Modeling And Visualization Of Indoor And Outdoor Integrated Scene Based On Oblique Photogrammetry And BIM Technology

Smart city is upgrade of digital city.In the construction of smart city,more attention is paid to the integration and sharing of information and space,and it is particularly important to use two-dimensional or three-dimensional carriers to reflect spatial entity information in a timely and comprehensive manner.3D model is the foundation of smart city construction,and rapid and effective construction of a refined,dynamic,and integrated 3D models of cities is the critical to smart city construction.At present,most of the studies on the integrated application of 3D modeling technology have achieved the construction of outdoor models through 3D modelling technology and carried out browsing and querying functions in the visualisation platform.There are few studies on the integrated modeling of the scale reality model and the internal structure of the building,and the realization of visualization and spatial analysis on the web browser side of the B/S architecture.In this paper,oblique photogrammetry and BIM technology to carry out practical research on the establishment of refined indoor and outdoor integrated 3D scenes and model visualization,realizing the construction of indoor and outdoor hybrid models in the experimental area as well as to visualize and spatially model based on Cesium.Visualization application system for indoor and outdoor scenes were analyzed and completed.The main research contents and results of this paper are as follows:(1)Construction of an outdoor 3D real-world model based on oblique photography.On the basis of studying the basic principles and characteristics of UAV oblique photography technology and the key technology of 3D modeling of oblique photography,the design of industrial data acquisition and 3D real scene modeling is carried out,and the practical application of large scene model establishment based on Context Capture was studied,an improved modelling scheme of image control point correlation and aerial triangulation was proposed,and the 3D real scene modeling of large-scale outdoor scenes in the experimental area was completed,and the model was optimized and repaired and the accuracy was analyzed.(2)Construction of BIM-based 3D building models for urban interiors.Analyzed the key technologies of BIM technology modeling in the field of construction,understood the classification and application fields of BIM software,discussed a practical method of building indoor parametric 3D models based on BIM in the architectural design stage,and selected experiments in the large scene research area BIM indoor 3D architectural model construction is carried out in the area.(3)The indoor and outdoor integrated 3D model of the research area was constructed,and a web-based integrated visualization application system for indoor and outdoor scenes was developed.Using 3D Tiles as the integrated container of tilt and BIM heterogeneous data,based on the metadata spatial index structure expansion mechanism and visual rendering rules,and using the tile metadata nesting relationship,a hybrid model organization method that integrates tilt and BIM heterogeneous data is proposed;Using Java Script for front-end development,develop indoor and outdoor scene integration and visualization system based on Cesium open source map engine,load and visualize the formatted 3D model on the Web side;realize 3D fusion scene browsing and spatial calculation And space analysis function,so that indoor and outdoor 3D scenes are displayed in multiple detail levels,and at the same time meet the application requirements of interactive analysis and management.