Tricky project - Machiko cannon

Hello all. We are currently working on a Machiko costume, based on the HotToys figure. One of the ideas is to connect the helmet to the cannon, so the cannon moves when I move my head. It can be done, I just need to know how. We have a basic understanding of electronics and circuits, and the skills to assemble them. If doing this requires programming, well... we are in trouble Anyway, my idea is that this can be made with a motion sensor in the helmet, connected to some kind of servo-thingie (sorry, my technical vocabulary sucks), somewhat like the ones used in RC airplanes. Please tell me if I am wrong here. If anyone has any ideas, please share them. I am going through with the costume, though. I really liked it, and if I can get the cannon working, that's great, if not, well, a simple up-and-down mechanism also ends up looking good.
Thank you all in advance
Cheers