Parasitic Power Harvesting in Shoes
Joe Paradiso, Jake Kendall, John Kymissis, Nate Shenck

Kludge Magnetic Generator onto shoe
Generate 0.25 W average power during walk
High power, but very obtrusive and fragile

Implant Piezoelectric elements in shoe soles to scavange energy during walking

No effect on gait; undetectable

Generates 20-80 mW peak powers (1-2 mW average) during brisk walk

Application: Wireless, Batteryless RFID Tag

  • Store charge over several footsteps
  • When capacitor full, discharge through:
    regulator, 12-bit encoder, 310 Mhz ASK transmitter
  • Transmits 12-bit digital RFID from shoe to vicinity every 3-5 steps
  • Enables smart building to track occupant location

In demo, one sneaker uses PZT (activates via pressure)
and the other uses PVDF (activates via bending)

No Need for any Battery!
All Power scavenged unbotrusively via walking

Parasitic Power Harvesting in Shoes John Kymisis, Clyde Kendall, Joseph Paradiso, and Neil Gershenfeld. To be presented at the Second IEEE International Conference on Wearable Computing (ISWC), October 1998.