Abstract: A novel method is proposed to calculate the minimum distance from tool to free-form surface, to solve tool interference problem in 5-axis NC sculptured surface machining. Projecting points on surface to axis of cutter, calculating the minimum distance from axis of cutter to surface, the amount of interference can be determined directly; a corrective method for interference cutter-location is proposed. The problem of global interference is solved successfully, and the method has high efficiency and precision.

Key words: 5-axis NC machining, Cutter location correction, Global interference, Minimum distance