Limiting tool path error generated by corner blending of CNC interpolator

Computer numerical control (CNC) part programs generated by computer-aided manufacturing software are frequently composed of numerous G01 blocks. CNC interpolator applies acceleration and deceleration to generate velocity profile of each block. Therefore, the machining time is increased when the number of G01 blocks is increased. To reduce the machining time, corner blending has been used to smooth the corner shape of adjacent blocks. Because the tool path generated by corner bending dose not reach the commanded endpoint, error of the interpolated tool path exists. The objective of this study was to present a method to determine block overlap time to limit tool path error generated by corner blending. An algorithm to calculate tool path error with respect to block overlap time was also proposed. Performance of the proposed algorithm to limit tool path error was demonstrated in this study.