Technique Research Of Adaptive Vibration Isolation For Vehicle Electronic Equipment By Piezoelectric Materials

This thesis focuses on the technique research of adaptive vibration-isolation for vehicle electronic equipment by piezoelectric materials.The piezoelectric materials have been widely used in the field of structural active vibration control as a new type of smart materials because of their excellent mechanical-electrical coupling characteristics. In this paper, the vibration of vehicle electronic equipment is considered as the vibration of cantilever beam, the vibration system of piezoelectric cantilever beam is studied. By the piezoelectric material's positive piezoelectric effect and negative piezoelectric effect, this paper analyses the interaction between PZT film and a vibration system of piezoelectric cantilever beam, the dynamical model and finite element model are established with regard to a pair of PZT sensor/actuator. The method of active vibration control is studied, and the equipment of adaptive isolation is designed. On the above, the experimental platform for a piezoelectric cantilever beam is set up, and the theoretical analysis has been verified by experiments. The main contents of this paper are described as follows:(1) By consulting domestic and international document, recent states of the application of active vibration control technology and present states of the research of piezoelectric materials in vibration control of structures is summarized.(2) The performance of piezoelectric materials is analysed. By researching the vibration characters of cantilever beam, PZT is selected as sensor and actuator.(3) The vibration of vehicle electronic equipment is considered as the vibration of cantilever beam. The basic theory of cantilever beam is analysed, and the basic equations of piezoelectric cantilever beam are derived.(4) The method of active vibration control is analysed, the method of PD is selected to control the vibration of cantilever beam, and the procedures is designed by LabVIEW.(5) By quadrilateral piezoelectric coupling element and two-dimensional solid element, the finite element model of system is set up, and the FEM equations of system is derived. By employing ANSYS, the structural static force and modal analysis about piezoelectric cantilever beam is performed.(6) The experimental platform for the adaptive vibration-isolation of piezoelectric cantilever beam is set up, the experiment of the vibration-isolation system is carried through. Good result is obtained in the piezoelectric beam experiment.