Lateral and Transverse Movable Mass Impacts on Bandwidth of Kinetic Energy Harvesters

Abstract

Abstract Vibrational energy harvesters have significant potential to replace batteries to create self-sustaining systems able to harvest energy from the ambient environment. However, currently high Q-factor or low bandwidth is a major challenge that needs to be resolved, as typical linear MEMS energy harvesters have a frequency bandwidth of about 1–3 Hz. Various methods to increase the bandwidth have been investigated but, they often result in a significant reduction of power. This study investigates a new method of increasing bandwidth without significantly reducing power. The study experimentally investigates the use of lateral and vertical moving masses to solve this problem. Vertical movable masses create non-linear dynamics to increase the bandwidth but also results in lowering the power, whereas lateral moving masses have a slight increase in bandwidth but almost no reduction in power. By combining these methods, it was demonstrated that a device can be created that increases bandwidth by > 1000% with only a 54% reduction in peak power. This paper demonstrates a proof of concept at the macro-scale and provides researchers with valuable information to allow them to tune the power and bandwidths to meet their application specifications.