Product information exchange using open assembly model: Issues related to representation of geometry information

The objective of this paper is to discuss the main issues for product information exchange through the Open Assembly Model (OAM). The OAM model provides a base level product model that is open, simple, generic, expandable, independent of any vendor software and product development process, and capable of engineering context that is shared throughout the product lifecycle. Two of the main issues in the OAM model are the representation of geometric information of the artifacts (and assembly features) and maintenance of the consistency of the product information among relevant classes based on geometry information. This paper considers the geometry information at three levels: 1) basic geometric information of artifact with position and orientation information, 2) assembly features and their interrelations, and 3) detailed geometric information of all features in the artifact. In addition to geometric information, other relations/associations between the classes in the Unified Modeling Language (UML) based OAM model are maintained by constraints written in Object Constraint Language (OCL). This information structure in the UML and OCL is then mapped into the Extensible Markup Language (XML) for easy information exchange. XML is commonly used and supported by many softwares. Therefore, integration of XML with UML will provide an excellent tool for internet based collaboration.