pic: Team 1178 Robot - Hand mechanism

Best picture I could find…Basic idea is push the piston out, push the “fingers” away from each other. This enables you to grab rings from the inside. And with the arm, it makes it very easy to pick them up off of the ground.

http://www.chiefdelphi.com/media/img/ea6/ea60f1f5ab86cbb8e354cb95cfecb312_m.jpg](http://www.chiefdelphi.com/media/photos/27452?)