直线电机驱动的H型气浮导轨运动平台

H-type air-bearing motion stage driven by linear motors

建立了双边直线电机驱动的H型气浮精密定位平台,对该精密定位系统的气浮导轨设计方法和双边直线电机同步运动控制等关键技术进行了研究。利用有限元法设计了气浮导轨,分析了气膜压力场的分布情况,采用预加载技术提高气浮导轨的承载能力和刚度等性能。静态特性实验表明,开发的定位平台气浮导轨具有较高的承载能力和刚度,X、Y导轨的竖直方向静刚度为276.9 N/μm和333.3 N/μm。设计了基于同步速度偏差的改进型并联结构同步控制器,采用模糊控制实现PID参数的自适应在线整定。运动实验表明,改进的控制器具有较高的同步控制精度,速度同步精度比一般同步控制提高了3倍多,适合于具有强机械耦合的多电机同步运动控制。H型直线电机气浮定位平台具有承载能力强、精度高的优点,可以用于光刻机和光学检测等精密工程领域。

An H-type air bearing precise positioning stage driven by dual linear motors is established. Some key techniques, including design method of air bearing slider and synchronic-motion control of dual linear motors, are studied. The air-bearing sliders are designed by finite element method, and the pressure field distribution of gas film in the bearing gap is analyzed. Preload technologies are adopted to improve air bearing＇s static performance. The static experimental results show that the preload sliders developed by finite element method have high load capability and stiffness. The static stiffness in the vertical direction of X-slider is 276.9 N/μm and the Y-slider is 333.3 N/μm. The improved parallel structure synchronous controller based on velocity synchro-error is designed, which adaptively tunes the PID parameters on-line by the fuzzy controllers. The motion experimental results show that the improved synchronous controller has high synchronous precision, the velocity synchronous preci- sion is higher three times than the common parallel control, and will be suitable for multi-motor synchronization control with strong mechanical coupling. The H-type air bearing positioning stage driven by linear motors has high load capability and high precision, and can be used in precision engineering area such as photoetching machine and optical inspecting equipments.