Generation characteristics of piezoelectric vibrator driven by groove cam: Simulation and experimental analysis

Abstract

In this paper, a structure for a piezoelectric beam vibrator driven by a groove cam is analysed. The vibrator takes the simplified form of a piezoelectric beam model, where one end of the beam is clamped and the other end is simply supported, and is thus named the clamped/simply supported piezoelectric beam model (CSPBM). Mathematical models of the damped forced vibration and electromechanical energy conversion processes of the CSPBM are established based on the harmonic displacement excitation of the simply supported end. Factors that affect the energy generated by the CSPBM are analyzed theoretically and are simulated separately using both the MATLAB software and ANSYS software. Theoretical analysis results indicate that there is an optimal value of the ratio of the base plate thickness to the beam thickness (α) at which the energy generated by the CSPBM is maximum. In addition, the optimal α value of a unimorph beam is about 0.3 and is irrelevant to the material parameters of the beam. The voltage and energy generated by the CSPBM are measured on an experimental bench and the results show that the maximum generated voltage increases with increasing the first natural frequency when the α value of piezoelectric beam and the amplitude of displacement excitation are constant. In addition, the theoretical results of the generated voltage are coincident with experimental results, which confirms the validity of the theoretical model. The vibrator driven by a groove cam provides a practical form of the piezoelectric beam excited by the displacement.