Abstract: Influence factors of geometric feasible assembly sequence in actual application are studied. Based on the requirements of practical process rules and the integrity of index system, concrete calculation method and quantitative formulas of evaluation index system are proposed. According to the parallelism of actual assembly sequence, a unified algorithm—“optimal order reference set” of assembly performance membership degree calculation for assembly unit is put forwarded. Concrete application steps are verified through an example. Analysis of the example shows that the proposed method satisfies the requirements of practical process rules and the integrity of index system. The optimal selection of geometric feasible assembly sequence is realized. The new method has realistic significance to automatic assemble application.

Key words: Assembly sequence, Evaluation indexes, Fuzzy evaluation, Sequence optimum