Abstract: A novel method for assembly sequences planning is proposed based on the theory of directional connection graph. By introducing the directional graph into represent the mating conditions of parts in a product, a new model of product representation, directional assembly connection graph (DACG), is constructed. Then the properties of DACG are given. The directional cut set analysis based on DACG is brought forward to generate assembly sequences. Compared with cut set analysis, the new method generates less invalid sequences, and has less computational complexity. In order to reduce the invalid sequences further, the directional cut set analysis of monotone and linear assembly is studied. The approach to add constrains on the assembly sequences generation algorithm is discussed also. Analytical and experimental results are presented to demonstrate the effectiveness of the approach.

Key words: Assembly sequences generation, Cut set analysis, Directional assembly connection graph, Directional graph