Advanced error sensing strategy for estimating amplitudes of the first few radiation modes of vibrating surface

Controlling the first few order acoustic radiation modes of a plate has been previously shown to reduce efficiently its total sound radiation at low frequency. In this paper, a new sensing strategy based on acoustic radiation modes for active structural acoustic control (ASAC) approach is proposed for the minimization of the acoustic radiation from a vibrating plate. Measuring a few points velocity on the vibrating surface and solving the underdetermined equations of the radiation mode expansion, the approximate values of amplitudes of the first N radiation modes can be obtained. Taking the above approximate amplitudes as the input signals of the controller, this forms an error sensing strategy based on radiation modes and corresponding active control strategy. The numerical simulations and experimental results are presented to show the feasibility of this error sensing strategy.