So i got this idea waay back when i was in highschool as a kind of electromagnetic analogue to a biological muscle. it is basically a long stack of thin electromagnets connected in parallel. . when current is applied gaps between electromagnets shrink thus providing contraction of the whole chain.
I am pretty sure it can work. It can't offer great contraction range (up to 50% i would guess) but it has potential to provide good speed and be compact so that multiple chains can be combined to form stong and fast linear actuators. The thing is, i never heard of this type of actuator being used. so what is the catch? is there a better alternative? is there a design flaw? too much heat generated making them unpractical?