ASSEMBLY DIFFERENTIATION IN CAD SYSTEMS

This work presents a data model for differentiating and sharing assembly design (AsD) information during collaborative design. Joints between parts are an important aspect of assembly models that are often ambiguous when sharing of models takes place. Although various joints may have similar geometries and topologies, their joining methods and process parameters may vary significantly. It is possible to attach notes and annotations to geometric entities within CAD environments in order to distinguish joints; however, such textual information does not readily prepare models for sharing among collaborators or downstream processes such as simulation and analysis. At present, textual information must be examined and interpreted by the human designer and cannot be interpreted or utilized by the computer; thus, making the querying of information potentially cumbersome and time consuming.This work presents an AsD ontology that explicitly represents assembly constraints, including joining constraints, and infers any remaining implicit ones. By relating concepts through ontology technology rather than just defining an arbitrary data structure, assembly and joining concepts can be captured in their entirety or extended as necessary. By using the knowledge captured by the ontology, similar-looking joints can be differentiated and the collaboration and downstream product development processes further automated, as the semantics attached to the assembly model prepares it for use within the Semantic Web