Thread: Electromagnet muscle

Hi i am a biology major and don't know a great deal about mechanics. So i am wondering if it is possible to use electromagnets to function as muscle. It would work i think by constructing a chain of electro magnets aligned so that the opposite poles face each other. The flexed state of this "muscle" would be when the magnets are all touching and the relaxed state would be when they are pulled apart, but still connected via elastic bands. My chief concern is whether the strength of the muscle would be greater than its weight and the weight of the power source and also whether sufficiently small but efficient magnets could even be constructed.

I have tried to verbally explain this to people i know, but usually i have to draw them a picture so if this doesn't make sense please let me know.

I suppose if one works hard enough it may work, but the biggest difficulty with magnetic force over a distance is the the fact that it's strength increases as distance declines. Nearly opposite of what you would want with muscle behavior. Magnetic motors work well because distances are constant so this difficulty goes away.

As far as magnetic strength goes, there are some very powerful ceramic and electro-magnets so power and efficiency won't be an issue at all. Still I would urge you to reconsider use of magnets over a variable distance.

You'll have problems with magnets as "muscle-like" elements since you will have other effects going on as well. And the total distance of travel will have to be very short.
On the other hand, you could use Nitinol, a Nickel-Titanium Alloy that changes length upon heating (or passing current through it). I beleive some people are using these fairly effectively to simulate muscle. Exact fit for an application would obviously have to be evaluated...

About six years ago I watched a video of a professor who is actually working on a rubber like material that can shrink or expand based on the current going through it.

I think the current required was very small, and the material was behaving like a flexible magnet as he explained. I am not sure if I still have the video clip, but once I have it I will post the link. Because it is quite similar to you idea.