A GREEN DECISION SUPPORT SYSTEM FOR INTEGRATED ASSEMBLY AND DISASSEMBLY SEQUENCE PLANNING USING A PSO APPROACH

摘要

A green decision support system is presented to integrate assembly and disassembly sequence planning and to evaluate the two costs in one integrated model. In a green product life cycle, it is important to determine how a product can be disassembled before the product is planned to be assembled. For an assembled product, an assembly sequence planning model is required for assembling the product at the start, whereas a disassembly sequence planning model is needed for disassembling the product at the end. In typical assembly and disassembly sequence planning approaches, the two sequences and costs are independently planned and evaluated. In this research, a new integrated model is presented to concurrently generate and evaluate the assembly and disassembly sequences. First, graph-based models are presented for representing feasible assembly sequences and disassembly sequences. Next, a particle swarm optimization (PSO) method with a new encoding scheme is developed. In the new PSO encoding scheme, a particle is represented by a position matrix defining an assembly sequence and a disassembly sequence. The assembly and disassembly sequences can be simultaneously planned with an objective of minimizing the total of assembly costs and disassembly costs. The test results show that the presented method is feasible and efficient for solving the integrated assembly and disassembly sequence planning problem. An example product is implemented and illustrated in this paper.