Active Cross Pre-Compensation Decoupling Control of X-Y Linear Motor Platform Based on Contour Error Analysis Model

Abstract

To improve the position accuracy of the X-Y linear motor motion platform, this paper derives a contour error analysis model (CEAM) and proposes an active cross pre-compensation decoupling controller (ACPDC). Three major factors affect the tracking performance of the X-Y motion platform are obtained from the derived CEAM: uniaxial-axis subsystem performance, dynamic compatibility between multiple axes, and disturbances. CEAM also shows that better contour control can be achieved by combining the unified modeling idea. Therefore, the ACPDC proposed in this paper integrates the inter-axis controller and single-axis subsystem by establishing a unified control law that combines active precompensation control with linear active disturbance rejection control. The theoretical analysis based on CEAM shows that ACPDC achieves improvements in the above three aspects. Finally, experimental results on an X-Y linear motor platform support the CEAM analysis that ACPDC has better contouring performance than other multi-axis controllers. Compared with these controllers, ACPDC has the best system robustness and uniaxial tracking performance.