Feature-oriented change propagation impact assessment for complex mechanical 3D CAD assembly model based on complex network

3D CAD assembly model is appropriately changed to meet diverse functions and performance requirements of the product, which will cause a series of change propagations within the 3D assembly model. To predict and assess in advance the scope of change propagation impact for 3D assembly model reuse, an approach for feature-oriented change propagation impact assessment for complex mechanical 3D CAD assembly based on a complex network is proposed. The feature and part relation network for describing 3D CAD parts and assembly models are constructed respectively from the feature granularity and part granularity perspectives. Through analysing the mapping relationship among features, part and assemblies, the feature assembly relation network for the 3D CAD assembly model is constructed. The complex network centrality and entropy are employed to evaluate the importance of assembly topological structure of assembled parts, for assessing change propagation impact in the 3D assembly model at the part level. Subsequently, the feature change propagation impact on the 3D assembly model is comprehensively evaluated considering the feature change propagation path, feature change propagation index and feature change propagation evolution law at the feature level. The 3D CAD assembly model of the worm gear reducer is taken as an example, and the feasibility and effectiveness of the proposed approach are verified. .It is helpful for feature change scheme optimisation and control of change propagation in 3D CAD assembly model.