Need Help from you guys looking for a piston

[EvangelinevonWinter]

Im sorry if this is the wrong place to post this but im trying to find a place to get the most eyes on this issue.
Im trying to make a clip where a fembots arms has a removable panel with machinery inside. Obviously I want it to look realistic or else whats the point.
I started looking through google for element 3d and other sites and couldnt find one.
in a perfect world similar to lukes arm at the end of empire but thats a dream, but something with moving pistons or something similar.

its for a bionic woman clip and i need to have something for her arms and legs.

thank you for your help.

[The Thinker]

I don't know if this is exactly what you are looking for, but this is how a torn robot arm was done in the Swedish series Real Humans

https://www.youtube.com/watch?v=jsSwToFJ4-s

I can't help you with software though, no idea how this was done or what software to use, that being said the principle is relatively simple and is based on a mix of practical effects, "green screened" wounds and a simple raster picture of some servos.