Professor Michael Goldfarb and his team are on the seventh iteration of a limb that combines a low weight (9lbs / 4 kg) aluminum alloy construction with embedded processors and powerful motorized knee and ankle joints. A rechargeable battery provides enough power for three days or 8 miles (14 km). A wide array of sensors monitor the leg's position and movement and the on-board software tries to anticipate the wearer's needs when sitting, standing, walking etc. A "stumble" routine for instance will try to lift the leg high to clear the obstacle and then plant it for stability. This anticipation means the leg operates much more like a real limb which allows the wearer to walk with a normal gait, even up and down stairs or across uneven terrain.
Source: gizmag.comAdded: 25 October 2011