Simulation study of active control of vibro-acoustic response by sound pressure feedback using modal pole assignment strategy

Abstract

The active control of vibro-acoustic response using sound pressure feedback is numerically studied. An output feedback approach based on sound pressure measurement for modal pole placement is proposed. The control performance is evaluated for the case of a baffled plate. The finite element method and the Rayleigh integral are used to model the structural vibration and sound radiation. Measures of observability of a mode in pressure outputs and the effect of time delay in the pressure feedback loop are discussed. Numerical results show that the chosen poles may be assigned to predetermined values by the active control with complex gains. It is also demonstrated that the pressure feedback control may make a very large reduction in acoustic radiation and structural vibration of the controlled modes in a wide frequency band when using constant gain at a lower frequency.