Microstructured polymer for shoe power generation

We report on a shoe power generator based on a microstructured piezoelectric polymer transducer. The properties of the transducer match regular shoe filling and it is designed to harness energy from human walk without affecting the user's gait. The generated power is regulated with a self-powered dc/dc conversion circuit that achieves a high 65% efficiency for converting the high piezoelectrically generated voltage (130 V) to a low voltage (4 V) suitable for portable electronic devices. The entire power generation system is embedded into the shoe heel, has large power output (4 mW raw power, 2.6 mW regulated power per shoe) and is small, soft, lightweight, durable, and low cost.