The principle and application of cutting-point virtual tool radius compensation for ellipsoidal outer contour finishing using a ball end mill

A novel cutter radius compensation method named cutting-point virtual tool radius compensation (CPVTRC) is presented in the finishing of ellipsoidal outer contour. CPVTRC, which corresponds to a virtual tool established at cutting point, is realized through parametric programming which is powerful in solving special manufacturing problems and exhibits great industrial application prospect. The parametric program for ellipsoidal outer contour finishing is given based on the algorithm of CPVTRC. The corresponding amount of the virtual tool radius per layer is calculated via the cutting-point coordinates and the elliptical outer offset curve parametric equation of the current layer. And it is inputted into corresponding registers online using programmable data input command G10L12, and then called through cutter compensation command G41/G42 before interpolation of the ellipse in the current layer. Consequently, the ellipse per layer of ellipsoid is approached via tiny line segments using CPVTRC method. The results of simulation based on VERICUT software and experiment based on a 3-axis vertical computer numerical control (CNC) machine equipped with FANUC 0i-MC exhibit that CPVTRC is highly effective and correct. Furthermore, CPVTRC can extend its application to the CNC parametric programming and machining of swept surfaces.