Similarity comparison of mechanical parts to reuse existing designs

In actual practice, many new mechanical parts are designed by modifying existing ones. In this way, time and effort can be saved by not having to design parts from scratch. Design time would be further reduced if there were an efficient way to search for existing similar designs. Furthermore, a new part design can be very efficiently generated by modifying the dimensions on the features of the existing part if a part with a similar feature set and the corresponding modeling history can be easily searched from the existing part library.In this paper, a two-step similarity comparison method for B-rep files is proposed. Overall appearances are compared first, and then detailed features are compared. In this way, existing parts with similar feature set in addition to similar overall shape can be identified from the part library. Once the similar part is identified, its modeling history can also be used for parametric modeling if the existing part was designed by a feature-based modeler.