Contour Controller Design for Direct Drive XY Table System Based on Friction Observer

Abstract

The contour accuracy of XY table directly driven by two permanent magnet linear synchronous motors is influenced by the nonlinear dynamics. To enhance the free-form contour following performance, real-time contour error algorithm was adopted. The friction observer can overcome the influences of the nonlinear dynamic of the single axis, the velocity mismatch between two axis is eliminated by the contour controller. The simulation results show that the designed controller makes the system of XY table have high contour machining precision and strong robustness.