建筑物BIM与实景三维模型融合方法研究

Building information model (BIM) and reality 3D model are two kinds of building models in civil engineering and geographic information fields, respectively. The merged model may not only be used to present the detailed information of inner building, but also to analyze the interaction between building and the around environment, which can provide good support to the application in different fields of the smart city. The difficulties of the fusion are building geometric information fusion, semantic integration of sub-components of building and spatial position registration. For this, the framework of fusion was described in which the IFC model was selected as the source model and 3DTitles model as the target model. The workflow and method of the fusion were discussed, including reconstruction of BIM model according to building components, geometric information transformation of the model using interchange format obj and glTF, spatial position registration according to the tie-points and SVD algorithm, and semantic mapping of building components regrading to the format of the reality 3D model. Finally, experiment on buildings of a company is engaged to verify the proposed fusion method and display the fusion results. Overall, the method discussed in the paper is able to realize the fusion of BIM model and the corresponding reality 3D model in perspective of semantics, geometry, and location. Meantime, the method can automatically realize the fusion steps except select registration tie-points, so as to quickly build an integrated indoor and outdoor building model.