Climbing up Willis Tower’s 103 floors is an impressive feat for anyone. But for Zac Vawter it was an even more impressive feat when he climbed one of the world’s tallest towers in a prosthetic leg that he controlled with his mind.
The “bionic leg” used by Vawter to climb Chicago’s tallest tower was developed by the Rehabilitation Institute of Chicago’s Center for Bionic Medicine. In 2005, the center unveiled a similar neural-controlled bionic arm. But the SkyRise Chicago climb — a fundraiser for the institute with 3,000 climbers — was the public’s first glimpse at the bionic leg.
“One of the biggest differences for me is being able to take stairs step-over-step like everyone else,” said Vawter. “With my standard prosthesis, I have to take every step with my good foot first and sort of lift or drag the prosthetic leg up. With the bionic leg, it’s simple. I take stairs like I used to, and can even take two at a time.”
RIC explains the science behind the bionic arm:
The procedure, pioneered at RIC, uses Targeted Muscle Reinnervation (TMR) to replant nerves that once went to an amputees amputated limb to new healthy muscle and tissue, allowing the neural information to be used to control a computerized prosthesis more naturally—the user simply thinks about what they want the arm to do. RIC’s “Bionic Arm” technology has been very successful in more than 50 patients worldwide, including several U.S. service members who lost limbs in combat.
With the bionic leg, the neural information controls a series of motors, belts, and chains that provide smooth, synchronized movement between the ankles and knees.
Vawter climbed Willis Tower in about 45 minutes. The Associate Press has this video from the climb: