Research Of Three-dimensional Assembly Process Modeling Method Based On MBD

Process plays an important role in the whole life cycle of product manufacturing. In particular, assembly process has a significant effect on product quality as the last link of production. Recently, most enterprises still adapt two-dimensional process documents and engineering drawings as on-site assembly work instruction. The traditional two-dimensional process model has good standard, however, the process information separates from three-dimensional geometric model, lacks of vivid. As the fast of product update speed and the complexity of product structure, the date redundancy and inarticulate of the traditional two-dimensional process model, become the main bottleneck of assembly accuracy and efficiency.In view of the defects of two-dimensional process model, the paper defined the process information by the MBD technology, and built three-dimensional assembly process model based on MBD. The specific research work is as follows:1) Establish three-dimensional assembly process model based on MBD. The paper established part process information model and procedure model based on MBD, through defining part PMI(product manufacturing information) and product installation information based on MBD, and combined the two models to establish three-dimensional assembly process model based on MBD.2) Establish three-dimensional assembly process model based on ontology. In view of the rich semantic relations of the three-dimensional assembly process model, the paper constructed the assembly process ontology to express three-dimensional assembly process model based on MBD, established the semantic network of assembly process and gave its structured record based on semantic through explicating the semantic relations between concepts.3) Build the platform of the three-dimensional assembly process modeling based on HOOPS. In order to realize the practical applications of the theory, the paper built the three-dimensional assembly process modeling system based on MBD, and integrated three-dimensional AO production function under the platform.The three-dimensional assembly process model will remove series of defects of data redundancy and expression unclear, improve the efficiency of assembly and ensure the assembly accuracy. The use of MBD makes the method of product definition and process data transfer produce qualitative leap, and promote the development of digital manufacturing.