Research On Two-dimensional Inertial Piezoelectric Actuator Driven By Piezoelectric Stack

With the rapid development of science and technology, MEMS is concerned by many domestic and foreign researchers. As a kind of precise actuators, Inertial piezoelectric precision actuators are driven by the rapid deformation of piezoelectric elements, which have many characteristics such as compact configuration, good response characteristic, non-electromagnetism interfere, convenient control and so on, and are applied to high resolution, large stroke occasion. Nowadays, inertial piezoelectric precision actuators are playing a very important role in the domain of precise actuation.Base on the theory of inertial impact in this paper, an inertial piezoelectric actuator with separate structures which can move direct and circumgyrate by the way of changing the stress between the driving mechanism and the contact surface is put forward. What will be the main work during the process of reseaching are analyzing the moving principle, designing and manufacturing the actuator and testing the performance of the actuator, etc.The main content is as follows:1. The research and development of piezoelectric actuators In recent years, people in various fields began to reform and innovate the technology, thus many new advanced technology appeared. In the field of micro-machine, as with many advantages such as good linearity, convenient control, response characteristic, non-electromagnetism interfere and non-yawp, etc, piezoelectric actuators are usually applied to precise orientation, ultra precise maching, optics adjusting and biomedicine.There are three kinds of piezoelectric actuators, which are step-by-step piezoelectric actuators, directly driven piezoelectric actuators and inertial piezoelectric actuators. Inertial piezoelectric actuators are devided into two kinds, which are inertial impactive style and inertial frictional style. It is the main content of this chapter that introducing the development of piezoelectric actuators.2. Analyzing the performance of the piezoelectric stackThe main content of this chapter is introducing the theory of piezoelectricity and comprehending some characteristics of piezoelectric elements such as electromechanically coupled coefficients, dielectric loss factor, electrical quality factor, mechanical loss factor and mechanical quality factor, etc. Establish a dynamic model and a simulink simulation model which are based on the knowledge of the piezoelectricity and the dynamics. The dynamic model of actuator is a spring-damping second order vibration system. Analyze the response of the actuator which is under the effect of sine signal. The simulation results provide theoretical foundation to master the dynamic characteristics of piezoelectric stack and to improve the performance.3. The structural design and simulation analysis on the piezoelectric actuatorPut forward the project by analyzing the motional theory of piezoelectric actuator and design the actuator with separate structures. Because of basing the theory of changing the friction between driving mechanism and the contact surface, the research on friction is important to design the actuator. The dynamic model of the actuator is established in this chapter. Furthermore, in order to analyze the effect of friction on the actuator, the simulation model of the actuator based on the Karnopp frictional model is also established. Some performances simulated by simulink tool: the relationship between the step and the voltage of signal; the relationship between the velocity and the voltage of signal and the relationship between the step and the stress.4. The experimental study on the inertial piezoelctric actuatorManufacture the specimen of the actuator according to the parameters of simulation. The performances of the piezoelectric actuator which will be tested: the relationship between the velocity and the voltage, frequency of the signal; the relationship between the step and the voltage, frequency of the signal; the relationship between the step, velocity and the weight of the block. Analyze the problem that appeared during the experiments.5. Research on the closed-loop control systemIn order to improve performances of the actuator, a set of feedback control system has been designed. Design a Fuzzy PID control system which is based on LabVIEW. Introduce the experiment system, and edit data collecting program, fuzzy control program and the main program with LabVIEW.6. ConclusionThis chapter is mainly about the conclusion obtained in this paper. Give some advice and prospects for future research.