Research On Space Ground Data Acquisition And Fusion Processing Method Of Water Conservancy Project BIM

With the continuous breakthrough of big data,cloud computing and Internet of things technology,BIM Technology ushered in a great development era.BIM Technology focuses on the information carrier function of digital model,which can integrate data information of all stages of the whole life cycle of the project,dynamically display the changes of properties and economic value on the project time axis.The essence of BIM Technology is the dynamic correlation system of integration of engineering digital graphics and relevant information,and the relevant information will be updated with the change of graphics structure.The theory of digital graphics media makes "digital graphics" a five-dimensional information carrier which sets geometric features and topological attributes dynamically over time.The data of engineering planning,design,construction,operation and maintenance can be directly obtained and feedback from the graphics.The key of digital graphics media theory is the collection of digital graphics information,which includes forward modeling and reverse modeling.Oblique photogrammetry is a common technique in reverse modeling in engineering field.It breaks the pose limitation that traditional photogrammetry can only obtain terrain information from vertical perspective.Based on two-dimensional image information,3D model reconstruction is realized according to a series of algorithm rules.However,there are some limitations in 3D modeling,which can not fully express the detailed features of object surface.Focusing on the technical problems of 3D real scene modeling of water conservancy project tilt image,this paper focuses on the key technologies and optimization strategies of data acquisition and processing from the perspective of air ground collaboration.Aiming at the characteristics of tall structure,irregular shape and complex texture information of water conservancy project,the corresponding 3D reconstruction method of air ground data fusion is proposed,Integrating multiple data sources can effectively solve various problems of 3D model reconstruction;Based on the actual water conservancy project,the fusion modeling experiment of tilt image and near ground image is carried out.The main research work of this paper includes the following aspects:1.Based on the actual engineering form and surrounding environment,the research on image data acquisition method is carried out,and the aerial photography parameters,layout mode of control points,image information acquisition system and other influencing factors are comprehensively analyzed.A multi-mode inclined image acquisition scheme for water conservancy engineering is proposed,which integrates the whole route method,local superposition method and fixed-point surround method,and its key steps are optimized;This paper selects a prefabricated three camera array mobile acquisition system to obtain high-definition near ground images of structural engineering,summarizes the specific implementation process of near ground image acquisition,and expands the channels and methods of image information acquisition.2.The key technologies of the Fusion Modeling of the air to ground image are studied by combining the low altitude tilt image and the ground close range image.The technologies such as the joint adjustment of the Air-to-Ground image and the dense matching of the Air-to-Ground images are studied in depth.The integration of the data from the spatial level,the point cloud level and the information level is realized,and the cluster model based on parallel computing can realize the fast fusion modeling,The feasibility of fusion is proved from the theoretical level.3.Based on the key technologies of the air to ground data fusion modeling,the total technology scheme of the data acquisition and processing of the open space obtained is applied to a water conservancy project in Shaanxi Province.The multi-source and massive image data with time series are calculated and analyzed according to a single high-density image as the storage unit,The results show that the three-dimensional model reconstruction method of the air to ground fusion improves the geometric structure precision of the model significantly,and the overall precision can reach cm level,and the texture quality of the local structure is optimized,which has important engineering practical value,and the feasibility of fusion is verified in practice.