are doing their thing, they won't always have the same mechanical advantage and so will be moving at different speeds. Therefore, I have to treat the forward and reverse pulley systems as entirely separate systems that have to be completely decoupled and handled independently, each pretending like the other one doesn't even exist. They can share the same thumb tack, but have to be decoupled. So I cut the #2 fishing crimp sleeve in half using my miter saw and have to redo the plastic discs phase. Each half #2 fishing crimp sleeve will have 3 plastic discs, one for outside of the larger diameter pulley and one for the outside of the smaller diameter pulley and one to split the two. Three total. And so with 3 plastic discs on each half crimp sleeve we have 6 total discs per thumb tack. We only had to deal with 5 before so things will be even tighter but it's fine. We have enough room. Next, since both sets of pulleys have different speeds that vary over time, the one that is not being actively winched in at any given time will be randomly releasing slack in a chaotic way. This can lead to tangling and all sorts of problems. To resolve this, we need a automatic slack tensioner system to aid the pulley system by keeping this releasing group of pulleys in a state of good tension at all times. This I will resolve by the pictured method. So basically a tension spring connected to a metal eyelet will at all times be trying to pull the fishing line out of alignment and draw slack out of it. So as looseness is detected, it will immediately draw that in removing it from the system maintaining taughtness everywhere at all times. This will prevent the pulleys from getting tangled or anything like that. This setup can be placed anywhere in the path between the pulley system and the joint the pulley system is to actuate.
I hardly know where to start commenting on your work, Anon. You've already done much research, and have what I consider a very innovative plan. I'm very-much enjoying watching the progression of your many ideas into reality, Artbyrobot. Please keep up the good work, and also please keep us here all up to date with your adventures in developing these two robots of yours. Cheers, Anon. :^)
Open file (1.50 MB 2658x2352 IMG_2267.jpeg)
Open file (973.03 KB 1866x1404 IMG_2269.jpeg)
Open file (1.54 MB 2796x1938 IMG_2268.jpeg)
Open file (1.28 MB 2706x1746 IMG_2270.jpeg)
I started some testing on just the first pulley and lots of things went wrong: Twice I had to increase the pulley size because I wasn't able to use enough line winding onto said pulley for my total line draw need after accounting for the 32:1 downgear ratio. I calculated 27" as the very least it has to winch in at the motor shaft to get 0.84" total draw at the joint of the index finger which is perfect (27/32=.84). The pulleys were too small to accommodate 27" winched onto them so I had to increase the size - which meant removing everything, increasing size, then rewinding everything by hand for an hour plus! Just so tedious and annoying! Another failure was one time, the string was too loose on a pulley and a tighter wrap got under the looser wraps and then the looser ones snugged against it binding it down like someone said would happen - which made it all stuck. Also I had many derailments where the string came off the pulleys and started wrapping up on the axle off all the pulleys and getting things quite stuck that way. I've been dealing with carefully untangling and rewinding tangled messes over and over. It's been a disaster. I thought of scrapping the whole thing a couple times. However, after taking a step back, it occurred to me that the tangling issues were largely due to forgetting to put the final outlet of the system under load to tension the whole system which would keep every pulley winding nice and tight and aligned well. So this was user error and oversight, not the fault of the basic concept of the system then. I just forgot to do those parts in my rush to start testing things. I planned to only add that stuff at the very end once the whole system was done and did not think I needed to do that just to start initial testing on a single pulley. That was a faulty assumption and an oversight. The whole system always has to be under tension to work right. My bad. Lesson learned and a valuable one at that. I did not fully grasp until I saw with my own eyes the disasters the importance of keeping it all under tension at all times. Yes I knew theoretically it was needed eventually, but I did not realize the whole thing was absolutely doomed instantly every time if it is not immediately under tension even for a first set of simple tests. That was revelatory for me. I'm glad I got to see the failures first hand though because it enabled me to study what failures can be expected when tension is not placed and know intimately first hand the importance of tension and how lack of tension causes the failures specifically. Valuable to see it with my own eyes instead of only imagining it. This has helped me come up with some cool derailment prevention and loss of tension prevention mechanisms to fool proof my system more - even beyond the tension spring drawing shown in my last post. Note: At the top of the motor output shaft, you can see two large pulleys where I have wound 2 pulleys for moving the motor axle clockwise and counter clockwise to simulate the motor moving. These are temporary windings just for testing manually without messing with electronics for now. These need to be fed in under tension at their inlet and their inlet needs to have a eye positioned in front of it that forces the string to stay in line and not feed in astray out of alignment. So also the pulleys for the main motor output shaft pulley for flexion I'm testing and the first pulley downgear I'm testing. Every place a string enters a pulley needs to have a small eye that guides the string onto the pulley perfectly in alignment with the plastic discs of the pulley and prevents it from derailing. I noticed that when feeding string into a pulley I intuitively hold the string between thumb and index finger and pull the string away from the pulley as its being fed into the pulley to apply tension on the line and tight wraps on the pulley. I also align the string with the center of the pulley and hold my fingers at a minimal distance away but not too close. You want the string to be able to easily angle up and down from your finger pinch point to ride up and down the height of the pulley creating layers of wraps evenly as opposed to all wrapping in one area and not having a well distributed wrapping. If you study how to wind a bobbin on the top of a sewing machine, you see the string take 3 turns and go through a metal wheel that places tension onto it and only then does it enter the bobbin which it then winches onto the bobbin rapidly to wrap up the bobbin with string. These are all designed to create tension from the otherwise loose and floppy string leaving the main spool of thread you are feeding into your empty bobbin. I need to create a similar type of tension system to feed onto my pulleys which are acting just like that bobbin and need the same type of setup to succeed. To create the eye that centers the string and forces it to neatly stay on the bobbin and not derail so easily, I plan to use 28 ga tinned copper bus wire. I will cut out a small section of that wire and glue it to the base platform the thumb tacks are glued to and then run it vertically and then form the eye shape that acts as a guide and derailment preventer. The eye will just be a oval with a couple legs glued down with 401 glue to hold that oval into position. For the tension maker, I'm planning to use just a couple windings of tension spring with two small square pieces of plastic which will sandwich together and be pinched together snugly by the tension spring and the fishing line will be fed through this. I will use the same produce container plastic I'm using for the pulley discs. The fishing line will not be abraded/damaged by this in theory but only some pinching force applied to it to give it some tension and cause its feeding action of winching onto the pulley to be tight and snug to help prevent derailments and tangles and loose wraps. This system is meant to emulate and replace holding the string snugly between thumb and index finger as it's fed into the pulley tightly.
>>34224 >Valuable to see it with my own eyes instead of only imagining it. You have a great analytical mind, Artbyrobot. You're able to dream up good ideas, and then figure out how to approach implementing them. But nothing matches experiencing when "the rubber meets the road". Imagination is by far the most important, but as they say 'experience is the worst teacher', and 'hindsight is 20/20'. You're making progress, Anon. Keep it up! Cheers. :^)
Open file (2.41 MB 2622x2328 IMG_2274.jpeg)
I managed to implement a friction device for both main manual input pulleys for manually turning the motor shaft and one for creating tension on the system at all times. The former I made by just running the fishing line through a tension spring between the coils which pinched the fishing line enough to provide friction and feed it snugly into the motor shaft as it winches it. This successfully replaced the need to feed it in by hand between thumb and index finger with snug pinching action to get it to winch in tightly. For the tension on whole system need, I ended up just hanging a bolt from the final output string which put the whole pulley system under light tension. You can see the tension springs sewn into the bone fabric on the left hand of the pulley system in the attached photo. You can also see the thread going through those if you look carefully. You can also see the output pulley on the right hand side of the system and see the little metal 28ga wire eyelet I made and the string being fed through that eyelet as it heads toward the camera lense shooting the photo. It then drops down out of sight. So you have to visualize it tied to a bolt. The bolt is currently taped off to a piece of bone since I removed the tension after testing to do some repairs. So to the results: with these little modifications, the testing went much better. It was fairly reliable. The only times anything tangled up was when the bolt caught on something when I wasn't paying attention which relieved the pulley system momentarily of the tension created by the weight of the bolt pulling down by gravity and tensing up the system. As soon as the system lost that tension, it began to unravel and created a tangled mess. This happened a few times in testing and was user error. Although one time a pulley just stopped turning randomly despite the tension created by the bolt. That concerned me alot. I don't know if something got wedged in it or it was cockeyed just right or what but sometimes it gets stuck a bit. That cannot happen ever or the whole thing fails. Perhaps greasing the inside of the fishing crimp sleeve would prevent this from happening anymore. Also, the bolt is not THAT heavy. Using something with a bit more tension force placed onto the system could also help some more perhaps. I think using a tension spring as the tensioner - as shown in a drawing I posted previously - will be just the right amount of tension. I think it might pull a bit harder than the weight of the bolt was pulling. So between those two improvements I think this rare fluke will be avoided. And so far, as far as I've seen, as long as the pulleys spin freely and no tension is lost, everything appears to work perfectly. I was able to go back and forth with no issues many times besides the few screw-ups I already mentioned. So the system appears to be a success so far from testing. I can now move onto building pulley #2 and 3 and testing them thoroughly in conjunction with pulley #1. Also of note: I thought pulley #1 was a 3:1 ratio and perhaps it is at times, but the mechanical advantage ratio changes over the course of the winching process because the larger pulley gets smaller as it unwinds and the smaller pulley gets bigger as it winds up. So their relative diameters changes. Therefore, I guess we have to treat it as what is the average mechanical advantage it produces. Well in the final measurement, it cut down the original 27" of string being winched in to 13" of string on the final output. Trading down that distance of travel is the key to the creation of mechanical advantage. We want the final output to be around 0.84". We want 32:1 mechanical advantage in the end. So pulley #1 got us to 2:1 mechanical advantage only so far. The next pulley likely will get us to around 4:1 and the next one 8:1. I am considering just stopping there. I have room for two more pulleys, but at the moment I'm considering doing the last two down-gears with my Archimedes downgearing pulley design. I think that method might be a little more robust and I kind of just want to use both methods at this time. Both have their pros and cons. I feel using both methods can help me learn which one is superior and learn to perfect both as I see which one is more durable long term, which one has more incidents, which one tangles from time to time and why and resolving those issues if they come up. The great thing is this: the compact pulley method (thumb tack method) is giving us 8:1 downgearing roughly. Of the 27" of total draw, that brings output draw at that point down to 27/8=3.37". So the final two downgearing stages will be reducing 3.37" draw down to 0.84" draw. So 3.37"/2=1.68" then 1.68/2=0.84". So the Archimedes pulley system only needs TWO pulleys (down from whatever huge number we had before in our previous monstrosity of wraps and turns we had to do). To make just two pulleys is a piece of cake. Also, given 3.37" is all we are working with for the first pulley, and the pulley is equidistance in the center of that stretch, the total draw length of the two string halves wrapping around that first pulley is only 1.68". And the next pulley's total length is .84". So 1.68+.84=2.5" give or take is the total length of the pulley system for this. This edition of the Archimedes pulley system adds 4:1 downgearing to the compact thumb tack pulley system's 8:1 downgearing. Giving us a total of 8x4= 32:1 downgearing. That 2.5" total length Archimedes pulley system setup is so small compared to my original 16:1 Archimedes pulley system I published earlier that it is a lot more practical to use and we still save a ton of space.
Note: I could do the rotate in place style pulleys but just put them on the forearm instead of the motor as the motor is already getting quite cramped and tedious to work with. Or I can do Archimedes pulley system style with pulleys that move lengthwise along the forearm. Both styles are good. I lean toward the latter though at this time. Both would work though. I kind of just like the variety for learning purposes but I'm not 100% sure on this decision. Note: an advantage to completing the final 4:1 downgearing on the forearm closest to the finger joint is the total distance of string travel from the motor to the finger joint and the total bends it takes all adds friction and when that friction is placed with a large force on it, it is harder on the teflon guide tubing. But by only doing partial downgearing at the location of the motor and saving the next phase of downgearing for being closer to the finger joint in question, we avoid a lot of forces and frictions in the teflon guide tubing running longer distances to get to the finger. In some cases, I have motors intended to actuate finger joints placed in my CAD as far away from the finger joint as the upper spine area and some in the lower latimus dorsi area! That is a LONG travel to go across the torso, past the shoulder, down the humerus, past he elbow, down the forearm, and then FINALLY to the finger joint it is actuating. That is a LOT of friction and turns introduced. So to navigate such long distances, it is ideal to have it be just high speed low torque during that time-frame and only beef up the torque with downgearing NEAR the finger joint it is actuating. Note: the fishing line selected for downgearing while in the early phases of downgearing gets to be very fine low test strength fishing line like the 6lb test braided pe fishing line I'm using here. However, as the downgearing progresses, trading speed for torque, so also the fishing line selected for these sections needs to progressively get larger in diameter to accommodate the higher tensile forces involved. So we'll be graduating from 6lb test to 20lb test then 70lb test then 130lb test. So we'll be changing fishing line diameter 4 times in the routing from the motor output shaft to the joint itself! That said, keeping the downgearing near the motor minimal is best since it enables us to use the finer diameter fishing line for the long travel distance from the motor to the finger area. Then only once near the finger do we do the final downgearing stages and beef up to the larger diameter fishing lines. Then another advantage to all of this is the teflon tpfe guidance tubing we are using as guide tubing gets to be smaller diameter guidance tubing for those long fishing line runs. This saves space and enables us to make tighter turns without as much consequences in terms of wear and tear on those turns and tension/friction concentration at those turns. Also, when making turns AFTER full downgearing, the higher forces involved tend to want to crush and deform the TPFE tubing - which is why sometimes metal spring is used on the outside of the TPFE guidance tubing to make it into a Bowden cable and reinforce it to make it non-collapsible under the high tension forces that get involved by that point. We avoid all of this by keeping the downgearing at the location of the motor more minimal. Note: that all said, our downgearing at the location of the motor thus far is planned to be 8:1. The motor outputs .45lb at our distance from the center of the motor shaft roughly. So 8x.45= 3.6lb of tension force as the output at the motor then. This means we get to use our 20lb test fishing line for the long travel from the motor to the distal forearm where we will do the final 4:1 downgearing bringing us up to 32:1 downgearing. That 20lb test line is only 0.2mm diameter so it and the TPFE guidance tubing we pair with it is very fine and can easily weave its way past everything and get to the distal forearm without taking up too much space or having to be reinforced by metal spring to prevent crushing or distortion of the TPFE. At least not in theory. If this proves not true, I can always add metal springs to any sections that are getting crushed or distorted to reinforce the outer diameter of the TPFE guide tubing in those areas - probably areas near tight turns? We want to take as few turns as possible though and make the turn radius as large as possible to cut down on friction as much as we can during the fishing line routing runs.
Open file (9.61 MB 637x358 IMG_2276.gif)
This is a slow, careful hand test of the pulley. Everything looks good. Also, I did fast tests but didn't capture a nice shot of those with good hd closeup like this. In any case, this can show you some idea of how it all looks in action so far. The motor shaft is not turning electronically but is being turned by me pulling string wrapped around it to screen left is my hand pulling. To screen bottom is a hanging bolt that is being winched (not shown its cropped out of the image). I wanted to avoid working on the electronic actuation which is a rabbit hole in itself until I have the pulley system fully done and tested. THEN I will make it all work electronically as the next phase.
Open file (255.59 KB 934x645 IMG_2277.jpeg)
After further deliberation, I have concluded that I should put 4:1 downgearing on the motor's top with the turn in place pulleys and put 8:1 further downgearing located nearer to the joint being actuated - in this case the distal forearm. My reasoning for this is as follows: the routing from motor to near the joint is facing turns and friction etc and these become smaller factors when under lesser loads. So leaving things more high speed low torque initially during this phase of the routing is advantageous to lower friction and issues relating to deformation and compaction on the guidance tubing. This means less wear and tear and lower maintenance as well. Next, the turn in place pulleys are quite difficult to work with being very small and compact and lots of winding and whatnot is hard to deal with and tedious. Further, the turn in place style, when fully winched in has a much lesser downgear ratio compared to when fully extended due to the relative diameter size ratios of the pulley pairs involved changing in size during the winching. Whereas in the Archimedes pulley downgearing system the mechanical advantage is fixed and doesn't change during the entire flexion nor extension process. This makes it more reliable and limits our losses during the near end of the winching phase that are incurred in the turn in place technique. This ensures we retain adequate mechanical advantage during all times. Another important update is I have added axial rotation to the proximal finger joint in CAD. My index finger has a little bit of this type of control to it so I think it will be a nice boost to control and dexterity for the robot. Really maxing out the ability of the robot to finely manipulate its finger positions and improve performance of the fingers at all tasks. I added the necessary 4 additional motors to achieve this into the CAD as well. You can see the highlighted pair of axial rotation red indicator arrows which show the angle and location of the tendons from where they terminate to where they will exit the guidance tubing - the range of motion if you will. Yet another important update is I now plan to just use a spring for the extension actuation force rather than the reverse direction turning of the motor. This is admittedly going to give the extension less strength and the flexion less strength. The flexion will have less strength because it is now fighting against the extension spring to get the finger to flex. The extension will have less strength because a spring alone is making it happen rather than a strong motor making it happen. I don't mind either of these trade-offs though because it will greatly simplify the routing - cutting it in half, simplify the motor mounted pulleys, cutting it in half, and simplify the Archimedes pulley systems, cutting the amount of them we have to make in half. That is just a massive amount of time and effort saved. I just am not convinced that spending that level of time and effort just to have a stronger extension of the finger joints is worth it. Relatively passive spring powered extension of fingers is very common in hobby humanoid robot hands from what I've seen and although I've always viewed it as a lazy solution, I do see some merit in embracing more simplicity at times. Especially if you cannot JUSTIFY the added work of the alternative. The more I think about when I have needed finger extension to be very strong, the more I find that it seems to be a relatively rare occurrence. It just doesn't seem to happen often. Now as the robot grows more able with its AI and more sophisticated, and gets into more and more types of work, the occasional scenario where fully powered extension of fingers will start to crop up more and more as a need. So at that time, I am thinking we can revisit this and get the extension actuation installed. So I still plan to reserve space for it on the CAD and ensure it can be done without any major problems or redesigns needed. It should be a smooth and straightforward upgrade option. But for a minimum viable product that can meet all of my goals, it is not necessary to implement in this stage of development. In fact, it is also possible to just have the robot install these on himself once he's building the rest of his own body. Which means me doing it would be a waste of time if the robot could do it later instead of me. So in any case, this acts as a MAJOR shortcut and time-saver for me and will be a big game changer IMO. I'm excited about it. These types of big shortcuts really move the project forward in development very rapidly in large leaps saving countless hours and I love them. As long as they aren't shortcuts that will come back to bite us later, I'm okay with them. I don't think this one will bite us later so I say let's go with it! Note: it also just occurred to me that the robot could potentially have the extension actuation be in the form of geared n20 motors instead of reverse direction of the main 2430 bldc motors with pulley based downgearing. This would save alot of work but introduce noisy metal gearing to the robot. The reason I think this is okay to do is that these geared n20 motors would be slack lined and not interfere with fingers AT ALL nor be used on any way at all UNTIL the fingers need strong extension actuation - which as I said is incredibly rare. In this rare event, it tapping into these geared n20 motors for some extra oomph to get the extension to actuate harder would solve the problem and the little noise it created would be a rare occurrence type of noise. It would hardly be noticeable then and 99.999% of the time you'd never encounter this noise. The bigger issue would be noise in a common feature like blinking. Now THAT is annoying to hear gears EVERY TIME the robot blinks.
Open file (3.52 MB 2934x3672 IMG_2279.jpeg)
I have added the final pulley and rigged the guidance TPFE tube up to that pulley and routed that to the general vicinity of the Archimedes pulley downgearing system. As seen in the photo, I used super glue and post it note paper to form a TPFE guidance tube support structure to hold it in place as well as wrapped it in fabric tape and soaked that tape in super glue. I applied the super glue with the tip of a sewing needle as a precision application method. The next step will be to test the pulley system as is and make sure everything is working really well. If all testing passes, we will then modify the Archimedes pulley system on the forearm that we were using before to simplify it some since it now deals with only 7" or so of string compared to 27" of string it dealt with when we did not have the turn in place pulley system in place. So it will now be much more compact and fewer pulleys needed in it. So a bit of redesign and part recycling and we'll be good to go on that. Also, before, it was a 16:1 Archimedes pulley system whereas now it will just be a 8:1 system.
>>34260 >so I say let's go with it! I concur. Nice advance, Anon. Thanks for sharing it with us here. Cheers.
Open file (1.25 MB 2832x2502 IMG_2282.jpeg)
I just ran a test of the second turn in place winching pulley and ran into several problems. First I noticed my main lines turning the motor were not the full 27"+ which I thought they were but just remeasured and found they weren't. My bad. So I have to rewind those to fix that. Next, I noticed that just as we depart from the motor output shaft we experience mechanical advantage with each downgearing, so also when traveling from the downgeared area back to the motor output shaft we experience mechanical disadvantage. Up-gearing. Which means the bolt hanging as a load to place tension on the pulleys during a release cycle was not enough weight anymore (was barely enough before now clearly not enough). Now note that the bolt represents what a tension spring will normally be doing, tensing up the winch system to keep it all solid and tight. I don't want this to have to be much heavier than the bolt. I want the system to not need much pulling to remain good in tension. The friction of the teflon tubing plus mechanical disadvantage etc was causing the pulleys to not remain tense (and their not being lubed yet on the junction between fishing crimp sleeve and thumb tack. So my solution I'm now contemplating is either moving one of the turn in place winches down to the location of the Archimedes pulleys on the forearm area and putting the tensioner apparatus between it and the previous pulley mounted on the motor so that the tensioner apparatus does not suffer as much mechanical disadvantage due to up-gearing OR I get rid of the second pulley entirely and just have the winch in place be a single pulley 2:1 and the Archimedes system be 16:1. Which still works as we have then 32:1 which is great still. Under such a system, the original 27" winching would be reduced to 13.5" by the winch in place pulley attached to the motor. The Archimedes pulley system then needs to go down, around one pulley, back up, around another pulley, then down and around another pulley, then back up and tie off. The total travel for those one down, one up, one down, one up (4 trips) is 13.5/4 so 3.4". And we'd sit at 8:1 at that point. so adding two more pulleys beneath that first group would add another 4:1 for 32:1 total. And those two pulleys would add another half inch tops so that gives us around 4" total length of the Archimedes system and not too crazy many turns in that first system like we had in our first prototype. Still quite simplified comparatively speaking. So this is a very viable solution. And that 4" is around 10cm and we had 11cm already planned for this purpose in the CAD in the forearm from before. So we are still within that target and viable still without any change to the CAD at all which is great. Anyways, back to the test's issues discovered. Oh yeah, also, the load (in this case a bolt hanging) struggled to keep the turn in place winches under tension while the motor was releasing the bolt (loosening or unwinching itself) not only because of the mechanical disadvantage from the pulley upgearing itself and from the friction in the TPFE guidance tubing but also from the friction of yet another pulley and its friction between its fishing crimp sleeve and its thumbtack. So I was having to manually pull down assisting the bolt, pulling down fairly hard just to get the system to stay taught and release without becoming a derailed tangled mess. One other work around if I were insistent on going with more than one winch in place pulley would be to wind up extra line onto each turn in place winch pulley and have that directly attached to a tensioner spring placed wherever on the robot. This would always keep tension on just that winch in place pulley and be responsible for just that pulley and suffer no mechanical disadvantage beyond the TPFE guidance tubing it has to pass through to get there which shouldn't be too bad if the spring can be nearby. This is a valid solution but adds another layer of complexity to the winch in place pulleys and now more routing and string to deal with. It also means loads of extra springs to place. Attached is a drawing of the proposed tensioning mechanism for tensioning each pulley individually. In any case, were I to add this type of tensioning apparatus to each pulley and the necessary extra plastic disc and vertical spacing to glue string to the fishing crimp sleeve and wrap it up, that takes up even more vertical space in the system and we were already really lacking sufficient space as is. So to gain the extra space needed to do that, we'd have to extend the height of the fishing crimp sleeve to accommodate this which would then remove the option to add the reverse direction set of pulleys to the same thumb tack. Although that is probably fine now that we were planning to achieve that with just a tension spring as the actuator for extension of fingers instead of motor actuated extension and coupling that with a n20 gear motor for extra oomph in demand on a rare as needed basis for extension action when the tension spring is not strong enough to do it for the task at hand (rare). So yeah, this apparatus would work to solve the issues I'm having with my current test setup I think. But just going 16:1 on the Archimedes instead of 8:1 on the Archimedes pulleys and simply deleting the second winch in place pulley on the motor seems like the best option to me right now. Doing so means the Archimedes pulleys bumps up from 27/4 = 6.75" for Archimedes pulleys to deal with 6.75/4 (for up and down passes around first group of pulleys) so 1.68" in length then another pulley brings it to 2.1" total length compared to 27/2 (only one winch in place pulley) = 13.5" for Archimedes pulleys to deal with 13.5/4 (for up and down passes around first group of pulleys) so 3.4" then add 2 more pulleys so 4.2". So 2.1" vs 4.2". If we keep the second winch in place pulley we shave off 2.1" in Archimedes pulley system total length and shave off one pulley from its system too. Well I think just going 16:1 on the Archimedes is my move here.
>>30954 You have a problem with miniskirts? What, so you can't play Tennis? What about Star Trek?
>>34280 I hope you can devise a tiny & robust little tensioner mechanism that serves you well in keeping thing running smoothly through your spindles, Artbyrobot. This is clearly going to be an important function within your designs. <---> Otherwise, you're continuing to make incremental progress here. Please keep it up! Cheers, Anon. :^) >>34348 Please leave the man in peace. Alternatively, you could even help contribute something productive here on /robowaifu/ instead. :D Sound good, Anon? Cheers.
Open file (3.70 MB 3024x4032 IMG_2288.jpeg)
Okay so here is my latest iteration of my motor mounted winch in place pulley downgearing setup completed. I ended up doing a total overhaul of everything since my last iteration failed. In this iteration I made many small improvements. One thing I noticed is that the thumbtack shafts have a little bulbous section near their tip and I reasoned that perhaps this can catch on the #2 fishing crimp sleeve and impede it at times. So I sanded it off with a nail file so the whole shaft is now a cylinder with no protrusions. When I tested the rotation with the fishing crimp sleeve after this modification, it spun more freely than ever before by a long shot. So I think I'll do this every time going forward. Another improvement is I added more height to the sections of the pulley, taking up all the available vertical space that used to be planned to be used for reverse direction actuation which is now being done by a tension spring instead. The added vertical space on each pulley means that contiguous loops of string wrapping have more space and so the diameter taken up by the string as it winches doesn't change nearly as much as before which means it will have more consistent downgearing through the whole duration of the winching cycle. I prefer this. It is also easier to work with for gluing on the discs and whatnot with them more spread out. Another improvement is I added an extra pulley set on the top of the main winch in place pulley which I will use to attach a string which will be tensioned on one end by a spring and the purpose of this will be to put tension on the system to prevent derailments and ensure tight wrapping every time the winch releases its string (finger extensions). Now I may not actually need this extra tensioner pulley if the spring on the finger doing the extension actuation provides enough tension to the Archimedes pulley system and this winch in place pulley to cause them all to remain snug and tensioned, however, I think I probably should tension this winch with an additional tension spring dedicated to it exclusively even if it is just a redundancy just to play it safe and doubly ensure we get no derailments even when some issue may come up with the Archimedes pulley system. Last thing we need is a cascading of failures like Archimedes system fails so also winch in place pulley then derails and tangles so then we are really set back in the event of some unexpected issue. So better to have this redundancy. To provide constant tension on the winch in place pulley, I have considered using elastic thread used for making DIY necklaces, using a tension spring, and using a clock spring. The latter seems like it could be the best and most reliable option due to its constant tension. I bought a few sizes to experiment with from Aliexpress. Search terms to purchase such an item were "flat spiral coil constant force spring". They are around $2 each. Considering the motor is $24, $2 to have a extra spring isn't too bad. It could really make or break the reliability I think. Now the issue is the spring is suppose to provide tension for all 32" of travel of the winch. That is a long way. My mini tape measure surely has this type of spring in it and it has that tension spring the whole time and presumably uses the same type of spring I just bought. So it is possible for a tension spring to do this for this length of travel. So hopefully one of the ones I bought works for this. If not I may have to upgear it trading tension for more travel distance. I will have to fit these extra springs into the body which may be tough. Space is VERY constrained but hopefully we can pull it off without any issues. In any case, these are going to take a few weeks to arrive so I'll be testing without it at first. Another improvement is I made the diameter of the larger pulley of this turn in place winch bigger which means it will provide more downgearing. Not sure how much maybe an extra 5% or w/e but it's something. I have routed the final output string using the TPFE tubing around the side of the elbow this time and then across the forearm and over to where I have setup my Archimedes pulley system from before. This Archimedes pulley system is getting a total overhaul. Many improvements planned for it. So that is up next, overhauling that. And then I will be ready to connect the turn in place winch pulley and its 2.4:1 or so downgearing with the 16:1 Archimedes pulley downgearing to achieve around 38:1 downgearing in total.
>>34364 This all seems pretty amazing if you get it working. I thought the idea of your tape measure keeping a constant tension both in and out is a good idea.
>>34365 I was suggesting using the same type of coil spring mechanism found inside a tape measure, not using an actual tape measure itself with the measurements at all. Although the latter can be done, I suppose, it would not be as space efficient and it would be a lot more expensive as well.
Open file (1.21 MB 1422x1266 IMG_2290.jpeg)
Ok so I've been now working toward creating the latest iteration of the Archimedes 16:1 pulley based downgearing system and as part of that I decided to remake some of the pulleys with grooved outer races as I had discussed previously wanting to do - in order to prevent the fishing line from walking to a corner of the pulley and wedging itself in between the bearing and the plastic disc sandwiching in the bearing and becoming jammed that way. Previously, we had glued in a very tiny piece of clear thread to block this gap anywhere I found the tendency for jams to happen, however, to create a grooved outer race from the outset is going to prevent this issue all together! So to do it, I took my little 1x3x1mm ball bearing and pinned it down with my left thumb against wax paper on top of a stack of post it notes, so holding it all with my left hand in the air. I used my highest zoom on my visor magnifier to see what I'm doing. I then loaded very tiny amounts of super glue onto my xacto knife with sewing needle tip instead of blade tip and using this sewing needle tip, very carefully placed super glue into the joint where the ball bearing outer race meets the wax paper. I did this for about 1/3 of the bearing then carefully lifted off the pressure of my left thumbnail pinning it down and rotated the whole thing then repinned the bearing down again with my left thumbnail and repeated the process of adding glue little by little. When one side was done, I was able to carefully peel it all up from the wax paper, flip, and do the other side. This needs to be carefully trimmed down still but the idea was a massive success. The bearing still spins freely and the grooved outer race is done! That fishing line can't go ANYWHERE now to jam anything! The photo is just the ball bearing and the glue. So the plastic discs will now be able to go over this and the fishing line won't be able to walk across the outer bearing surface and jam itself between the bearing and the plastic discs anymore! Note: my concern about this procedure was that the glue could potentially walk underneath the bearing and glue the outer race to the inner race and thereby ruin the bearing - but this did not happen! The gap between the underside of the bearing and the wax paper which were both firmly pressed together by my thumbnail was too tight for the glue to travel into there and ruin anything. So the glue only went where I wanted it - which is on the outer race of the bearing forming the intended groove on that outer race. A huge success. I used 401 glue btw.
>>34391 >This needs to be carefully trimmed down still but the idea was a massive success. >I used 401 glue btw. Great job, Anon! Glad to hear you successfully managed this process for such meticulous work. Will you need to repeat this for other pulleys? If so, can you think of some semi-automated way to perform the task to help reduce your load, and also to increase the likelihood of a quality job? Something like some kind of jig (or rig) is what I had in mind. <---> Regardless, glad to hear of the new progress Artbyrobot. Please keep it up! Cheers. :^)
Some more kind of automated way would be nice, however, it really didn’t take that long for this particular stuff at all. Maybe two minutes tops. In any case I wouldn’t start getting into jigs and automation type of stuff until I’ve proven out the entire system with extensive testing and I know for 100% sure I’ll be using this approach. There is still a tiny possibility pulleys fail for some unseen reason and I have to go with metal gears after all and just give up on the idea of a quiet robot. But I’m strongly hoping that will not be the case.
>>34406 >...and I have to go with metal gears after all and just give up on the idea of a quiet robot. But I’m strongly hoping that will not be the case. Yeah, me too Anon. Keep forging ahead, Brother! :^)
Open file (1.82 MB 2616x2610 IMG_2297.jpeg)
Here's a better image of the grooved outer race with more refinement. To refine it I cut away excess glue with an exacto knife and then sanded it with a nail file a bit to smooth it out.
>>34424 It's so tiny. Impressive work, Anon. I truly hope this approach works out -- for everyone's sake. Keep moving forward! Cheers. :^)
Open file (1.72 MB 4032x3024 IMG_2299.jpeg)
Ok so I was struggling to plan out how the flat spiral coil constant force spring would maintain constant tension on my first winch in place pulley the past couple days and I was studying how tape measures use these springs. Then it hit me when a colleague was mentioning belt pulley based downgearing that a belt pulley based downgearing for this first pulley would remove all the issues of derailment and need for constant tension during whole duration of travel a winch style would require in this design. Also, since its just .4lb-.8lb of force for the first pulley downgear, as long as the belt is reasonably tensioned and has some decent grip to it, I should not deal with a ton of slippage issues and the motor's output should be passed along well. So here is my beginning attempt at converting my first pulley to a belt based pulley instead of fishing line winch based pulley. This is made just using adhesive transfer tape applied to one side of a nitrile glove and cut out into a 1.1mm wide strip and applied to the two pulleys directly. Built in place. Early testing shows it needs more layers to have less stretchiness or needs to be reinforced internally with fishing line wraps between layers to prevent so much stretch to it which causes slippage. Also, the motor output shaft acting as the winch pulley is a combination of a bit too small in diameter and a bit too smooth to create a proper grip. So I'm thinking of thickening it up some and adding a grippy surface to it so that it grips the belt better with less slippage. I am considering using silicone rubber to coat the motor output shaft or several wraps of nylon upholstery thread and super glue to thicken it then coating that with carpet anti-slip paint. Or silicone. I'm considering making the belt from a cloth coated in silicone or carpet anti-slip paint and then sewn tightly into place over the pulleys - creating a sewn seam for a tight grip. I'm considering a tensioner pulley but I think that's overkill and should be avoided unless it proves absolutely necessary. I have not explored purchasing options at this time but of course I'm open to look into this in the future. The thing about a premade is it would have to be a perfect fit in both length and width and I'm not sure if that will be easy to find or not. This is all a very new approach so I can investigate that later. For now I'm happy to just move quickly on the prototyping with materials on hand.
Open file (276.08 KB 775x579 IMG_2324.jpeg)
Open file (305.94 KB 775x579 IMG_2323.jpeg)
Ok so my belt drive system from my last update just is not quite up to par in terms of grip and anti-slippage. So my new series of changes are planned out and underway now. First, I will be bumping up the height of each pulley to 2mm up from 1.1mm. This will double the surface contact area for way more belt grip in and of itself. So then I can use a 2mm wide belt. Next, I'll be increasing the drive pulley diameter to 1.5-2mm additional diameter. This will also greatly increase surface contact with the belt for more grip. Then finally, I'll be using a commercial belt that is said to have the highest grip of all belts - its called a polyurethane belt. It is a flat belt with 2mm width and .9mm thickness. It should be a huge upgrade to my current setup! The best part is you can customize the diameter of the belt by melting the two ends together! This was a key thing I did not know! So I can create just the right size and it should be perfect! I can also double these up by melting two belts layer by laer for a 1.8mm thick square shaped belt that is even less stretchy and so can be even more able to tightly grip my pulleys. I'm very excited about this and think it will take us to where we need to be *crossing fingers*.

Report/Delete/Moderation Forms
Delete
Report