Piezoelectric Smart Structure Vibration Active Control Research Based On Subspace Identification Method

Piezoelectric materials can be embedded into structural materials and serve as both sensors and induced strain actuators in smart structure. It is an important part of research in smart materials and structures. Subspace identification method is a new time domain identification method, which has high computational speed, good robustness and high accuracy compared with classical methods. And more importantly, the Kalman Filter State used for controller design are estimated without the state space model. Matlab /xPCTarget platform is part of a family of software products that can be used to create real time systems. It provides new approaches for real time signal acquisition and control applications. Based on subspace identification method and Matlab /xPCTarget hardware platform, extensive theoretical and experiments were conducted on a piezoelectric composite cylinder. The following conclusions were drawn from: Firstly, experimental modeling was conducted on a piezoelectric cylinder based on subspace method and Matlab /xPCTarget real time data acquisition system. A state space model was obtained. Secondly, the LQG controller was developed based on subspace predictor derived from subspace identification method, and implemented with C programme. Finally, simulation was conducted based on Matlab /Simulink platform with the model and developed LQG controller. Also, a real time vibration active control experiment was carried out on the piezoelectric cylinder with the Matlab /xPCTarget hardware platform. Simulation and experiments on the system show that the selected modes can be suppressed effectively with the developed subspace-based LQG controller.