Leveraged Wheelchair

The Leveraged Wheelchair

Wheelchair users in developing countries often need chairs that work on rough roads. They can't afford the gear-shifting designs like Adaptive Sportsman's Renegade or Invacare's handcycles, however, that can cost from $2000 to $5000. Until now. Amos Winter founded MIT's Mobility Lab and has created a leveraged-chair design that gives varying degrees of power for off-road rolling and has a narrow wheelbase for comfort indoors. And it costs only $200.

Users effectively "switch gears" by moving their hands up or down on levers that rise from the side wheels for more leverage and more speed. The MIT team figures that, on pavement, their drivetrain gives 10 to 20 percent more speed than a traditional chair, and off-road, they say, it's unequaled. First-generation designs underwent field tests in Kenya, Uganda and Tanzania in 2009, and second-generation designs have been in the field in Guatemala since August.

Read more: 7 Medical Device Upgrades for Developing Countries - Popular Mechanics