Corrugated piezoelectric membranes for energy harvesting from aperiodic vibrations

In this work we report on non-resonant piezoelectric micro-energy-harvesters based on corrugated membranes made from aluminium nitride. These harvesters were designed to respond efficiently to aperiodic mechanical impact at low repetition rates. The piezogeneration efficiency of non-resonant systems was compared to conventional resonant devices like tensile stressed membranes and cantilevers. Special attention was paid to system properties that allow an operation at low frequencies in viscous media with high damping. Classical analytical modelling was employed to describe the corrugated microsystems with the aim to calculate the feasible energy outcome and to optimise electro-mechanical coupling.