Vibration Attenuation with Random Shunted Piezo Patches

Abstract

This work deals with passive reduction of structural vibration by means of random shunted piezoelectric patches. The systems analyzed, shunted structures, are com- posed of a mechanical system with piezoelectric elements shunted with LR circuits. They are electromechanical systems, i.e, coupled systems. Due to the coupling, energy can be transferred between the mechanical and electromagnetic parts of the system. Tuning the electromechanical parameters, it is possible to control the energy flow between the mechan- ical and electromagnetic parts in a way that the amplitude of vibration of the structure is attenuated over a range of excitation frequency. The idea is to use the shunted piezoelectric patches as dampers to the structure vibration. When the shunt is perfectly tuned to the resonance frequency to control, the vibration attenuation is optimal. However, the damping performance is subjected to uncertainties in the electromechanical parameters. The objec- tive of the paper is to quantify numerically the uncertainty in the attenuation performance of a cantilever beam with two piezoelectric patches and a resonant random “RL”shunt. The nominal values of the inductance and resistance are chosen in order to achieve maximum energy dissipation of the second mode of the cantilever beam.