Leg brace could prove a useful energy harvester
03 May 2015
Rice University engineering students have created an energy-generating knee brace that they hope might be useful for powering artificial hearts.
The device is a modified medical brace that generates power with every bend of the knee. The electricity (around 4W) is produced by a motor attached to the joint of the brace and this is used to charge a lithium-ion battery pack.
Houston company, Cameron International, brought the energy-harvesting project to Rice around two years ago, with initial studies focusing on a shoe-based generator.
The current team of students is the third to take on the project and they say they have pushed the technology significantly forward.
“We added a power conversion and storage system that was not present in the device at the beginning of this year,” says bioengineering major, Hutson Chilton.
“So we’re getting about the same power output, but we’re also able to convert it to direct current and store that into something useful.”
She is joined in this team by electrical engineering major, Taylor Vaughn, and three mechanical engineering majors, Adrian Bizzaro, Sean LaBaw and Chase Gensheimer.
The brace is comfortable enough to wear for long periods, says Gensheimer, who has done most of the road testing, including stretches on a treadmill.
“We had a previous design to build on, but we tried to make it lighter and easier to wear and move in.”
According to LaBaw, it was a challenge to reduce the mechanism and its casing to reasonable proportions while also reducing friction from the moving parts.
“We didn’t want somebody walking with a motor 6 inches off the knee and running into tables,” he adds.
The team expects a future version to supply energy wirelessly to medical devices.