Nonlinear MEMS Mechanism for Energy Harvesting from Mechanical Vibrations

摘要

The aim of this paper is the realization of a novel bistable U-shaped micro-electro-mechanical system to efficiently harvest energy from ambient vibrations. The classical approach is based on vibrating mechanical bodies (linear systems) that allow for collecting energy through the adoption of smart materials, magnetic or electrostatic solutions. The idea pursued in this work is to consider the device vibrations biased by external vibration sources and also a double well dynamic in order to increase the harvest performances. The switching mechanism is based on a U-shaped structure that oscillates around two stable states when the stimulus is large enough to exceed the potential barrier. The device has been designed and realized performing a custom technology (BESOI) based on 15 urn c-Si wafer. Numerical simulations and preliminary measurement campaign validate the nonlinear mechanism showing that the nonlinear system exhibits a behaviour suitable to harvest energy from ambient vibrations.