We like to joke about reinventing the wheel, but that's kind of what NASA engineer Salim Nasser has done -- he won a $20,000 innovation prize earlier this month for designing a wheelchair where the occupant can pull, thus avoiding repetitive stress injuries associated with pushing by using the (typically) stronger biceps and upper back muscles. The prototype uses a planetary gear system to drive the specially-designed wheels, which Nasser claims can be easily attached to existing wheelchair frames. There's no telling whether it'll see the mass market, but we wouldn't be surprised given the simplicity of the design, unlike some of the robotic models
we've seen. So... how's that for a new spin on things?