Two Dimensional Bistable Vibration Energy Harvester

Abstract

AbstractIn this paper a new strategy for broadband, bi-directional, vibration energy harvester is presented. Often energy harvesting systems address unidirectional incoming energy, however this is a strong limitation when considering real applications; in fact it is very likely that incoming vibrations will not be aligned with the direction of motion of the harvester. Irregular vibrations along several orientations reduce the energy conversion and the harvester efficiency. A suitable harvester architecture for collecting energy from vibrations distributed along different directions is needed. Furthermore, often the ambient vibrations come with energy distributed over a wide spectrum of frequencies, with predominance of low frequency components. This work addresses both these issues by proposing a nonlinear bistable oscillator based on two-dimensional, magnetically-coupled, PZT-based beams able to extract energy from ambient vibrations with arbitrary directions. The basic idea will be presented together with the experimental prototype realized and the results obtained