Assessment of a piezoelectric energy harvester for a sensor module

A torsion based shear mode energy harvester is used to power a wireless sensor module consisting of a microcontroller, a temperature sensor, an accelerometer and a wireless transmitter. A 10 cm³ energy harvester was used and was found to produce nearly 450 μW of maximum power through an optimal load resistance under 0.5 g_pk acceleration excitation at its resonant frequency. This harvester was then tested using a standard diode bridge rectifier which was assessed for its suitability in powering the wireless sensor module.