Sound Transmission Control through Rectangular Plate by Using Piezoelectric Ceramics as Actuators and Sensors

This paper describes the active control of sound transmission through a clamped rectangular plate by using piezoelectric ceramics as actuators and sensors. Optimal use of the piezo electric ceramic actuator is investigated theoretically by using the transfer function from incident sound pressure to radiated sound pressure and the first order approximated damping ratio. By apply ing direct velocity feedback control by five pieces of the actuators, substantial reduction of peak level at eigen mode frequency is obtained below the frequency range of about 1500 Hz. The use of piezo electric ceramics as actuators and as sensors fails in the direct velocity feedback control experiment, but has potential for the direct position feedback control experiment.