Wearable computers are inconvenient if they must be battery powered. We want to use the energy expended in a person's natural motions to power wearable computers. Specifically, we want to harness the energy a person expends while walking to create parasitically powered shoe computers.
We are pursuing a vision of the future where the traditional wearable computers: the cellular phone, personal digital assistant (PDA), and pager are replaced by a self-powered shoe computer wirelessly using the watch as a display. The shoe is a perfect place for a wearable computer. There is a lot of wasted space in a shoe sole, the energy dissipated from walking can be used to power shoe computers, and PAN works best when one of its electrodes is near earth ground. A typical person dissipates tens of watts while walking. Harnessing one milliwatt of this power can run CMOS microprocessors. We hope to be able to someday harness 10 milliwatts of the available power.
Since a shoe undergoes various stresses and strains in the real world, our power source should have a modicum of moving parts. We are focusing on durable materials like poly(vinylidene diflouride) (PVDF) that create electrical energy from intra-molecular processes as well as traditional generators that generate power from macro-mechanical motion.
The ring oscillator runs off of approximately 10 microwatts of power. The scope trace shows the ring oscillator in action and we amplify the ring oscillator signal with a battery powered amplifier so we can actually hear the ring oscillator through a speaker.
Our immediate goals are to investigate other materials for power generation and to attempt to run micropower CMOS microcontrollers with our power shoe inserts.
John Kymissis, Babak
Nivi
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