Transient analysis of a piezoelectric transducer beam focusing on impact parameters

The transient dynamic behaviour of impacted piezoelectric beams is studied from an analytical model. It is believed that the characteristics of the impact has great effect on the capacity to harvest energy from vibration. However, to the author's knowledge, present models do not involve the impact force. The purpose of this paper is to implement a fundamental formulation of the impact force into an existing dynamic model of a piezoelectric sandwich beam. To maximize the energy output from one specific beam configuration, a parametric study is conducted on impact parameters such as the speed, mass, rigidity and radius of the impactor. The impact force time signal is provided by numerically solving an analytical impact formulation. The system is then solved in the frequency domain using the assumed modes method, and the result is transformed into the time domain using a discrete inverse Fourier transform. The numerical and experimental results presented are in good agreement. The effects of the different parameters on energy harvesting are outlined. From these results, some design guidelines are provided to maximize the energy output.