Active control of circular plate vibration by using piezoceramic actuators

An active vibration control system is proposed for suppressing small amplitude harmonic vibrations of a thin circular plate. This system integrates control algorithms, intelligent materials hardware and software technologies. The mathematical model of the physical system is based upon the geometry and properties of an experimantal set-up consisting of a hard-walled cylinder with a thin aluminium plate at the end. Primary excitation is provided by a low frequency loudspeaker installed centrally at the bottom of the cylinder. The vibrations of the plate are measured by the application of strain sensors. Intelligent materials such as 2-layer piezo disk elements (PZT) are used as the actuator. For the considered system, the OE (Output Error) method of discrete-time model identyfication for real-time active vibration control has been applied. On the basis of this model, the control algorithm based on pole-placement method has been developed. The obtained results show that the designed structure of a closed-loop system provides substantial vibration suppression.