Abstract:

Based on the optimum circular contour approximation method, we propose a novel estimation model for estimating the contour errors in realtime, which overcomes the shortcomings of the conventional methods for freeform curves, such as complex approximate calculation of contour error process, huge calculation, and incapability of practical application in realtime tasks. The feedback of the feed systems and the interpolation data of the CNC are read and recorded in real time to calculate the contour error vector. The double fuzzy and variable region adaptive control algorithm is applied in biaxial NC systems. Two typical contours are processed in the test machine tool and the comparative experiments show that the double fuzzy control with variable region for contouring error control based on the optimum circular contour approximation method can obtain satisfactory contour precision.

Key words: CNC;feed servo system;contour error;selfadaption