Control Strategy And Experimental Research Of Micro-motion Platform Driven By Dual Piezoelectric Ceramics

Since piezoelectric ceramic actuator has the advantages of high precision and high resolution,it is widely used in micro-motion platform.But the positioning precision and quick response of micro-motion platform is reduced by hysteresis nonlinear intrinsic characteristics of piezoelectric ceramic actuator which even worse leading to system instability.Besides,control strategies has a direct impact on micro-motion platform.Through the control strategies hysteresis characteristics of piezoelectric ceramic is reduced and he dynamic response performance of the platform is improved.That research is based on micro-motion platform driven by dual-piezoelectric ceramic actuator.Since hysteresis characteristics,inverse hysteresis model is established and connected to hysteresis system to correct the control voltage and then compensate for hysteresis nonlinear.In order to further improve the positioning precision and quick response of micro-motion platform,using dual-drive control technology,micro-motion platform driven by dual-piezoelectric ceramic actuator is designed and control strategy is presented making platform move stability and the positioning precision be increased.This specific research contents are as follows:1.Based on the theory of hysteresis of piezoelectric ceramics and the expression of Prandtl-Ishlinskii improved Prandtl-Ishlinskii is proposed describing the asymmetric hysteresis curve of piezoelectric ceramic.Prandtl-Ishlinskii inverse model is built reducing hysteresis nonlinearity by feedforward control strategies.2.To further improvement of the control accuracy,being introducing dual drive control technology,micro-motion platform driven by dual piezoelectric ceramic is designed.According to input and output data of the experiment,mathematical model of platform is identified for dynamics analysis.3.Compound controlling strategy that consist of dual drive control strategy and feedforward control strategy using Prandtl-Ishlinskii inverse model.That strategy not only modify the hysteresis nonlinear by feedforward method but also compensate the error of positioning by feedback,which improve the positioning precision of platform.4.Experiment platform is constructed and control software is developed based on micro-motion platform driven by dual piezoelectric ceramic actuator.Through the experiment between control strategy of signal piezoelectric ceramics(FF+PID+ Dual PZT)and control strategy of dual piezoelectric ceramics(FF+PID+ Dual PZT),compound controlling strategy of dual piezoelectric ceramics is effective.