Using the motion of your leg to create electricity, it extracts energy from the swinging motion of the knee, the same way some hybrid cars and trains can create electricity while braking, say researchers. During tests, up to 54W of power was generated – enough to light an incandescent 40W lamp, and more than enough to power your mobile phone or iPod.

They also say the brace has the potential to be used in prosthetic limbs and pacemakers, or on the average joe like me and you – when we don't have access to electricity. Like when climbing Mount Everest, for example.

A commercial version of the brace is expected to be ready in about 5 years. And why the knee? The researchers determined the knee to be the productive part of the body for generating electricity.

One of the inventors Max Donelan from Canada said, “The knee is probably the best place. During walking, you dissipate energy in various places, when your foot hits the ground, for example. You have to make up for this by performing work with your muscles.”

While we are not too sure about the looks of such a "brace" on our knee while walking out and about, we love that it can power our devices while we are on the go. TreeHuggers have been talking recently about ways to green the gym. This bionic knee brace seems like a good start.

And if this device ever comes to market, do not power your iPod while you are listening to music and simultaneously dancing across the street. We know it sounds fun – dancing and creating power at the same time, just keep the music part for the disco. See related::Dangers of iPods on Cyclists and Pedestrians, ::Treadmills Suck

::Times Online

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