Robust strategies for active vibration control of plate-like structures: Theory and experiment

Abstract

The theoretical modelling of the vibration of a plate-like active structure incorporating piezoelectric actuators is presented using the Rayleigh-Ritz method. The model was used to design multi-variable controllers (linear quadratic Gaussian and H_∞) for a cantilever plate with two piezoelectric actuators providing the controlled strain input to the plate with two non-collocated sensors providing the feedback signals. A technique for the optimal placement of piezoelectric actuators is developed using modal controllability and a genetic algorithm as the search engine. The proposed controllers were then implemented experimentally and the measured results compared favourably with those predicted from simulation studies. The results show that considerable disturbance attenuation can be achieved in lightly damped modes of the structure using optimal placement of piezoelectric actuators and multi-variable controllers.