Research On Refined 3D Modeling And Smart Park Application Based On UAV Oblique Images

The Oblique Photogrammetry technology of UAV?Unmanned Aerial Vehicle?is to use a set of image data with a certain degree of overlap to quickly build a real scene 3D model with clear texture,which has been widely used in mapping,smart city construction and other fields.Consumer UAV equipped with single-lens aerial photography,represented by DJI_Phantom series,are favored by many practitioners for their flexible operation and high cost performance.However,there are still many problems in the construction of 3D model based on UAV Oblique Photogrammetry.For example,the influence of different camera angle on the data acquisition and 3D model construction is often ignored when the single-lens aerial camera is used to obtain image data.The 3D model at the shelter of ground objects cannot be expressed and the texture of the region of interest is fuzzy and not clear.At present,most of the real scene 3D models are mainly used for browsing and display,and the 3D models and vector data cannot be well managed in GIS which carried out space query and analysis and other operations.This paper starts with the research on the acquisition of oblique image data.First,it studies the influence of the aerial camera angle on the acquisition of oblique image data and the construction of the 3D model of the real scene.Then,it uses the air-ground integration technology to realize the refined construction of the 3D model of the real scene at the point cloud level and the model level.Finally,based on the SuperMap 3D visualization platform,a smart park application visualization system was established to realize the application of the real scene refined 3D model in the smart park.The main work of this paper includes:?1?Construction of mathematical model of aerial camera angle.From the perspective of resolution,the maximum and minimum resolution and ratio relationship of single image were firstly analyzed,and the continuous angle was separated to determine the further research angle.Then the ratio relation between horizontal resolution and vertical resolution of strabismus is studied to determine the aerial camera angle.At last,the camera DJIFC6310 carried by the DJI_Phantom₄Pro UAV was taken as the main research object,and the angle of the aerial camera was set as 33°,45°,50°,53° and 60° respectively for experiments,to verify the correctness of the mathematical model of the aerial camera angle.?2?Using air-ground integration technology to integrate modeling.Aiming at the problems such as drawing at the shelter of the eaves and fuzzy texture of the model details,a refined 3D model was established using air-ground integration technology on the basis of the optimal angle of the aerial camera;and according to the specific requirements of fusion modeling for image data acquisition,the fusion modeling was realized from point cloud level and model level,and the applicable scope of the two methods were summarized and analyzed.This paper analyzes the specific requirements of fusion modeling for image data acquisition,and realizes fusion modeling from point cloud level and model level,and summarizes and analyzes the applicable scope of the two methods.With the help of manual repair technology,the holes in the traditional method and fusion modeling process are repaired to establish a refined 3D model.Point cloud level fusion modeling is a unified processing of near-earth image data and aerial image data,generating dense point cloud data and texture mapping to build a 3D model;Fusion modeling at the model level is to build a 3D model based on a unified reference coordinate system,by which the image data obtained by the two methods are respectively aerial triangulation.?3?The samrt park application visualization system was designed and implemented.The refined 3D model can accurately describe the location and form of spatial entities,and provide powerful technical means for urban planning,design approval,completion acceptance,etc.,which is of great significance for the construction of smart parks.First,format conversion and configuration file generation of 3D model data are carried out in SuperMap iDesktop software to establish 2D vector surface data set required for dynamic monomer.Then,SuperMap iServer 10i software was used to publish the 3D model service,which provided the foundation for the development of 3D data service system.Finally,the API interface provided by SuperMap iClient3D for WebGL was used to design and develop the samrt park application visualization system,realizing the functions of flood analysis,visual analysis,individual information query and simple spatial calculation,and providing new ideas for the application of real scene 3D model.