Active control of noise transmission through a plate using embedded self-sensing piezoelectric actuators

This paper presents a study of active noise isolation using an advanced composite board with built-in piezoelectric elements, which are used as both sensors and actuators. An identification system, which estimates the radiated sound from the voltage signals of the built-in piezoelectric elements in the smart board, was constructed based on Rayleigh's integral formula so that no external microphone is needed for noise control. A FIR filter was used as the controller and its coefficients were updated adaptively using the Filtered-X LMS algorithm to minimize the estimated value of the sound pressure. The technique of self-sensing actuators was also used to reduce the number of needed piezoelectric elements in the control. Experiments were performed and the results showed that the transmitted noise level was successfully reduced at several resonant peaks.