Applying the topological relationships of form features to retrieve part files from a CAD system

The efficient retrieval of stored CAD files is an area that has received si gnificant attention in recent years. Several Product Data Management produc ts have been developed, most of which are based on the use of coding concep ts to retrieve designs. However, the limited number of codes that can be us ed limits the flexibility of part shape representation and also versatility in retrieving existing drawings. In this paper, an integrated approach usi ng topological relationships among form features as the search indices is p roposed. The use of a feature adjacency graph and also a feature topologica l relation graph that acts as the interface enables this approach to transl ate the feature-based B-Rep model of a part that is stored in the CAD syste m into topological relationships that are stored in a relational database. In addition, five types of queries based on topological relationships are u sed to aid the retrieval of designs. The proposed technique for design retr ieval is more convenient than traditional coding based methods.