Abstract:This paper introduces a method that the position of outline work parts can be discerned and defined automatically based on machine vision. On the visible operating platform, the image edge of the outline work parts placed any-angle is restarted and its characteristic is abstracted by relaxes recovers algorithm. The machining program of the work parts for numerical control machine can be produced automatically based on the edge characteristic. The simulation experiment shows that the research can satisfy the demand of NC machining without special fixture. Keywords: machine vision, edge characteristic, process path, relaxes recovers, outline work parts.