Subassembly identification method based on CAD data

Abstract

Seen the significant number of parts constituting a mechanism, assembly or disassembly sequence planning became a very hard problem. The subassembly identification concept can constitutes the most original way to solve this problem particularly for complex product. This concept aims to break down the multipart assembly product into particular number of subassemblies, and each subassembly is constituted by a small number of parts. Consequently the generation of assembly or disassembly sequence planning between parts can be determined relatively easily because it becomes between the subassemblies constituting the product. Then, each subassembly is assembled or disassembled using the same approach. In literature subassemblies identification approach from CAD model is not very developed and still a relevant research subject to be improved. In this paper, a novel subassemblies identification approach is presented. This proposed approach starts with the exploration of the CAD assembly data to get an adjacency matrix. Then, the extracted matrix is enriched by adding the contact in all directions in order to determine and to classify the base parts initiator of each subassembly. The next step is to identify subassemblies using a new matrix called sum matrix obtained from contact all direction matrix and fit matrix. For better discussing and explaining the stages of the proposed approach an example of CAD assembly product is presented in all sections of this paper.