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Appearance

A mechanical human-like hand that is attached to my right arm as an additional hand. It is made to the dimensions of my real right hand.
Cosmetic Cover

Cast in latex from my right hand. It was thought necessary to protect the sensors and to provide adequate friction for gripping. It was never permanently worn over the mechanism because for performance purposes only the visual motion and operation was important.
Materials

Aluminium, stainless steel, acrylic, latex electronics, electrodes, cables and battery pack.
Capabilities

Pinch-release, grasp-release, 290 degrees wrist rotation (clockwise and counter-clockwise), and a tactile feedback system for a sense of touch.
Control System

The motions of the hand are controlled by the electrical signals of the muscles (EMG), typically from the abdominal and leg muscles for independent movements of the three hands. Simply, signals from muscle contractions are picked up, pre-amplified, rectified and sent to the switching system.

Source : http://stelarc.org/?catID=20265