A MEMS Frequency Comb Energy Harvester

This paper reports on the observation of frequency comb phenomena in a mechanically driven piezoelectric MEMS structure configured as a vibration energy harvesting device. By exploring different mechanical driving conditions, both autoparametric resonance and frequency comb response is observed at relatively low drive amplitudes. The harvester response is characterized for both sinusoidal driving and under band-limited noise excitation. Under noisy excitation, the device exhibits frequency comb phenomena spanning multiple octaves. Significant gains in harvested energy are seen when the device is operated in the frequency comb operational mode as opposed to the case of operation in a more traditional resonant regime under the same drive amplitude. The large operational bandwidth and improved power response under noisy excitation offer promise of adapting this approach for practical application.