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External Representation of Product Definition Data



Bradford Smith


In December 1983 the International Organization for Standardization initiated Technical Committee 184 on Industrial Automation Systems. Subcommittee four was formed at that time to work in the area of representation and exchange of digital product data. The term Product Data denotes the totality of data elements which completely define a product for all applications over its expected life cycle. Product Data includes the geometry, topology, tolerances, relationships, attributes and features necessary to completely define a component part or an assembly of parts for the purposes of design, analysis, manufacture, test, inspection and product support. Very little if any process data is included, with the exception of aspects such as a heat treat specification. The product model is expected to be informationally complete for purposes such as generating manufacturing process instructions, directing quality control testing and performing product support functions. This paper will detail the strategy behind the development of the ISO project, will identify the various technical resources that have been brought together to develop, standardize and use product data technology, will give the status of the effort as of early 1989 and will enumerate project plans for the balance of 1989.
NIST Interagency/Internal Report (NISTIR) - 89-4166
Report Number


ISO, geometry, topology, tolerances, product data


Smith, B. (1989), External Representation of Product Definition Data, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 23, 2024)


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Created January 1, 1989, Updated November 10, 2018