Planning of products assembly and disassembly

Previous research in assembly process planning focused on the generation and evaluation of all possible assembly plans for the product under consideration. While this approach ensures completeness, it is inefficient, time consuming and costly. This paper presents the results of our research which aims at improving the efficiency of the assembly planning process and producing optimal assembly and disassembly plans. Geometric feasibility and accessibility constraints are introduced to reduce the size of the directed assembly graph to be searched. Four criteria have been introduced and formalized to optimize the resulting assembly plans. These are stability, number of reorientations, concurrency of operations, and grouping of similar operations. Graph search methods which guarantee optimality of plans are briefly described. Examples of real products are used to illustrate the generation of: assembly plans, disassembly plans for repair and maintenance, and plans to recover from assembly execution errors.