CHICAGO – The metal on Zac Vawter bionic leg gleamed as he climbed 103 floors of Chicago’s iconic Willis Tower, becoming the first person ever to complete the task wearing a mind-controlled prosthetic limb.
Vawter, who lost his right leg in a motorcycle accident, put the smart limb on public display for the first time during an annual stair-climbing charity event called SkyRise Chicago hosted by the Rehabilitation Institute of Chicago, where he is receiving treatment.
Everything went great, said Vawter at the event’s end. The prosthetic leg did its part, and I did my part.
The robotic leg is designed to respond to electrical impulses from muscles in his hamstring. When Vawter thought about climbing the stairs, the motors, belts and chains in his leg synchronized the movements of its ankle and knee.
The computerized prosthetic limb, like something one might see in a sci-fi film, weighs about 10 pounds and holds two motors.
We were testing the leg under extreme conditions, said Joanne Smith, the Rehabilitation Institute’s CEO. Very few patients who will use the leg in the future will be using it for this purpose. From that perspective, its performance was beyond measure. To prepare for his pioneering climb, Vawter said, he practiced on a small escalator at a gym, while researchers spent months adjusting the technical aspects of the leg to ensure that it would respond to his thoughts.
When Vawter goes home to Yelm, Wash., where he lives with his wife and two children, the experimental leg will stay behind in Chicago.
Researchers will continue to refine its steering. Taking it to the market is still years away.
We’ve come a long way, but we have a long way to go, said lead researcher Levi Hargrove of the institute’s Center for Bionic Medicine.
We need to make rock-solid devices, more than a research prototype.
The $8 million project is funded by the U.S. Department of Defense and involves Vanderbilt University, the Massachusetts Institute of Technology, the University of Rhode Island and the University of New Brunswick.
Nearly, 3,000 climbers participated in the annual charity event, called SkyRise Chicago. Participants climbed about 2,100 steps to the Willis Tower’s SkyDeck level to raise money for the institute’s rehabilitation care and research.
Sen. Mark Kirk, R-Ill., climbed 37 floors in his first public appearance since suffering a major stroke.
Kirk, 53, started walking from the 66th floor. He was met with hugs and cheers from family and friends at the end. The senator paced slowly through the crowd with the help of a cane, smiling but saying little to the media.
Kirk’s stroke in January severely limited movement on the left side of his body.