Research on mixed design modeling method for virtual assembly

DUAN Xiao-kun1， WU Bo1， ZHAO Xiu-lin2
（1. School of Mechanical Science and Technology， Huazhong University of Science and Technology， Wuhan 430074， China；
2. CSR Qingdao Sifang Locomotive and Rolling Stock Co.， Ltd.， Qingdao 266111， China）

Abstract： Aiming that the existing virtual assembly modeling methods can't provide complete information model for the assembly sequence planning，the advantages and disadvantages of the bottom-up and the top-down assembly modeling applied to the virtual assembly were analyzed. According to the requirements of assembly sequence planning，a mixed design method for product assembly modeling was put forward，which combined with the advantages of the two design methods. To make the assembly model contains the product structure of hierarchical relationship information，top-down modeling method was used in the overall design. In the process of detail design，the bottom up modeling method was used to make the assembly model contain the constraint relation of parts. Through the modeling application examples，the feasibility of the mixed design method in virtual assembly and the model information can be extracted have been proved. The results indicate that the model obtained by the mixed design method satisfies the requirements of the virtual assembly，provides the complete model information for the virtual assembly sequence planning.
Key words： virtual assembly technology； assembly modeling； bottom-up； top-down；mixed design