高精度定位平台X-Y方向振动误差补偿

Vibration Error Compensation in X-Y Direction for High Precision Positioning Platform

为了减小定位平台在X,Y方向的振动误差,实现高精度定位,搭建了宏微结合精密定位系统,由高性能直线电机驱动,气体静压导轨支撑和导向的宏动平台实现系统的大行程微米级定位,并由安装在宏动平台上的压电陶瓷驱动的微动平台对系统进行定位精度补偿。建立了定位系统机电耦合振动模型,采用比例积分微分(proportion integral derivative,简称PID)控制与最小节拍响应控制相结合的策略控制宏动平台,采用前馈-PID控制驱动微动平台,通过电容式微位移传感器实时检测定位系统终端的位置输出信号作为微动台的输入信号,实现定位系统的闭环反馈控制,达到宏动平台的振动误差实时补偿的目的。实验结果显示,所设计的微动补偿平台具有良好的动态特性,定位系统具有良好的误差实时补偿效果,针对X,Y向的振动范围由补偿前的4和3.5μm,补偿后减小到1μm的范围内。结果表明,所研究的振动误差补偿方法可以有效减小定位系统的振动误差,提高系统的定位精度。

In order to reduce the vibration error of the positioning platform in the Xand Ydirection and realize the high precision positioning,first,a macro micro positioning system is built,it is driven by the high performance of the linear motor,gas static pressure guide rail support and guidance of the macro micro positioning platform with large stroke system,and the system positioning accuracy is compensated by the micro platform installed in the macro on the platform driven by piezoelectric ceramics.Then the electromechanical coupled vibration model of the positioning system is established,the macro dynamic platform is controlled by the combination of PID control and minimum beat response control,at the same time,adopting the feed forward-PID control to drive the micro platform.Furthermore,the position output signal of capacitive displacement sensor for real-time detection and location system for terminal as the input signal of micro displacement platform are used to achieve closed loop feedback control of positioning system,and ultimately achieve the macro moving system of vibration error of real-time compensation.Experimental results indicate that the micro compensating platform designed has good dynamic characteristics,real time error compensation effect is good for the positioning system.For the vibration range of Xand Yis 4μm and 3.5μm,after compensation is reduced to the range of 1μm.The results show that the vibration error compensation method in this paper can effectively reduce the positioning system to improve the positioning accuracy of the system.