Research On The Modal Design And Dynamic Characteristics Of Accelerometer Based On Sensitive Piezoelectric Materials

In the filed of detection system, sensor which belongs to the signal source is a very significant part. The study of sensor working mechanism, structural design and analysis is very important to the sensor manufacture. Based on a kind of accelerometer with piezoelectric materials, the sensor structural design and dynamic behaviour analysis are proceeded. Mainly, the following research contents are carried out in this dissertation:(1) The properties of sensitive materials, measurement principles and mechanical-electrical conversion principles are presented to analyze the mechanism of piezoelectric accelerometer. The qualitative analysis of frequency response characteristic of piezoelectric accelerometer is obtained based on the above principles.(2) Based on the piezoelectric effect and the vibration measurement principle of accelerometers a plane shear mode accelerometer which satisfying micro-machining conditions is designed.(3) On the basis of finite element theory with anisotropic materials characteristic, the dynamic analysis of the proposed piezoelectric accelerometer is investigated. The following contents are analyzed:modal calculation and modal matching analysis of sensor parts level and entire structural system, influence rules of main electrical parameters on sensor dynamic behavior.(4) Based on the structure and dynamic characteristic of piezoelectric accelerometer, the sensor system is simplified to SDOF base excitation model, and the kinematic equation is built. Through the simulation, the displacement-frequency responses of sensitive elements and system structure are presented. Combining output voltage-frequency response, the 10 characteristics of sensors are discussed.