Are there any inexpensive ways to make a material flex/contract when an electrical current is applied to it?

I'm working on a small-scale prototype toy and it would be nice to have the ability to apply a charge to a piece of material and have it flex or contract.

I kind of see it working a bit like a mechanical solenoid (and that is a possible option here although they would have to be tiny!) in that if the material looks like ____________ to begin with, when you apply a charge to it it becomes like __/\__ (excuse the poor ascii art!)

iceng5 years ago
It's called muscle wire ( Nitinol ) and  will amazingly shorten in length (with significant force) when electrically powered .
It is easy to use, and the thin strands of wire can lift thousands of times their own weight.

The contraction movement it produces may be applied to any task requiring physical movement,
allowing it to replace small motors or solenoids.
jeff-o5 years ago
If your toy has tiny legs where you can't locate a motor, maybe you could use wire actuators much like a bicycle brake cable. There would be a servo or actuator on the body itself, and just a thin cable running to the legs.
orksecurity5 years ago
Websearching "robot muscle" will probably find all the approaches people have tried for this.