Simultaneous energy harvesting and vibration isolation via quasi-zero-stiffness support and radially distributed piezoelectric cantilever beams

Abstract

Most of the existing energy harvesters are based on vibration amplification, which inevitably causes large disturbing force transmitted to the base. In this paper, a novel energy harvesting device is proposed based on vibration localization, through which the force transmitted to the base can be significantly reduced, thereby achieving simultaneous energy harvesting and vibration isolation. The proposed device is composed of a quasi-zero-stiffness (QZS) support which can greatly lower the beginning frequency of vibration isolation region, and several radially distributed piezoelectric cantilever beams by which the vibrational energy is localized and harvested. The electromechanical coupled equations are formulated starting from the most elementary mechanical and electrical knowledge. The harmonic balance method is employed to analyze the dynamic response and output voltage, accompanied by the verification through numerical simulations. The non-dimensional output power and the force transmissibility are comprehensively studied with tuning key parameters to investigate the crucial characteristics of the proposed system. The results indicate that the energy harvesting region does lie in the vibration isolation region and the former can be flexibly tuned within the latter by altering the mechanical parameters of the piezoelectric cantilever beam; the peak power and energy harvesting bandwidth can also be tuned by altering the electrical parameters; most importantly, the enhancement of the energy harvesting performance can be achieved with almost no sacrifice of the vibration isolation performance.