Multivariable feedback active structural acoustic control using adaptive piezoelectric sensoriactuators

An experimental implementation of a multivariable feedback active structura l acoustic control system is demonstrated on a piezostructure plate with pi nned boundary conditions. Four adaptive piezoelectric sensoriactuators prov ide an array of truly colocated actuator/sensor pairs to be used as control transducers. Radiation filters are developed based on the self- and mutual -radiation efficiencies of the structure and are included into the performa nce cost of an H-2 control law which minimizes total radiated sound power. In the cost function, control effort is balanced with reductions in radiate d sound power. A similarity transform which produces generalized velocity s tates that are required as inputs to the radiation filters is presented. Up to 15 dB of attenuation in radiated sound power was observed at the resona nt frequencies of the piezostructure. (C) 1999 Acoustical Society of Americ a. [S0001-4966(98)04812-7].