Bionic Power

We've seen several designs for military exoskeletons that can boost soldier strength, but these leg braces from Canada's Bionic Power generate electricity on the go.

The PowerWalk system looks like an athletic knee brace and weighs about 1.7 pounds. The braces generate about 12 watts of electricity when the user walks at a normal pace; an hour's walk can apparently produce enough juice to recharge four cell phones.

That's especially handy for soldiers who have to carry up to 28 pounds of batteries on a 72-hour mission to power everything from flashlights to night vision goggles, according to Bionic Power.

While they've been under development for years, undergoing Canadian military testing in 2008, the PowerWalk braces are now the subject of three development contracts from Defence Research and Development Canada (DRDC), DARPA, and the U.S. Army.

The development work will focus on making the braces produce more power when going downhill, as well as reducing the size of their gearbox. Another possibility is storing some of the power generated to help soldiers hauling heavy loads.

And the cost?

"For a soldier's typical duty day, the PowerWalk M-Series would save $135 in batteries," Bionic Power says on its Web site. "Assuming 200 mission days per year, the cost savings add up to $27,000 per soldier per year."

The DRDC and the U.S. Army are expected to get refined PowerWalk braces next year, according to Defense News. Further tests are needed before manufacturing begins.

But won't robot soldiers be fighting all our wars by then?