Notice of RetractionUnderstanding the STEP-NC data model for computer numerical control

STandard for the Exchange of Product data-compliant Numerical Control (STEP-NC) is a new model of data transfer between CAD/CAM systems and CNC machines. It remedies the shortcomings of ISO 6983 by specifying machining processes rather than machine tool motion, using the object-oriented concept of Workingsteps. STEP-NC is being developed concurrently under two different subcommittees of ISO Technical Committee 184, Industrial automation systems and integration so that two different standards, ISO 14649 Data model for computerized numerical controllers and ISO 10303-238 Application interpreted model for computer numeric controllers are generated, both of which can be represented in 10303-21. In this paper, ISO 14649 NC program in Part 21 relative to Example 1 in the ISO 14649-11 is explained in detail so that people can easily understand the object-oriented data model and the advantages of ISO 14649 from the actual example other than abstract and unintelligible theory. Probably, more beginners can get some revelation so that STEP or STEP-NC can get more attention and their development will be faster.