FPGA-based motion controller with real-time look-ahead function

Abstract

This study proposes a field programmable gate array(FPBA)-based motion controller with real-time look-ahead function for computer numerical control(CNC) machines to achieve the purpose of high-speed and high-accuracy motion control. The proposed motion controller under PC-FPGA architecture uses a two-stage interpolation scheme to reduce the computational burden of non-uniform rational B-spline(NURBS) interpolation and look-ahead algorithms via parallel processing architecture, as compared to a single PC or DSP system. The PC performs look-ahead algorithms and first-stage interpolation, the FPGA receives the command from the PC and performs second-stage interpolation and servo control algorithm. Numerical simulations and experimental tests using an X-Y table indicate that the high-level integration implemented on the PC-FPGA architecture can improve the computing performance for NURBS interpolation via parallel computing, and enhance the tracking performance via look-ahead function and two-stage interpolation method.