Optimum disassembly sequence with sequence-dependent disassembly costs

This research deals with disassembly sequencing, in particular the search for the optimum disassembly sequence. The existing exact method, which is based on mathematical programming is extended to deal with situations, in which the costs of disassembly operations are sequence-dependent. This is frequently applicable in practice, due to features such as tool exchange and reorientation/redirection. Existing methods have been compared with a new approach that is discussed and successfully tested. Iteration has been applied, as it is the appropriate tool for the elimination of cyclic quasi-solutions. It is observed that a limited amount of iterations is required for eliminating cyclic quasi-solutions. A rapid convergence can be observed. This is illustrated here with a case from the literature. The new method is suitable both in assembly, repair, and end-of-life disassembly, notably in considering selective disassembly and design for life cycle. By this, optimum disassembly sequences can quickly be obtained, because the use of integer variables is avoided here. The model can be treated as a binary linear programming problem.