Artificial muscle

tesla3227 · Post by **tesla3227** » Tue Mar 14, 2023 1:12 am

As an inquisitive person and having invented many things myself, I would like to discuss what I intend to work on to further doll development and making them even more realistic. I have been working in the electronics industry in one form or the other for over 30 years and I believe artificial muscles are the key to getting rid of servos and all the gear driven mechanics in dolls heads, bodies, etc. I am going to be working with various polymers and other products to see if I can produce a product that is not only able to be formed to any shape, but will reliably contract and expand with various, controllable electrical signals. Human muscle is controlled by our brains and electro chemical stimulation so I think it would be feasible to infuse a reactant that is electrically responsive in silicone or other non harmful polymers. Some work in this field has been done, but I think a more advanced yet simple approach is necessary. I believe a capacitance approach is necessary in this case and this is the approach I intend to take. I'm not saying it will be easy, but it's something that intrigues me to the point to where I just have to try. The thought of these dolls moving without the jerkiness and having a more organic feel is definitely exciting. I do work a full time job so this will be something to work on in my spare time, but so very worth the effort! I originally wanted to develop this for people who have lost limbs due to combat injuries or disease, but I think it could be applied to numerous things. I certainly intend to give it a shot. Sincerely, Tesla3227 P.S. Let me know what you think!

Socratus · Post by **Socratus** » Tue Mar 14, 2023 11:49 am

Sounds great. I noticed when bending a doll's arms or legs there is no muscle change in the underlying form as you would get when a human moves his limbs. As an artist who does some figure work, this is a bit disappointing. Your idea, if it succeeds might change that. Good luck.

King Solo · Post by **King Solo** » Tue Mar 14, 2023 4:47 pm

This may be a little off topic, but I don't know why manufacturers haven't created an entire doll made out of a gelatinous core material, with a thin layer of TPE over the top of it. I don't know if it's just laziness, or if they're afraid it'll get damaged to easily. Whatever the case, they need to start innovating new ways of creating dolls outside of the old solid single pour construction. At least it'll be a start in the direction this idea is headed in.

tesla3227 · Post by **tesla3227** » Mon Mar 20, 2023 11:06 pm

Socratus wrote: ↑Tue Mar 14, 2023 11:49 am Sounds great. I noticed when bending a doll's arms or legs there is no muscle change in the underlying form as you would get when a human moves his limbs. As an artist who does some figure work, this is a bit disappointing. Your idea, if it succeeds might change that. Good luck.

I noticed that too, but when you think about it, it kind of makes sense. Muscle moves independently from skin with just a thin layer attaching the two. In a doll, the illusion of muscle is just in the sculpt itself so not separate at all. Hence when you bend the doll's arms, it's just a solid piece of tpe or silicone bending at a metal joint.

Technician · Post by **Technician** » Tue Mar 21, 2023 1:53 pm

I've been saying for years motors and actuators are not ideal, maybe for the Terminator, but not a sex Android. The approach I'm working on is pneumatic with air muscles and air bags, which is "less" noisy. Really looking forward to seeing what you come up with!

randomname1 · Post by **randomname1** » Sun Mar 26, 2023 1:19 am

tesla3227 wrote: ↑Tue Mar 14, 2023 1:12 am As an inquisitive person and having invented many things myself, I would like to discuss what I intend to work on to further doll development and making them even more realistic. I have been working in the electronics industry in one form or the other for over 30 years and I believe artificial muscles are the key to getting rid of servos and all the gear driven mechanics in dolls heads, bodies, etc. I am going to be working with various polymers and other products to see if I can produce a product that is not only able to be formed to any shape, but will reliably contract and expand with various, controllable electrical signals. Human muscle is controlled by our brains and electro chemical stimulation so I think it would be feasible to infuse a reactant that is electrically responsive in silicone or other non harmful polymers. Some work in this field has been done, but I think a more advanced yet simple approach is necessary. I believe a capacitance approach is necessary in this case and this is the approach I intend to take. I'm not saying it will be easy, but it's something that intrigues me to the point to where I just have to try. The thought of these dolls moving without the jerkiness and having a more organic feel is definitely exciting. I do work a full time job so this will be something to work on in my spare time, but so very worth the effort! I originally wanted to develop this for people who have lost limbs due to combat injuries or disease, but I think it could be applied to numerous things. I certainly intend to give it a shot. Sincerely, Tesla3227 P.S. Let me know what you think!

So I had a similar idea but just to improve the realism of the doll's passive motion during playtime with no electronics. The doll's are relatively stiff during playtime I'm assuming because their skeletons are stainless steel with hinged joints. How difficult do you think it would be to just incorporate a spring at each of the main joints? I have a traditional animation background, and in animation, there is a concept called "overlapping action." This is what is missing in rigid doll motion, except for the boobs because they are flexible. I believe springs would add this overlapping action when they're absorbing oscillating force during play. Here's a simple example of the animated motion concept: https://www.youtube.com/watch?v=4OxphYV8W3E

tesla3227 · Post by **tesla3227** » Mon Mar 27, 2023 5:19 pm

jr_geppetto wrote: ↑Sun Mar 26, 2023 1:19 am
tesla3227 wrote: ↑Tue Mar 14, 2023 1:12 am As an inquisitive person and having invented many things myself, I would like to discuss what I intend to work on to further doll development and making them even more realistic. I have been working in the electronics industry in one form or the other for over 30 years and I believe artificial muscles are the key to getting rid of servos and all the gear driven mechanics in dolls heads, bodies, etc. I am going to be working with various polymers and other products to see if I can produce a product that is not only able to be formed to any shape, but will reliably contract and expand with various, controllable electrical signals. Human muscle is controlled by our brains and electro chemical stimulation so I think it would be feasible to infuse a reactant that is electrically responsive in silicone or other non harmful polymers. Some work in this field has been done, but I think a more advanced yet simple approach is necessary. I believe a capacitance approach is necessary in this case and this is the approach I intend to take. I'm not saying it will be easy, but it's something that intrigues me to the point to where I just have to try. The thought of these dolls moving without the jerkiness and having a more organic feel is definitely exciting. I do work a full time job so this will be something to work on in my spare time, but so very worth the effort! I originally wanted to develop this for people who have lost limbs due to combat injuries or disease, but I think it could be applied to numerous things. I certainly intend to give it a shot. Sincerely, Tesla3227 P.S. Let me know what you think!
So I had a similar idea but just to improve the realism of the doll's passive motion during playtime with no electronics. The doll's are relatively stiff during playtime I'm assuming because their skeletons are stainless steel with hinged joints. How difficult do you think it would be to just incorporate a spring at each of the main joints? I have a traditional animation background, and in animation, there is a concept called "overlapping action." This is what is missing in rigid doll motion, except for the boobs because they are flexible. I believe springs would add this overlapping action when they're absorbing oscillating force during play. Here's a simple example of the animated motion concept: https://www.youtube.com/watch?v=4OxphYV8W3E

Springs could very well add realism to movement but I'm not sure how the tpe or silicone would react to something that expands and contracts like a mechanical spring. It's very possible the spring could tear either material unless it's encased in a sleeve . It's definitely an idea worth pursuing. On top of artificial muscle, I'm also working on a easier way to give dolls facial expresssion until the artificial muscle can be simplified and worked out...I don't care for servos much as I can stand the whine and mechanical sound of them.

onelove · Post by **onelove** » Mon Mar 27, 2023 8:14 pm

I wish you all the best! May God help you with your endevours!
This is something i've been thinking about too but i dont even know where to start. Like you said, we would need some new soft materials that contract or expand when electricity is passed through them. It would be amazing if each muscle could be controlled by a small computer like RaspberryPi. You could program your doll to do anything: smile, talk, gaze, walk, fuck, hug, kiss...

Technician · Post by **Technician** » Tue Mar 28, 2023 2:19 pm

I've been trying to make muscles that are essentially a series of 3D printed plungers to form a bellows, and I do have a 3d printed valve of sorts I designed that uses cheap MG90s servos with a PCA9685 servo controller that should be able to "feather" movements, not to mention a completed version would have skin in the form of Silicone or TPE that's elastic so that should dampen the harshness of movements further.
So far I've had a couple of fingers that work, but they aren't efficient enough for what I want, they don't need to be very strong because my application isn't about loading freight onto trucks, so I can sacrifice strength in favor of lower pressure.
Have to figure, a car tire with 10 - 15 psi may be low but it's still holding 1/4 of a 3,600LB car off the ground so I'm trying to stay 15 - 20LBS of pressure to hold a 60 - 70LB doll on her knees, sitting up, and such. Thomas Edison once said he knew 10,000 ways not to make a light bulb, so far I know about 60 ways not to make a 3d printed muscle.
A team at Harvard made tentacles which are simply more elastic on one side than the other so they curl with air pressure, I'm trying to avoid elastic actuation for various reasons like cost effectiveness for one, but it's a really simple and cool idea they had.

https://seas.harvard.edu/news/2022/10/t ... le-objects

Witchetty · Post by **Witchetty** » Sat Apr 22, 2023 8:17 am

Same, ever since I learned about transhumanism I've been wanting to develop it and it's something I think about *a lot*. Aside from the reactive material - there is one I looked into called ferrofluid and electrorheological fluids, (I was obsessed with these until life got in the way of studies). They're liquids which can be manipulated and even turned completely solid when magnetic fields or electrical current is added, respectively.

Something I would suggest first is studying anatomy closely - then tie it in with your electronics experience. I'm doing it in the opposite order.. Just now getting into engineering.

as of yet I'm not sure which one is harder.
What might be of use, at least for more accurate muscle movement visually, would be a structure made of many small strands/strings that can slide with little to no friction against each other, as muscles do. It would be a challenge to make this work, but it could be worth it - it could make limbs feel significantly more realistic. Even better if they're stretchy and return to a resting position.

Definitely a lot to think about.

Post by **The Doll Man** » Sat Apr 22, 2023 8:48 am

Witchetty wrote: ↑Sat Apr 22, 2023 8:17 am Same, ever since I learned about transhumanism....

Welcome To Forum!

pmaster · Post by **pmaster** » Sat Apr 22, 2023 9:41 am

You can use wound fishing line apparently to create artificial muscles.
https://www.instructables.com/DIY-artificial-muscle/

Or if you want pre built electroactive take a look here.
https://www.artimusrobotics.com/products

arisemyminions · Post by **arisemyminions** » Thu May 11, 2023 10:00 am

Springs might be a little too stiff, but I wonder if something like very light internal resistance bands could help recreate some of that "muscle" feeling. Depending on the position there can be opposing tension between difference parts of an arm or leg, something strong enough on either side to add a little bit of a rubber band effect without being strong enough to move the skeleton out of place or lose poses.

King Solo · Post by **King Solo** » Thu May 11, 2023 11:49 am

arisemyminions wrote: ↑Thu May 11, 2023 10:00 am Springs might be a little too stiff, but I wonder if something like very light internal resistance bands could help recreate some of that "muscle" feeling. Depending on the position there can be opposing tension between difference parts of an arm or leg, something strong enough on either side to add a little bit of a rubber band effect without being strong enough to move the skeleton out of place or lose poses.

Yeah, the Ruby13 had something similar to that in the design of their skeleton. It's just a shame as to what happened to that company after the owner passed. Because the skeleton that they were using made that doll move in such a sexually responsive way. That unfortunately still hasn't been remotely reproduced by any doll manufacturers, to this very day.

NikolaLee · Post by **NikolaLee** » Tue Jun 20, 2023 10:47 pm

Great topic! I am fascinated with the innovation and tech enhancing our dolls realizism to the next level. Artificial muscles, layer of skin, anything to make posing look and feel natural is a great enhancement. It's the main factor/reason for me to add another beauty to my collection.

I'm sure the actual technology is already out there. Well maybe not the artificial muscles. But doll manufacturers can add these existing tech/innovations to their existing dolls.
But to be realistic, the cost would be too high and demand too low to be profitable.

Sorry for getting off topic.
But here's a thought.
I'd like to see a merger of a robotics company with a doll manufacturer.
For example:
Tesla-Zelex Bot, Boston Iron Tech Dynamics, Tesla-Gynoid Model 10.