Electric muscle for a robot

[EXO-0826]

Project for creating electro-muscle fiber for robotic drives
The drive consists of a central spiral guide and external thin conductors as (muscles) as well as coils at the ends of the muscle, and is in a strong elastic casing.
Do you think how effective such a muscle will be and from which materials it is better to produce?

 

[Baluncore]

Welcome to PF.

We need a diagram and some idea of the materials you will use. I think you will need to better describe the basic mechanism that is being used to provide muscle tension.

Many people are dreaming of, and working on, artificial muscles. The first thing to do would be some research on what others have done.
Google: polymer artificial muscles

 

[EXO-0826]

Hi, Baluncore

Initially, I was going to use copper, or nylon with copper coating, but it is not durable material, so decided to ask on the forum
The mechanism is based on the repelling of conductors with the same charge, and consists of a long guide in the form of a spiral (the conductor thickness is about 1 or 1.5 millimeters) in the center of the fiber, and the thin conductors stretching along it (the conductor thickness is 0.2-0.5 millimeters), attached to it every 1-1.5 centimeters.
When the current is passed through the fiber, the conductors begin to repel, reducing in length and creating an effort.

 

[berkeman]

The mechanism is based on the repelling of conductors with the same charge

It doesn't seem like that will be very efficient or powerful. There is a reason that motors use magnetic forces and not electrostatic forces. What motivated you to try to use electrostatic forces?

 

[EXO-0826]

Hi, berkeman

Repelling conductors with the same charge(+ and +,- and - )
Is it electrostatic?
If that's the case, I'll change the construction.
This type of muscle proposed to use as considered interesting, and quite effective.

 

[berkeman]

Repelling conductors with the same charge(+ and +,- and - )
Is it electrostatic?

Yes.

This type of muscle proposed to use as considered interesting, and quite effective.

Maybe of some interest, but I don't think it will be efficient or effective. As I asked before, why do you think that motors use magnetic forces instead of electrostatic forces?

Have you done any searching on "electrostatic motor"?

 

[berkeman]

Have you done any searching on "electrostatic motor"?

For example, I found many good articles with a Google search on Why are electrostatic motors not used?

Like this:
https://ludois.wempec.wisc.edu/electric-machines/

Electrostatic Machines

Is it possible to build an electric machine that does not require copper windings, steel, or magnetic material? Could plastic, aluminum, or ceramics be used? The answer is yes. Electrostatic machines use coulomb forces that result from electric fields acting on charge to make torque, rather than magnetic fields acting on electric currents. Although dating as far back as Benjamin Franklin (~1750), Electrostatic machines are not commonly used today due to their low volumetric torque density compared to conventional magnetism-based electric machines. To produce more torque and transition to a competitive position, an electrostatic machine must possess a large rotor-stator surface area immersed in a dielectric medium to store electric charge under high potential. Our group uses dielectric liquids, 3D printed structures with high surface area, and medium voltage power electronics to develop high torque electrostatic machines for low speed direct drive applications.

 

[EXO-0826]

Thank you for the link, this is very interesting information
I realized why electrostatic engines don't use, but it was about their low power relative to volume, and these fibers occupy a relatively small space, and in the drive they can be placed very much, which partially solves the problem of large volume

By the way, what is your opinion about such an electric muscle construction:
The drive consists of several wires that are not connected, but one wire is twisted into the other, on the one hand the wire is fixed on the moving object, and when the wires are given the current they begin to attract and create an effort.
It's just a possible option

 

[Nik_2213]

IMHO, you have a potentially elegant system for leggy 'spiderlings' in eg micro-gravity', that would otherwise struggle to move more than itself...
What do you want to actuate ? Does it have to haul its own power supply ?? Given power / weight and size constraints, would bot motion be better effected / controlled by eg R/C servos, with a zoo of sizes and soft-ware support 'Off the Shelf', or related rotary / linear actuators ?? Geared mini-motors have huge advantage that they may 'hold position' without power.

 

[EXO-0826]

Thanks for the answer, Nik_2213
Initially, I wanted to use this drive for large robots (mecha), but given all the problems will need a different drive.
The idea was to remove most of the intermediate systems (cables, gears, etc.) and make a muscle-like structure, for the legs and hands of the robot
I agree, geared mini-motors hold their position without power, but this can be done by placing on the joint conditional leg blockers