Research On Piezoelectric Smart Structure Integrated With Sensor And Actuator

Piezoelectric smart structure(integrated with piezoelectric sensor and actuator) is a newstructure which consists of a piezoelectric core element, a precision machinery support, andan integrated controller. It has a compact and highly integrated structure, and needs noexternal sensors and actuators. The integral structure is simple, easy to install, and flexible toapply. Piezoelectric smart structure is applied in isolation system, and it can reduce or eveneliminate the environment vibration of the light precision equipment to improve the overallperformance of precision equipment.Appropriate metal materials are chosen based on demand analysis of passive vibrationisolation and piezoelectric smart plant. Peripheral precision mechanical structure is designedthrough theoretical calculation and finite element analysis, and its vertical stiffness is tested.The functional requirements of piezoelectric sensor and actuator are analyzed.Appropriate piezoelectric materials are chosen. And the structure and size of piezoelectricsmart plant are designed. Theoretical study of piezoelectric sensors is conducted, and theexperimental scheme is designed to calibrate its sensitivity.A modified Bouc-Wen model is proposed so as to improve the accuracy of model-basedcompensation control of piezoceramic actuators. The modified Bouc-Wen model is introducedby ameliorating shape control parameters to simulate the asymmetric hysteresis curve ofpiezoceramic actuator. The model parameters are identified by particle swarm optimizationalgorithm. Feedforward compensation control as well as feedforward plus PI feedback controlbased on the proposed model are carried out to investigate its effectiveness on improving thedisplacement output accuracy. The results indicate that, for the same control method, controlby using the modified model can achieve higher trajectory tracking accuracy.A single support system model is established, and the transfer function is derived. Anexperimental scheme is designed to test the frequency response curve of the structure. Theanalysis results of the single support system model are applied to determine the transferfunction of the mathematical model. Finally, related parameters of the transfer function aredetermined using trial and error method and particle swarm optimization algorithm.