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ANDROID ATHLETE: Joules, the pedaling robot pictured with its designer, Carl Morgan [right], and his son, a former professional bicyclist, will generate 3 kilowatts of power—no match for Lance Armstrong, but enough to relieve the tandem bike’s helmsman of pedaling duties. Joules’s leg power comes from a pancake-style permanent magnet dc motor in its torso, which draws current from a pair of 48-volt, 15-ampere-hour lithium-ion batteries mounted to the bike’s frame. <