Tying together design, process planning and machining with STEP-NC technology

While simulation has been successful in tying design and process planning into an iterative loop, machining has traditionally been a downstream terminus of the manufacturing cycle. Simulation of machining has proven difficult due to the highly dynamic and nonlinear nature of the material removal process. Consequently, actual machining must be performed to determine the suitability of designs and process plans. The nature of the programming interface to machine tools has been an obstacle to information flow in both directions. Toward the machine tool, useful design and process information is reduced to primitive tool path motion statements. From the machine tool, no automatic data paths exist, so machinists must translate results into recommendations for design or process changes manually. The advent of STEP (ISO 10303) data for numerical control, or STEP-NC, promises to rectify these problems by providing full product and process data to the machine tool controller at run time and an automatic path back to these upstream activities using technologies such as XML. This paper describes STEP-NC and early experiences that show how these benefits can be achieved.