Some people exercise by power walking. But what if walking could provide electrical power? Researchers in Canada have developed an electrical generator mounted on the knee that turns walks into watts.
The device, which in its current form looks a little like a simple knee brace with cyborg bling, harnesses power from part of the stride.
J. Maxwell Donelan, the creator of the device and a professor of kinesiology at Simon Fraser University in British Columbia, compared the device to the regenerative braking used to produce electricity for hybrid cars.
The generator does not capture the motion throughout the entire stride, since that would subject the user to a dragging feeling with each step. Instead, the gearwork disengages at the beginning of the step and re-engages as the leg swings back from a stride.
This means that the only drag occurs at the tail end of the stride, when muscles are actually working to slow the leg down. It does not detract from the energy required for moving forward, and in fact, by slowing down the leg at that stage of the stride, ends up relieving the muscles of some of the effort.