Like the legs, the shoulders will initially be made from aluminum and later 3D printed to allow the bot to be reproduced easily. For the shoulders, I want two degrees of freedom so the shoulder will have two gear head motors, one for vertical motion and one for horizontal motion and two feedback potentiometers. I’m also shooting for 270 degrees of motion from each joint, horizontal, vertical and also the knee joints. This should allow a great range of motion and should allow the bot to walk right side up or upside down. Once the prototype is built, it is going to be fun to see exactly what the different ranges of motion will be.