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A Planning Model for Unifying Information Modeling Languages for Product Data Specification (PDES)



Joan Tyler


A voluntary group called the IGES/PDES Organization is leading the Product Data Exchange specification (PDES) project. The goal is to create a specification focused on exchanging product models with sufficient information content as to be interpretable directly by advanced computer aided design and computer aided manufacturing (CAD/CAM) ampliation programs. There are many technical issues that must be resolved if PDES is to become a standards. This paper describes a mechanism for resolving issues surrounding the use of multiple information modeling paradigms. Several diverse modeling languages have been used to define and formalize the information needed to fully represent the multiple disciplines needed for a complete product model. This prompted committee of the IGES/PDES Organization to undertake a research project to unify these divergent paradigms. Some intermediate results of this project are discussed including the Planning Model, which is intended to serve as a baseline for future development of a neutral repository for storing semantics. This document describes a plan to construct a prototype STEP-based manufacturing cell to demonstrate how parts are produced in a STEP environment. The manufacturing cell is an integral part of an overall project to establish the National PDES Testbed at the National Institute of Standards and Technology (NIST). The Testbed was initiated in 1988 under the sponsorship of the U.S. Department of Defense Computer-aided Logistic Support (CALS) program. A major goal of the Testbed is to provide technical leadership in a national effort to implement a complete and useful specification for the exchange of product data. This specification must be designed to meet the needs of American industry and the CALS program.
NIST Interagency/Internal Report (NISTIR) - 4234
Report Number


IGES, PDES, information content, modeling languages, product data


Tyler, J. (1990), A Planning Model for Unifying Information Modeling Languages for Product Data Specification (PDES), NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD (Accessed February 27, 2024)
Created December 31, 1989, Updated October 12, 2021