Research of direct-drive XY table contouring control based on NURBS interpolator

Feedrate fluctuation, chord errors, machining time, machine characteristics, and unreasonable planning may affect machining quality from some extent. Compared with conventional interpolation methods, parametric interpolation method perform better on reducing feedrate fluctuations, chord errors and it can save interpolation time simultaneously. Reasonable feedrate planning and dynamic motion control are also significant for precision improving. In this paper, NURBS interpolation is employed and feedrate is planned on basis of curve geometry and machine dynamic characters. Further more, a model-based disturbance attention control method is adopted in each single axis to reduce the disturbance and friction, besides, CCC combined with PEC control algorithm is applied in biaxial coordination control to improve the contour accuracy. Simulation results demonstrate that the proposed approach can significantly reduce the machining error of XY table.