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Robotic Stoker for Tandem Bicycles

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Built as a challenge from son to father as a way to ease uphill climbs, Joules is the product of just nine months of tinkering by retired electrical engineer Carl Morgan. Total cost: $3,000.

Morgan spent months modeling how to transform a motor’s spin into pedal-pushing legs. The motor inside Joules’s torso turns a series of linked belts and chains that transfer power from one area of the robot to the next. Each upper leg pivots at the hip, raising and lowering its knee and forcing the lower legs to turn the pedals. He also added “bones” (rods on the outside) for needed stiffness.

Featured on Popular Science’s You Built What? segment, this robotic tandem stoker is capable of pedaling at 2,400 RPM, but has been restricted to just 90 RPM for safety’s sake. It uses a 14 HP electric motor, and Morgan says Joules “is so powerful, it could probably climb a tree.”  Even at the restricted power output, he says it can probably top out around 30 MPH, but he isn’t ready to find out.

Read more on PopSci.com, and check out video after the break

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