Invented by Lawrence Rome of the University of Pennsylvania, US, and colleagues, this backpack converts the up-and-down motion of the hips that occurs while walking into electricity. With every step, a walker's hip rises by 5-7 cm and when carrying a heavy load it takes considerable work to lift a backpack through that distance. That mechanical work is converted into electricity as the backpack - mounted onto a frame via springs - oscillates to drive a gear on the frame that drives a small generator. The device could provide wearable renewable electricity for combat soldiers or disaster-relief workers working in remote areas.
展开▼
