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Data Exchange of Parametric CAD Models Using ISO 10303-108



Junhwan Kim, Mike Pratt, Raj G. Iyer, Ram D. Sriram


Modern CAD systems generate feature-based product shape models with parameterization and constraints. Until recently, standards for CAD data exchange among different CAD systems were restricted to the exchange of pure shape information. These standards ignored the parameters, constraints, features, and other elements of ?design intent? present in the model to be transferred. This paper suggests an implementational foundation for CAD data exchange with parametric information for the preservation of design intent, based on the use of newly published parts of the International Standard ISO 10303, which is informally known as STEP ? STandard for Exchange of Product model data. A case study is presented, which employs a hypothetical STEP application protocol (AP) using Parts 55, 108 and 111 of ISO 10303. A prototype translator based on this AP has been implemented and tested. The paper reports on the experience gained in parametric data exchange.
NIST Interagency/Internal Report (NISTIR) - 7433
Report Number


constraints, Data exchange, design intent, parameterization, parametric CAD models, STEP


Kim, J. , Pratt, M. , Iyer, R. and Sriram, R. (2007), Data Exchange of Parametric CAD Models Using ISO 10303-108, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed June 13, 2024)


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Created June 30, 2007, Updated October 12, 2021