The choice of the sequence in which parts or subass em blies are put together in the mechanical assembly of a product can drastical ly affect the efficiency of the assembly process. Unlike metal cutting operation s where computer aided system have been available for some 15 to 25 years to hel p manufacturing engineers in generating cutting sequences and NC programs, the m ajority of assembly planning tasks in automobile body design is still manually p erformed by assembly designers according to their past experiences. This has prolonged the production lead time and time to market. This paper describes a p rocedure to automatically derive all the feasible assembly sequences for automob ile body assembly. The procedure is based on a mathematical model of the automob ile body, obtained through the definitions of the connection matrix and contract ed matrix. These two matrices represent the precedence constraint knowledge amon g components and subassemblies. The possible subassemblies are automatically det ected by satisfying some mathematical conditions applicable to these matrices. F or each subassembly and the whole product, all the possible assembly sequences a re generated by rearranging the initial connection sub-matrix and the contracte d matrix. The procedure is applicable to compliant component assemblies, suc h asthe automobile body assembly, aircraft frame assembly, and can solve the "combinatorial explosion" problem efficiently.
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