基于RBF神经滑模的XY平台迭代交叉耦合控制

Iterative cross-coupled control for XY table based on RBF neural sliding mode

永磁同步直线电机(PMLSM)直接驱动XY平台的轮廓加工精度会受负载扰动、双轴参数不匹配以及周期性轮廓误差的影响.针对这一问题,采用RBF神经滑模与迭代交叉耦合控制相结合的方式对两轴运动进行协调控制.设计RBF神经滑模控制器用以削弱负载扰动对加工系统的影响.采用实时轮廓误差法估算出轮廓误差模型,并且将轮廓误差作为控制器的输入,设计迭代交叉耦合控制器用以削弱双轴参数不匹配和周期性轮廓误差对加工性能的影响,实现跟踪误差与轮廓误差的同时减小.仿真结果表明,所设计控制系统具有较强的鲁棒性和较高的轮廓精度.

The contour accuracy of XY table directly driven by permanent magnet linear synchronous motor （PMLSM） is influenced by the load disturbance, unmatched double axis parameters and periodic contour error. To solve the above-mentioned problem, the RBF neural sliding mode and iterative cross coupled control were combined to coordinate and control the double axis movement. The effect of load disturbance on the processing system was eliminated by the design of RBF neural sliding mode controller. The contour error model was estimated with the real-time contour error method. In addition, the contour error was regarded as the input of controller, and the influence of both unmatched double axis parameters and periodic contour error on the processing performance was weakened by the design of iterative cross-coupling controller （ICCC）. The simultaneous decrease of both tracking error and contour error was realized. The simulated results show that the designed control system has strong robustness and high contour precision.