POWER SOURCE FOR MOBILITY AIDS

DESCRIPTION (provided by applicant): This NIH Phase II SBIR proposal is to develop field-testable prototypes of a high-energy-density power source for locomotion aids for the mobility-impaired. Paraplegics, many geriatrics and people with chronic lower-limb damage need a very lightweight, powered vehicle for local transport. Existing carts are massive (50-100 kg) which precludes their transport in automobiles, taxis and in luggage racks of bus, train and aircraft. Their major mass is their batteries. Powered wheelchairs also are fitted with massive batteries, which makes difficult their vehicle transport. The batteries used universally are lead-acid (sealed or gel) which have very poor energy density (per mass) compared to new energy sources now being innovated for military and emergency service. Today the best (and most expensive) rechargeable batteries (nickel metal hydride) store only 0.25 MJ/kg (70 W-hrs/kg) and the technology is static. Now DoD is developing short-term (Y2005), 5 MJ/kg (1400 W-hrs/kg) sources for soldier-borne power. We propose to develop a field-trial alpha-prototype of our unique energy source called DICE/GEN, which is especially constructed to serve the mobility impaired. It is a hybrid engine burning an innocuous fuel (ethanol), dry lubricated (no oil) and quiet. A small battery permits use in confined spaces for one hour, with up to 8 km range. Using the engine's electrical output for propulsion and to charge the battery, provides four more hours of travel up to 10.4 mph (75 km). The hybrid energy source, including fuel, weighs 4.5 kg permitting a folding, three-wheel, scooter with seat, weighing less than 12 kg. SII will work with Teftec Corporation, an independent electric wheelchair manufacturer to conduct field tests with alpha-prototype DICE/GEN to verify functional equivalence to conventional batteries. With an estimated 200,000 electric wheelchairs and scooters in the U.S. market, a light weight power source should reduce overall power requirements. Development of light-weight scooter with DICE/GEN power should further improve locomotion and transportation for the mobility impaired.