Coordinated Adaptive Robust Contouring Controller Design for an Industrial Biaxial Precision Gantry

Abstract

To achieve excellent contouring performance, it is no longer possible to neglect dynamic coupling phenomena that occur during contouring controls, especially for a linear-motor-driven industrial biaxial precision gantry, which often moves at high speeds. In addition, effects of significant parametric uncertainties and uncertain nonlinearities need to be addressed carefully. In this paper, a discontinuous-projection-based adaptive robust controller that explicitly takes into account the dynamic coupling effect is developed for the high-performance contouring controls of linear-motor-driven high-speed/acceleration systems under various parametric uncertainties and uncertain nonlinearities. Theoretically, the resulting controllers achieve certain guaranteed transient performance and steady-state tracking accuracy. In addition, asymptotic output tracking is achieved under parametric uncertainties only. Comparative experimental results are obtained for a linear-motor-driven biaxial high-speed industrial gantry. The results verify the excellent contouring performance of the proposed schemes, even in the presence of parametric uncertainties and uncertain nonlinearities.