Dynamics of Energy Harvesting Mechanical System in the Vicinity of 1:1 Resonance

Abstract

Energy harvesting provides a useful way to power electronic devices without using batteries or electrical wiring. Energy harvesting can be defined as the conversion of environmental energy, such as mechanical, thermal, light energies into usable electrical energy. Conventional mechanical energy harvesting devices use a line harvester to generate electricity through vibrations or other mechanical motion. However, linear generators generate significant power in a narrow band around resonance, and the power is limited by the internal damping factor and the driving force at the resonant frequency. Such devices implementing a linear (resonant) generator cannot generate sufficient specific power. In present paper the mechanical system is considered which consists of two coupled oscillators (nonlinear absorber connected with primary mass) and a piezoelectric element attached. Two goals are pursued: the mitigation of the responses of the main mass and maximizing the amount of energy extracted from vibrations. The influence of nonlinear stiffness's component is discussed. It is shown that the piezoelectric element allows the effective energy harvesting and at the same has very limited influence on reducing the amplitude of oscillations of the main mass.