Research On Disassembly Sequence For Bogie Conceptual Design

Because of modern complex product systems, such as high speed train, aircraft, ship, etc, have complicated internal relations among subsystems, components and parts, the early phase of the product development process, such as conceptual design, is vital to following designing segments, thereby previous research on conceptual model feasibility become especially important. However, the current research of disassemblability analysis are almost on detailed design but not conceptual design, as a consequence this study highlights the need to research on complex product’s conceptual model, particularly on bogie from high speed train. A new disassembly sequence planning method is introduced by integrating undirected graph("undigraph" for short), hierarchy graph and engineering semantics disassembly precedence. Rational disassembly sequence is finally obtained through the weight combining analysis method based on "sequence synthesis" method and Saaty’s weight analysis theory, which enabling sequence optimal selection. A corresponding software system named ADST(Automated Disassembly Sequence Tool) within CATIA has been developed and apply it on bogie of high speed train,ensuring the theory proposed giving full support to the disassemblability analysis in conceptual design of complex product system. The main contents are as following:(1)"Undi-hierarchy graph" model is derived from function modularization feature and hierarchy feature from product structure tree and geometric CAD conceptual model in top-down design; and a new disassembly sequence planning method-UE method is designed based on both graph model and engineering semantic disassembly precedence, and this UE method is applied on bogie conceptual model successfully.(2) A weight combining analysis method is generated for optimal selecting disassembly sequence, which calculates weight vectors for index-"disassembly distance","tool changes","direction changes" and "feasible directions", the method is according to the "sequence synthesis " method and Saaty’s weight analysis theory, and is applied on disassembly sequence.(3) Based on CATIA CAA,for secondary development, to build ADST, practice it on bogie conceptual model and prove the theory proposed is applicable to disassemblability analysis of complex product conceptual design.