Shoe embedded air pump type piezoelectric power harvester

Conventional shoe embedded PZT (Lead Zirconate Titanate) power harvesters have the problem of low reliability and short life time due to the fragility of the PZT material for bending and the high stepping force which directly acts on the PZT-metal structure. In this thesis, a novel shoe embedded PZT power harvester is presented, which is able to solve the problem of low reliability and short lifetime associated with conventional designs. This harvester uses an air pump to squeeze the air into a fixed chamber to deform a PZT diaphragm to generate electricity. Thus the high stepping force is directly taken by the housing of the harvester instead ofthe PZT material. A power of 1.12 mW is generated at a speed of 4 mph on a treadmill. The stepping force acting on the harvester is also measured, which indicates the power harvester can survive a very high stepping force.