In order to realize the high precision positioning of the system in the large stroke, a ultra-precision position stage based on macro-micro dual-drive is designed. The metallic bellows direct-drive stage is used to realize the system feed-in with a large stroke. The VCM-driv-en micro stage, mounted on the macro stage, realize the high precision positioning of the system and compensate the error which is generat-ed by macro stage. The double-grating detection is used to realize closed-loop control with position signal of bellows-driven macro stage and VCM-driven micro stage. The PID closed-loop of feed-forward in macro stage and neural network PID on micro stage is came up with a compound control strategy. The experimental results show that the repeatability error is 0.6um in the large stroke with 50mm.%为实现定位系统在大行程中高精度定位,设计了一种宏微双级驱动精密定位平台.采用金属波纹管直接驱动宏动平台,实现了系统大行程进给.安装在宏动平台上的音圈电机驱动微动平台,补偿宏动平台产生的误差并实现系统的高精度定位.采用双光栅检测方案,增量式光栅反馈宏动平台的位置信号,绝对式高精度光栅反馈微动平台的位置信号,实现二级精密驱动定位系统的全闭环控制设计.分别对宏动平台和微动平台建立数学模型,提出宏动平台带前馈的PID闭环控制和微动平台的神经网络PID复合控制方案.实验结果表明:该定位系统能满足大行程高精度的定位要求,在50mm的行程中重复定位精度能达到0.6μm.
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