高速高精度叠层直线运动控制系统

CONTROL SYSTEM FOR HIGH-SPEED AND ULTRA-PRECISION LINEAR MOTION BY DUAL STAGE

在分析粗精动控制系统的耦合及轨迹分配等问题的基础上,介绍叠层试验台高速高精度直线运动的实现: 采用永磁直线交流电动机驱动粗动台,粗动台行程大但带宽较低;音圈电动机驱动精动台,精动台带宽高但行程较小。用绝对空间闭环方式实现试验台的粗精运动控制,这种方法可以忽略粗动台对精动台的惯性力扰动,精动台直接跟踪给定轨迹,粗动台跟踪精动台的运动轨迹防止精动台发生运动饱和。试验结果表明,精动台显著提高了系统的定位和跟踪精度,该控制方法使叠层试验台的高速高精度运动得以方便实现。

On the basis of analysis for coupling and trajectory assignation of a coarse-fine control system the implementation of a dual stage system for high-speed and ultra-precision linear motion is presented. A permanent-magnet linear synchronous motor drives the coarse stage, which has large workspaee with low bandwidth. A voice coil motor drives the fine stage, which has high bandwidth with a small stroke. Close-loop feedback in absolute space is used to realize the coarse-fine control for the dual stage. Inertial force acted on the fine stage can he ignored by using the control scheme. The fine stage tracks desired trajectory, and the coarse stage tracks motion trajectory of the free stage for preventing motion saturation of the fine stage. The experimental results show that the fine stage improves positioning and tracking precision of the control system effectively and this control scheme can realize high-speed and ultra-precision motion of the dual stage conveniently.