Variable gain cross-coupled complementary sliding mode contouring control for direct drive XY table

For permanent magnet linear synchronous motor (PMLSM) direct drive XY table has the problems of uncertainties and biaxial coupling. On the basis of the establishment of PMLSM mathematical model and the analysis of system contouring error, a contouring control strategy combined complementary sliding mode control (CSMC) and variable gain cross-coupled controller (VGCCC) is proposed. CSMC was designed as a feedback controller. It can suppress the influence of uncertainties such as parameter variations, external disturbances and frictions of the system, and guarantee the strong robustness. Meanwhile, VGCCC was introduced to solve the coupling problems caused by mismatched parameters between the XY table. VGCCC can change the controller's compensation gain based on the real-time contour error obtained from the contour error estimated model. The contour error was allocated to each axis in a certain proportion to reduce the system contour error, and thus the precision contour machining was realized and the control precision required by the system was met. The experimental results show that this method makes direct drive XY table has strong robust performance and tracking performance, and further improves the contour machining accuracy of the system. © 2019, Harbin University of Science and Technology Publication. All right reserved.