Design space: Chair for all terrains Product: Leveraged Freedom Chair to be distributed through NGOs, hospitals and government agencies Design: Massachusetts Institute of Technology's Mobility Laboratory, Whirlwind Wheelchair International, the Association for the Physically Disabled of Kenya, and the Transitions Foundation of Guatemala Territory: Developing countries Some 70 per cent of people who need a wheelchair in developing countries live in rural areas (about 20m people), but conventional "push rim" wheelchairs do not travel easily over dirt roads, sand and mud. MIT Mobility Lab, which develops mobility aids for use in such regions, wanted to produce a wheelchair for both rough terrain and indoors. The Mobility Lab's students designed the Leveraged Freedom Chair to be operated by levers attached to the wheels" pivots. The user's hands push the two levers back and forth, which turns the wheels. By changing hand positions, the user can effectively change gears. Grasping near the end of the lever gives more leverage and propels the chair through mud or sand. Holding the levers lower down lets the wheels turn more quickly for swift travel on smoother surfaces. Indoors, the levers can be detached and stowed within the chair, allowing it to pass through most doorways. The chairs were tested for four months by 25 patients whose conventional wheelchairs had rendered them housebound. With the LFC, however, they were able to travel outside an average of 2.7km a day. This month, 100 LFCs are to be manfactured, with production capacity being built for 500 chairs a month by March.