We are always committed to the development, application service and industrialization of high-precision
3D laser series products, and provide users with multi industry and full scene solutions.
Application Of HiScan Shipborne 3D Laser Mobile Measurement System In River And Reservoir Survey
In recent years, with the development of LiDAR, 3D laser scanners and mobile measurement systems have also been tried to be applied to river surveying. It can scan objects in 3D, so as to quickly obtain high-density 3D coordinates of the target. It is also a data acquisition means of real-time, initiative, non-contact, surface measurement.
Ⅰ. Project Overview
The survey area is located in a city in the central and western China, mainly in canyon and mountain terrain. The continuous peak on both sides are about 700-800 meters above the river, and the narrowest part of the river is more than 100 meters wide. According to the requirements of the project content, considering the topographic characteristics of the canyon waterway, and the convenient conditions of vegetation, resident, traffic, control, water level station and water level variation of the river section on both banks, the river section between G13 and G14 is selected for the project ( as shown in Figure 1 ).
Fig 1 Diagram of survey area
Ⅱ. Project requirements and difficulties
1. Achievement requirements: Obtain the large-scale topographic map of the survey area, generate the digital elevation model (DEM), and generate panoramic registration data.
2. Difficulties of the project: The river is wide and turbulent, terrain of the canyon changes greatly, and vegetation on both sides of the river is lush.
1. Field data acquisition
HiScan shipborne 3D laser mobile measurement system is used in this project, which can quickly obtain orientation, 3D point cloud and panoramic image data in the process of carrier movement. The field data acquisition process of waterway survey mainly includes base station set up, IMU alignment, laser point cloud and panoramic photo collection, etc.
2. Internal data processing
In the internal data processing, the Inertial Explorer solution software is used for post-processing to calculate the position and orientation information of the IMU trace, and then the data fusion software developed by Hi-Cloud is used for laser data fusion to generate point cloud files. After a series of pre-processing processes such as point cloud denoising filtering, point cloud classification, image and point cloud registration, and data format conversion, the image and point cloud are registered. Finally, with the help of the point cloud processing software HD_3LS_SCENE and HD PtVector of Hi-Cloud, digital mapping can be performed on the basis of laser point clouds and panoramic images, in order to realize the collection of 2D polylines, 3D polylines and 3D points, which is convenient for the production of river topographic maps.
Fig 2 HiScan shipborne 3D Laser Mobile Measurement System
Ⅳ. The result display
1. Large scale topographical map
Through the internal mapping software of the shipborne 3D laser mobile measurement system, the massive point cloud and panoramic data can be loaded and displayed, topographic elements can be collected based on point cloud and panoramic processing, and the data achievement of topographic map can be produced. Figure 3 shows the mapping result.
Fig 3 topographical map
2. DEM generation
After thinning, denoising and filtering of the laser point cloud in the survey area, the accurate DEM on both sides of the river can be generated by setting the DEM grid size of 2m*2m. At the same time, contour lines and DEM rendering maps can be superimposed and displayed, as shown in Figure 4 and Figure 5.
Fig 4 DEM
Fig 5 3D model of both sides of the survey area
3. Panorama registration data
Both laser point cloud and panoramic image data can be obtained at the same time by the shipborne 3D laser mobile measurement system . Using the engineering data after panoramic registration, the ground feature measurement can be performed based on the panoramic image, and it is also convenient and direct to interpret ground feature elements and identify the ground features category attributes (as shown in Figure 6).
Fig 6 Panoramic image and laser point cloud registration
Ⅴ. Project summary
In view of the low efficiency of using traditional surveying and mapping methods, the slow updating cycle of mapping, the inability to reflect the changes of topography on both sides of the waterway in time, and the insufficient response ability to rapid surveying and mapping in the survey of river and reservoir areas, this paper collects data in the survey by applying the shipborne 3D laser mobile measurement system, and the point cloud obtained is regular and the element information on both sides of the river is clear and complete, which can fully meet the requirement of the DLG, DEM processing and various terrain analysis. And the point cloud and image data can also be used for modeling and simulation analysis, which fully shows that the Hi-Cloud HiScan shipborne 3D laser mobile measurement system has the characteristics of high precision, high efficiency and rich achievements, and can be well extended to the survey application of rivers, reservoir areas and other water areas.
Ⅵ. Product recommendation
HiScan shipborne 3D Laser Mobile Measurement System