Sweeping piezoelectric patch vibration absorbers

This paper presents a simulation study concerning the low-mid frequencies control of flexural vibration in a lightly damped thin plate, equipped with five time-varying shunted vibration absorbers. The panel is excited by a rain-on-the-roof broad frequency band stationary disturbance. The absorbers are composed of piezoelectric patches connected to time-varying RL shunt circuits. Continuous, sweeping, variations over time of the shunts are implemented in such a way as to swing the resonance frequency and damping factor of the absorbers within certain ranges and in this way to reduce the resonant response of multiple flexural modes of the hosting plate. A single patch absorber implementing the sweeping shunt is first presented and its performance is compared to that of a classical patch absorber with time-invariant RL shunt. The same analysis is conducted for a multiple patch system using five shunted absorbers. The control performance is assessed considering the spectrum of the total flexural kinetic energy of the system in the 20 Hz to 1000 Hz frequency band. The study shows that the configuration with five time-varying shunted piezoelectric patches reduces the resonance peaks of the kinetic energy spectrum by 5 to 15 dB.