Engineering students at Rice University in Texas have built a knee brace that harvests energy during walking, deriving power from every bend of the knee. Currently the brace stores the harvested energy in a lithium-ion battery pack. But the idea is to eventually take the energy harvested from the knee movement and use it to directly power an artificial heart. It could also power other medical devices through wireless.
The project is part of a program sponsored by Cameron International, a giant energy company based in Houston. It's the third consecutive year that Rice engineering students have worked on the energy harvesting project sponsored by Cameron. You can see a video about the program here at phys.org. It's a triumph.
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