压电陶瓷驱动微位移机构迟滞非线性改善方法研究

压电陶瓷驱动器在精密微位移系统中有着广泛的应用,但其固有的迟滞非线性严重影响系统的运动精度,使控制困难.通过数学建模方法建立压电陶瓷的迟滞曲线逆模型,并用此模型对压电陶瓷进行位移补偿,可以有效减小压电陶瓷迟滞非线性对系统精确控制的影响.提出一种用两个压电陶瓷协同驱动微动平台运动的微位移机构,通过基于迟滞逆模型的开环控制方法,对压电陶瓷位移进行误差补偿,可以实现微动平台运动与控制信号较好的线性对应关系.

Research on improving hysteresis of piezoelectric actuator used in micro-displacement mechanism

The piezoelectric actuators are used widely in the field of precise displacement system,but the inherent hysteresis and nonlinearity characteristics not only lower the moving accuracy of system but also make the control system more difficulty.To construct a hysteretic inverse model of piezoelectric actuator with mathematic modeling method and use this model to compensate the displacement error can reduce the hysteresis nonlinearity influence effectively in precise control system.A micro-displacement mechanism is proposed,which use two piezoelectric actuators work together to drive the micro displacement table moving.By using the control method under open-loop operation based on the inverse hysteretic model,the moving of micro-displacement mechanism and the control signal would have a better linear corresponding relationship with compensating the displacement error of piezoelectric.