Amputee Climbs 103 Stories Using Mind-Controlled Bionic Leg
A man with a mind-controlled bionic leg climbed to the top of Chicago’s famous Sears Willis Tower Sunday, part of a charity stair-climbing event. Zac Vawter, 31, lost his right leg in a motorcycle accident and is the first person to climb that many floors wearing a bionic limb.
Vawter lives in Yelm, Wash., with his wife and two children, but is a patient at the Rehabilitation Institute of Chicago, which sponsored the event. The leg is designed to respond to electrical pulses from muscles in his hamstring, according to the Associated Press. When he thinks about climbing a stair and begins to move his leg, the bionic leg synchronizes its movement to his muscles, ensuring a smooth gait. The leg weighs about 10 pounds and contains two motors, which drive a belt and chain system that swings the leg at the knee joint.