Exchange of Parametric CAD ModelsJIANG Hua1,PRATT J Michael2,SRIRAM D Ram2 (1.School of Power and Mechanical Engineering,Wuhan University,Wuhan 430072,China; 2.Design and Process Group,National Institute of Standards and Technology,Gaithersburg,MD 20899-0001,USA)A method to exchange digital CAD model construction history data using ISO10303 is presented. The primary intention of this research is to demonstrate the utility of ISO10303-108 in achieving parametric CAD model exchange between commercial CAD systems. ISO10303-108,still under development,has been used to represent geometric and dimensional constraints on the sketch profile. Schemas from Parts 42,50 of ISO 10303 are also used. ISO10303-42 is adopted to represent geometric and topological information and ISO10303-50 is used to represent the mathematical expression.CAD model exchange; construction history; parameters; constraints