In order to accelerate the promotion of the integration of real estate housing land, collective construction land and other rural real estate right registration work. In 2016, Yuncheng Yanhu District completed the cadastral survey of the right to use homestead and collective construction land, laying a solid foundation for the registration of real estate. Now we have officially and comprehensively launched the Property Confirmation and Registration of Rural Real Estate in Yanhu District and the 3D Real Estate Modeling and Procure Project. The work contents include the rural real estate ownership survey, 1:500 scale topographic map project mapping, oblique photogrammetry, 3D modeling, and software development of the real estate registration and certification system.
Star Space (tianjin) Technology Development Co., LTD., is a geographic information industry service provider integrating 3D data acquisition and 3D geographic information platform research and development.
The main business of the company is airborne lidar aerial survey, vehicular mobile laser scanning survey, ground laser scanning survey, unmanned aerial vehicle digital aerial survey, 4D product production and database construction, 3D digital city construction, 3D digital solution and 3D animation production, GIS software development, etc. Its services cover basic surveying and mapping, urban planning, land management, smart city construction, urban emergency response, mobile supervision, as well as survey and mapping of highway, oil pipeline and water conservancy industries.
Yuncheng Salt Lake District is located in the southwest of Shanxi Province, located at the junction of Qin, Jin and Yu provinces in the middle reaches of the Yellow River, connecting Xia County in the east, Yongji and Linyi in the west, Zhongtiao Mountain and Pinglu and Ruicheng in the south, and Jiwang Mountain and Wanrong, Jishan and Wenxi in the north. The area is 41 kilometers wide from east to west, 62 kilometers long from north to south, with a total area of 1237 square kilometers.
The project involves a total of 19 towns, 287 administrative villages, about 130,000 plots of land, measuring an area of 100 square meters. During the project, in strict accordance with the requirements of relevant documents and standards, the project carried out comprehensive rural real estate ownership survey, 1:500 scale topographic map project mapping, oblique photogrammetry, three-dimensional modeling, and software development of real estate registration and certification system. The contract amount of the project was more than 40 million yuan.
Two sets of field aviation equipment are used in this project. The DJI M300 UAV is equipped with Chengdu Rainpoo D2 PSDK camera, and the M600 is equipped with DG3 PROS camera. Internal processing using 30 computer cluster processing, computer equipped with 2080TI or 3080 graphics card, 96G memory, three AT(aerotriangulation) servers with 10T solid-state hard disk, node machine 256 solid-state hard disk.Rainpoo is a professional drone mapping camera manufacturer,and Rainpoo oblique camera is widely used in the aerial surveying project.The high-grade quality images collected with the camera is the effect guarantee of the 3d modeling.
Overview of Aviation and Flight
In this project, the design altitude was 83 m, the ground resolution (GSD) was 1.3cm, and the operation was carried out according to the heading/side overlap of 80/70% of the conventional cadastral measurements. The route was laid in the north-south direction as far as possible, and more than 4 million original photos were obtained. The spacing of the GCP is about 150 meters, and the periphery and corner of the measurement area increased quantity properly.
The area of the villages in the survey area is basically about 0.3 square kilometers, some of which reach more than 1 square meters, and the number of photos is about 20,000. There are few technical difficulties in the processing of oblique model, which is basically a pipeline operation. Cadastral mapping and model modification are mainly the tactics of human sea . Functions such as model monomers, data storage, information display and other functions are handled by the software independently developed by our company.
Due to the large number of photos, M3D AT(Aerial Triangulation) was used for data processing. All the projects have the same origin and the same block size, so that the block code of the results of each project is unique, which is convenient for model storage and search. The block combination table is shown below:
At present, this project has not been completely completed, and only a simple check and statistics are made on the intermediate results of the model. Most of the problems can be dealt with by re-empting the interior industry and drawing the picture again, while a few need to fly again.
In general, the accuracy of the model is good, and the pass rate is higher than 95%. In terms of model, DG3 model is a little better than D2 model under the same conditions. Problems of models mainly include the following points: terrain relief caused by overlapping degree or resolution does not meet the requirements, rainy weather or fog caused by insufficient illumination or visibility.
Screenshot of The Model
Before flight, RTK equipment is used to measure the precise coordinates of ground feature points (such as zebra crossings, marking lines, L-type targets and other significant feature points) in the measurement area as checkpoints to check the model accuracy in the later stage. The CS2000 coordinate system is used for the checkpoint and the fitting parameter height is used for the elevation. The following is the situation of our measurement of feature points. Due to the limited space, we only choose a few of them to show.