Disassembly sequence plan generation using a branch-and-bound algorithm

This paper presents an approach to generate disassembly sequence plans (DSP ) automatically for product recycling and remanufacturing. An algorithm is defined first that generates a geometrically based disassembly precedence m atrix (DPM) from a CAD drawing of the product. The DPM is then used to gene rate a hierarchical disassembly tree (HDT) that represents the feasible DSP . Generation of the HDT, i. e. generation of all feasible DSP, is NP- compl ete. Thus, to keep the size of the HDT manageable, the branching and boundi ng processes are controlled using two user-defined variables. The first, w, controls the enumeration of the HDT, while the second, v, controls the bou nding procedure in the HDT along with an evaluation function. The evaluatio n function incorporates tool changes, changes in direction of movement duri ng disassembly along with individual part characteristics (e. g. high- valu ed parts, parts with hazardous content, etc.). The resulting HDT is called the reduced HDT (RHDT) since it only represents as many (near-) optimum DSP as the size of v. Experimental results demonstrate the applicability and e ffectiveness of the methodology.