the development work has been done on legs rather than replacements for lost arms and hands. Currently, officially approved designs for replacement arms.The device uses electrodes. they learn to control the 10 different movements the prosthetic arm can carry out.This prosthetic limb system can handle very rugged tools like a hand drill. The US Federal Drug Administration said the Deka Arm is designed for those who lost their arm at the shoulder, mid-upper arm or mid-lower arm. The Deka Research firm behind the Arm was founded by renowned engineer Dean Kamen.