New Bionic Leg Thinks and Moves Like a Real Limb

Traditional, un-powered prosthetics aren't exactly pinnacles of design evolution—they're heavy, cumbersome, and don't move like a living limbs. This new leg—using recent advances in motor, processing, and sensor technology—walks and reacts just like a real leg. Here's how:

Developed at the Vanderbilt University the leg uses both a powered knee and powered ankle, operating in unison to lift the foot and swing it forward naturally, eliminating the dragging-gait seen with traditional prosthetics. It also uses an advanced sensor suite to monitor the leg's motion, momentum and position, feeding that data into processors that predict the user's intention and react accordingly. The leg's anti-stumble routine, for example, monitors the leg's position and momentum. If it senses the user stumbling, the leg automatically lifts the foot clear of the obstacle before replanting in on the ground.

The leg itself weighs a scant nine pounds, requires 30-40% less energy input from the users and, with the help of new battery technology, run for three days with normal use.

"With our latest model, we have validated our hypothesis that the right technology was available to make a lower-limb prosthetic with powered knee and ankle joints," said Vanderbilt Center for Intelligent Mechatronics director, Michael Goldfarb in a press release. "Our device illustrates the progress we are making at integrating man and machine."

Combined with Mark Stark's prosthetic hand, Dean Kamen's Prosthetic ‘Luke' Arm, Matthew James Mercedes-branded i-LIMB Pulse, or Oscar "'Poor Little Tink Tink" Pistorius' carbon fiber sprinting legs, that integration is getting closer by the minute.

[Vanderbilt University via PhysOrg]