Abstract: To accurately and effectively evaluate the influence of cumulative deviation in different assembly sequences on the product assembly quality, an assembly sequence deviation propagation model and a quality evaluation approach based on degree of dimensional variation are established. To acquire degree of dimensional variation, assembly-feature adjacency matrix and geometrical-feature tolerance matrix are established. According to the matrixes mentioned above, deviation propagation model with information of assembly sequence is automatically created. On the basis of the cumulative deviation calculated through deviation propagation model, the degree of dimensional variation is acquired. Following the evaluation rules, the assembly sequence can be comprehensively evaluated. The designer is able to obtain the assembly sequence with best assembly quality and improve the design tolerance of parts. Finally, a special machine for artificial gemstone is taken as an example to verify the effectiveness of the approach.

Key words: Assembly sequence, Degree of dimensional variation, Deviation propagation, Evaluation of assembly quality