基于PLC的大范围运动与高精度对准控制

针对掩模版传输过程中的大范围运动与高精度对准这两个关键问题，本文采用基于PLC的全闭环位置控制方法，设计了用于掩模版传输和对准的机械手控制系统。对于大范围运动，利用旋转编码器和光栅尺检测机械手的速度和位移，构成三闭环控制系统。对于高精度对准，利用四象限探测器检测掩模版位置与姿态偏差，构成四闭环控制系统。实验结果表明，利用本文控制系统，机械手在大范围传输和高精度对准时的速度和精度都可以满足生产要求。

Large range motion and high-precision alignment control based on PLC

Large range motion and high-precision alignment are two key problems in the transportation of mask. Aiming at the two problems, full closed-loop position control technique based on PLC is applied in this paper, and a set of manipulator control system is specially designed to transport and align mask-plate. When it's in large-scale movement, optical encoder and optical linear encoder are used to measure speed and displacement, so a closed-loop control system with three loops is composed. When it's in high-precision alignment, two four-quadrant detectors are used to measure position and pose deviation, and then a closed- loop control system with four loops is composed accordingly. Experiments show that the speed and precision when the manipulator is in large-scale transportation and high-precision alignment can meet the demands from manufacture