Experiments on vibration suppression for a piezoelectric flexible cantilever plate using nonlinear controllers

This paper reports an investigation of the active vibration control of a piezoelectric flexible cantilever plate. The bending and torsional vibration of the flexible plate can be measured and actuated by distributed bonded piezoelectric sensors and actuators, after conducting optimal placement. To suppress the vibration, a kind of composite nonlinear controller is proposed and implemented. The control gain of the developed nonlinear control algorithm can be adjusted according to the measured vibration amplitude and the corresponding parameters. The advantage of the nonlinear controller is the ability to regulate the control value online to suppress both the larger and the smaller amplitude vibrations effectively, without allowing excessive saturation or insufficient phenomenon of the control effect. An experimental setup characterizing a thin, cantilever square plate bonded with piezoelectric patches was developed to verify the proposed controller. Experimental comparison studies were carried out for suppressing both the bending and torsional vibrations, and the control performance of the nonlinear controller is analyzed and discussed. The experimental results demonstrate that significant vibration suppression can be achieved by using the presented control schemes.