Method for quickly acquiring and fusing terrain and calculating water level volume relation

Abstract

The invention provides a terrain rapid acquisition and fusion and water level volume relation calculation method, which comprises the following steps: dividing the space in a drainage basin into three categories: a flood detention space, a flood discharge space and a reservoir area, specifically adopting a relatively efficient surveying and mapping scheme, arranging image control points in combination with a slope terrain, and setting an aerial survey route of an unmanned ship in combination with a river curvature radius. Measurement sections and the like are arranged in combination with the distribution condition of a to-be-measured area of a reservoir and the river bending degree, the surveying and mapping workload is reduced while the precision is guaranteed, the topographic data acquisition time is shortened, topographic data of multiple layers are integrated by adopting a certain index, errors generated in the data processing process are reduced, and the accuracy is improved. High-precision and large-area complete topographic data are formed, and construction and management of hydraulic engineering are supported.

Description

Technical Field

[0001] The present invention belongs to the technical field of water flow evolution, and in particular relates to a method for quickly acquiring and fusing terrain and calculating the relationship between water level and volume, and specifically relates to a method for quickly acquiring and fusing terrain and calculating the relationship between water level and volume based on the differences in the characteristics of flood storage space, flood discharge space, and flood control space, combining coarse and fine density. Background Art

[0002] In the early planning, surveying and design stages of water conservancy project construction, accurate onshore and underwater terrain data are needed to design the construction plan of the water conservancy project and determine the eight major storage capacities of the designed water conservancy project, including total storage capacity, effective storage capacity, dead storage capacity and beneficial storage capacity. Among them, flood regulation storage capacity, flood interception storage capacity, flood control storage capacity and combined storage capacity play a vital role in flood regulation and prevention. The accuracy of storage capacity is one of the important factors that determine whether the flood control strategy is reliable, and it has a huge impact on the control of flood disasters in the basin and the safety of life and property of local people. In the management and operation scheduling of completed reservoirs, accurate onshore and underwater terrain data can analyze or verify the silt scouring and siltation of the reservoir, changes in storage capacity in different periods, etc., to support the long-term operation, maintenance and management of the completed reservoirs, and indirectly ensure the flood control, power generation, irrigation and other functions of the reservoir.

[0003] All of these rely on the accurate and rapid acquisition of land and underwater terrain data. The main methods at present are to use drones to survey the land terrain, use unmanned boats to measure the underwater terrain of the rivers and reservoirs in the surveyed area, and then manually splice the land and underwater terrain based on experience. In the above process, first, the land terrain data surveyed by drones is affected by factors such as vegetation obstruction, flight altitude restrictions, and steep terrain. The terrain data in some areas cannot be directly measured and need to be re-surveyed or corrected. In areas with complex terrain, manual judgment, re-survey and correction are required; second, the unmanned boat needs to completely cover the entire water surface according to the path planned by traditional methods (such as Figure 1 ), when the area to be measured is large, the workload of unmanned ships in measuring underwater terrain is large, the operation time is long, and the manpower and financial resources consumed are large. The underwater terrain conditions in different terrain areas are also different. Affected by factors such as water flow velocity, blind spots, vegetation obstruction, and shallow grounding, unmanned ships are prone to erroneous measurement data, obstructed movements, and instrument damage when encountering complex underwater terrain, which brings difficulties to the accurate acquisition of underwater terrain; thirdly, due to factors such as errors in the conversion of geographic plane coordinate systems and elevation systems and errors in the measurement process itself, there are inconsistencies, overlaps, conflicts, and missed measurements in the land terrain data obtained by drone aerial surveys and the underwater terrain data measured by unmanned ships. Some data need to be modified manually, which is greatly affected by personal experience and habits and consumes manpower.

[0004] Faced with the above difficulties, there is currently no complete and efficient method to quickly and accurately measure land and underwater terrain and integrate multi-source terrain data in areas with different terrains at a relatively low cost. Summary of the invention

[0005] To solve the above problems, the present invention proposes a method for rapid acquisition, fusion and calculation of water level and volume relationship of terrain. This method is a method for rapid acquisition, fusion and calculation of water level and volume relationship of terrain based on the coarse and fine combination of density and sparseness of the characteristics of flood storage and detention space, flood discharge space and flood control space. This method follows the idea of ​​sub-scale mapping and multi-granularity fusion, reduces the workload of land terrain measurement by unmanned aerial vehicles and underwater terrain measurement by unmanned ships, improves the measurement efficiency of terrain, and simultaneously fuses multi-source terrain data on shore and underwater to improve the accuracy of data, facilitates the calculation of flood storage capacity of flood storage and detention space (flood storage and detention areas and shoal dikes), channel storage capacity of flood discharge space (river channel), and storage capacity of flood control space (reservoir area), guarantees the construction and management of water conservancy projects, and ensures the economic benefits of the projects.

[0006] In order to realize the above technical features, the object of the present invention is achieved as follows: a method for rapid terrain acquisition, fusion and water level volume relationship calculation, comprising the following steps: Step 1: For large-scale flood storage and detention spaces, L2-1 level macroscopic rapid mapping of terrain, sky and ground integration is carried out based on satellite remote sensing, UAV and RTK; Step 2: For long-distance flood discharge spaces, L2-2 intermediate observation and mapping based on satellite remote sensing, RTK and unmanned ships is implemented; Step 3: For small-scale reservoir areas, implement L3-level microscopic fine mapping based on drones and unmanned boats; Step 4: Use data interest technology to store and retain floodwaters at the spatial level, flood discharge spatial level, and flood interception spatial level, combining coarse and fine sparse and dense levels to construct a flood control project data base and extract the water level-volume relationship of each project.

[0007] The specific calculation method in step 1 is as follows: Step 1.1, using the DEM digital elevation model in satellite remote sensing DEM data to partition and lay out image control points; Step 1.2: Conduct drone aerial survey of local areas.

[0008] The specific calculation process in step 1.1 is: Step 1.1.1: Input DEM data with a resolution of 0.5~2m, and use the slope function in the 3D Analyst toolbox in ArcGIS to calculate and output the slope of the large area of ​​flood storage space. ; Step 1.1.2, Slope The grading standards are as follows: (1); Step 1.1.3, evenly arrange 3 to 5 image control points in the area with slope grade 1; Step 1.1.4: Arrange image control points along the dividing line between slope grades one and two and between grades two and three, so that 1 to 2 image control points are arranged per square kilometer of flood storage space.

[0009] The specific calculation process in step 1.2 is: Step 1.2.1, divide the area with slope grade II and III into the test area, use the 2000 National Geodetic Coordinate System as the plane coordinate system, and use the 1956 Yellow Sea Height Datum as the elevation system; Step 1.2.2, according to the focal length of the camera lens on the drone and pixel size , and ground resolution Calculate relative flight altitude , the calculation formula is as follows: (2); Step 1.2.3, the drone flies at a relative altitude In the aerial survey of the area to be measured, the plane control network and the elevation control network are measured using network RTK. Each control point is measured twice, and the measurement results of the plane control network and the elevation control network are calculated respectively. The calculation formula is as follows: (3); (4).

[0010] Where: For the The position of each image control point in the plane control network; For the plane control network When the image control points are measured for the first time Coordinates in direction; For the plane control network When the image control point is measured for the second time Coordinates in direction; For the plane control network When the image control points are measured for the first time Coordinates in direction; For the plane control network When the image control point is measured for the second time Coordinates in direction; For the The location of each image control point in the height control network; It is the first When the image control points are measured for the first time Coordinates in direction; It is the first When the image control point is measured for the second time Coordinates in direction.

[0011] Beneficial effects of the present invention: The present invention proposes a method for rapid acquisition, fusion and water level volume relationship calculation of terrain based on the differences in the characteristics of flood storage space, flood discharge space and flood control space. The space in the basin is divided into three categories: flood storage space, flood discharge space and reservoir area. A relatively more efficient surveying and mapping scheme is adopted in a targeted manner. Image control points are arranged in combination with the slope terrain, the aerial survey route of the unmanned ship is set in combination with the curvature radius of the river, and the measurement section is arranged in combination with the distribution of the reservoir area to be measured and the degree of river curvature. While ensuring the accuracy, the surveying and mapping workload is reduced, the time for acquiring terrain data is shortened, and certain indicators are used to integrate terrain data at multiple levels, reduce the errors generated in the data processing process, and form high-precision, large-area complete terrain data to support the construction and management of water conservancy projects.

[0012] Advantage 1: This method reduces the workload of surveying and mapping. Image control points or measurement sections are arranged at different levels according to different surveying or layout rules. For example, the slope is graded in step 1, and the number and density of image control points in different areas of different slopes are different, which reduces the workload of image control point arrangement. In step 2, typical river sections are selected according to the river curvature radius, and unmanned boats perform underwater topography measurement on typical river sections, avoiding the above-mentioned Figure 1 In order to reduce the huge workload of all the measurements shown in the figure, the water area to be measured in the reservoir is divided into six categories in step 3, and different section layout rules such as the spacing of sounding lines are set according to the water surface morphology of the reservoir, which reduces the total number of measurement sections to be laid out, thereby reducing the workload of surveying and mapping.

[0013] Advantage 2: This method can obtain high-precision terrain in areas that cannot be directly measured. The terrain data initially obtained based on steps 1-3 does not include data on terrain areas that cannot be measured due to factors such as vegetation obstruction, flight altitude restrictions, and steep terrain. These areas cannot be directly measured by drones, or unmanned ships are prone to run aground. This method constructs the correlation between typical sections at each level and the terrain of the adjacent area, combines multi-source terrain data, and uses methods such as geographically weighted regression and Kriging interpolation algorithms to fit, calculate, and correct data to obtain the terrain of the area to be measured, such as the geographically weighted regression method in step 1, the use of lidar to correct errors in step 2, and the oblique photography and Kriging interpolation algorithm in step 3.

[0014] Advantage 3: This method fully considers the errors in data processing and makes multiple corrections, resulting in a small error. In step 1, after obtaining high-precision terrain data using the geographically weighted regression method, the data is fused and corrected based on the image control points combined with satellite remote sensing DEM data. In step 2, the different water levels in the river channel in different periods of flood discharge space are combined to divide it into land terrain and underwater terrain. Multi-source terrain data such as satellite remote sensing terrain data are introduced to construct a "satellite-unmanned ship measurement of river channel underwater terrain" relationship map. In step 3, the terrain data is analyzed section by section to see if it is reasonable, and the data that exceeds the error range is eliminated. At the same time, the Kriging interpolation algorithm is combined to reduce the error. In step 4, the overlap index is introduced as the basis for the fusion correction of land and underwater terrain data at all levels. The Kriging interpolation algorithm is used to correct the data when eliminating conflicting and overlapping data during the multi-source data fusion process.

[0015] Advantage 4: This method forms a method and system for mapping and integrating large-scale terrain data, forming a flood control project data base, and based on the data base, analyzes and calculates various related relationships that can indicate the flood control capacity of the basin, covering a wider range of content and considering more comprehensive factors. From the formation to the evolution of floods, large-scale construction of water conservancy projects, etc., more than just local terrain data is required. This method acquires and processes data from three aspects: flood storage space, flood discharge space, and reservoir area, covering different types of spatial types with different terrain characteristics from upstream to downstream of the basin. For example, in step 4, the terrain data of the three levels are integrated to obtain a multi-level data set and complete terrain data in the basin. It can be calculated at different levels or in the entire basin to obtain the water level volume relationship at each scale, which is used to evaluate the flood control capacity of the basin. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 This is the moving path of the unmanned ship using the traditional method.

[0018] Figure 2 It is the overall flow chart of the present invention.

[0019] Figure 3 It is a process flow chart of a specific embodiment of the present invention.

[0020] Figure 4 Slope division of flood storage space and layout of image control points (local area).

[0021] Figure 5 DEM elevation map of flood storage space (local area).

[0022] Figure 6 Schematic diagram of flood discharge space measurement section (partial river section).

[0023] Figure 7 DEM elevation map of flood space (partial river section).

[0024] Figure 8 Topographic map of the reservoir area.

[0025] Fig. 9 Water level and volume change curve of Shilong Reservoir in Jingshan City and surrounding areas. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, some aspects of the present invention are further described in detail below in conjunction with the accompanying drawings and specific implementations. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention.

[0027] Embodiment 1: A method for quickly acquiring and fusing terrain and calculating the relationship between water level and volume, comprising the following steps: Step 1: For large-scale flood storage and detention spaces, L2-1 level macroscopic rapid mapping of terrain, sky and ground integration is carried out based on satellite remote sensing, UAV and RTK; Step 1.1, using the DEM digital elevation model in satellite remote sensing DEM data to partition and lay out image control points; Step 1.1.1: Input DEM data with a resolution of 0.5~2m, and use the slope function in the 3D Analyst toolbox in ArcGIS to calculate and output the slope of the large area of ​​flood storage space. ; Step 1.1.2, Slope The grading standards are as follows: (1); Step 1.1.3, evenly arrange 3 to 5 image control points in the area with slope grade 1; Step 1.1.4: Arrange image control points along the dividing line between slope grades one and two and between grades two and three, so that 1 to 2 image control points are arranged per square kilometer of flood storage space.

[0028] Step 1.2: Conduct drone aerial survey of local areas.

[0029] Step 1.2.1, divide the area with slope grade II and III into the test area, use the 2000 National Geodetic Coordinate System as the plane coordinate system, and use the 1956 Yellow Sea Height Datum as the elevation system; Step 1.2.2, according to the focal length of the camera lens on the drone and pixel size , and ground resolution Calculate relative flight altitude , the calculation formula is as follows: (2); Step 1.2.3, the drone flies at a relative altitude In the aerial survey of the area to be measured, the plane control network and the elevation control network are measured using network RTK. Each control point is measured twice, and the measurement results of the plane control network and the elevation control network are calculated respectively. The calculation formula is as follows: (3); (4).

[0030] Where: For the The position of each image control point in the plane control network; For the plane control network When the image control points are measured for the first time Coordinates in direction; For the plane control network When the image control point is measured for the second time Coordinates in direction; For the plane control network When the image control points are measured for the first time Coordinates in direction; For the plane control network When the image control point is measured for the second time Coordinates in direction; For the The location of each image control point in the height control network; It is the first When the image control points are measured for the first time Coordinates in direction; It is the first When the image control point is measured for the second time Coordinates in direction.

[0031] Step 2: For long-distance flood discharge spaces, L2-2 intermediate observation and mapping based on satellite remote sensing, RTK and unmanned ships is implemented; Step 3: For small-scale reservoir areas, implement L3-level microscopic fine mapping based on drones and unmanned boats; Step 4: Use data interest technology to store and retain floodwaters at the spatial level, flood discharge spatial level, and flood interception spatial level, combining coarse and fine sparse and dense levels to construct a flood control project data base and extract the water level-volume relationship of each project.

[0032] Embodiment 2: The present embodiment provides a method for quickly acquiring and fusing terrain and calculating the relationship between water level and volume based on the differences in characteristics of flood storage space, flood discharge space, and flood control space, comprising the following steps: Step 1: For large areas of flood storage space, implement L2-1 level macro rapid mapping of terrain, sky and ground based on satellite remote sensing, UAV and RTK.

[0033] Taking the Shilong Reservoir and surrounding areas in Jingshan City in 2024 as an example, for the flood storage space contained therein, high-resolution terrain data is input, the slope is divided using ArcGIS, and image control points are arranged. The schematic diagram of local terrain slope division and image control point arrangement is shown in the figure. Figure 4 After calculating the plane control network and elevation control network, the satellite remote sensing DEM data is corrected and integrated to obtain the topographic data of the flood storage space. Figure 5 shown.

[0034] Step 2: For long-distance flood discharge spaces, implement L2-2-level observation and mapping of the sky, earth and water based on satellite remote sensing, RTK and unmanned ships.

[0035] Taking the Shilong Reservoir and surrounding areas of Jingshan City in 2024 as an example, for the flood discharge space contained therein, the river dry season is selected for drone aerial survey, and coordinate transformation and error correction are performed to obtain land terrain data; the water system is generated from the terrain data, and the threshold coefficient of this embodiment is Take 0.6, calculate the river curvature radius and set the measurement section. The schematic diagram of the measurement section of the river section in the flood discharge space is as follows: Figure 6 After fitting the cross-section data, the land terrain data and underwater terrain data are integrated to obtain the topographic map of the river section in the flood discharge space as shown in the figure. Figure 7 .

[0036] Step 3: For small-scale reservoir areas, implement air-water integrated L3-level micro-scale detailed mapping based on drones and unmanned boats.

[0037] Taking the Shilong Reservoir and surrounding areas of Jingshan City in 2024 as an example, the horizontal control network and elevation control network of the reservoir area included therein are calculated as shown in Table 1 and Table 2, and the topographic map of the area is finally obtained as shown in Figure 8 .

[0038] Table 1 Comparison of the results of the second measurement of the plane control network (partial points)

[0039] Table 2 Comparison of geodetic heights measured twice by the elevation control network (partial points)

[0040] Step 4, according to the idea of ​​"scaled construction and multi-granularity integration", use data interest technology to divide the flood storage space (flood storage area and beach embankment) level, flood discharge space (river channel) level, and flood control space (reservoir) level, and combine coarse and fine sparse and dense to build a "valuable" flood control project data base, and extract the water level and volume relationship of each project. The terrain data obtained in steps 1 to 3 are integrated using AcrGIS to construct a flood control project data base, with a calculation interval of 0.01m, a check flood level of 69.99m, the lowest underwater point elevation of 45.2m, and a volume calculation range of 45.2m~69.99m. The For loop iterator is used to calculate multiple times to obtain the water level and volume change curve as shown below Fig. 9 .

Claims

1. A method for rapid terrain acquisition, fusion and water level volume relationship calculation, characterized in that: The following steps are involved: Step 1: For large-scale flood storage and detention spaces, L2-1 level macroscopic rapid mapping of terrain, sky and ground integration is carried out based on satellite remote sensing, UAV and RTK; Step 2: For long-distance flood discharge spaces, L2-2 intermediate observation and mapping based on satellite remote sensing, RTK and unmanned ships is implemented; Step 3: For small-scale reservoir areas, implement L3-level microscopic fine mapping based on drones and unmanned boats; Step 4: Use data interest technology to store and retain floodwaters at the spatial level, flood discharge spatial level, and flood interception spatial level, combining coarse and fine sparse and dense levels to construct a flood control project data base and extract the water level-volume relationship of each project.

2. According to claim 1, a method for rapid terrain acquisition, fusion and water level volume relationship calculation is characterized in that: The specific calculation method in step 1 is as follows: Step 1.1, using the DEM digital elevation model in satellite remote sensing DEM data to partition and lay out image control points; Step 1.2: Conduct drone aerial survey of local areas.

3. According to claim 1, a method for rapid terrain acquisition, fusion and water level volume relationship calculation is characterized in that: The specific calculation process in step 1.1 is: Step 1.1.1: Input DEM data with a resolution of 0.5~2m, and use the slope function in the 3D Analyst toolbox in ArcGIS to calculate and output the slope of the large area of ​​flood storage space. ; Step 1.1.2, Slope The grading standards are as follows: （1）； Step 1.1.3, evenly arrange 3 to 5 image control points in the area with slope grade 1; Step 1.1.4: Arrange image control points along the dividing line between slope grades one and two and between grades two and three, so that 1 to 2 image control points are arranged per square kilometer of flood storage space.

4. According to claim 1, a method for rapid terrain acquisition, fusion and water level volume relationship calculation is characterized in that: The specific calculation process in step 1.2 is: Step 1.2.1, divide the area with slope grade II and III into the test area, use the 2000 National Geodetic Coordinate System as the plane coordinate system, and use the 1956 Yellow Sea Height Datum as the elevation system; Step 1.2.2, according to the focal length of the camera lens on the drone and pixel size , and ground resolution Calculate relative flight altitude , the calculation formula is as follows: （2）； Step 1.2.3, the drone flies at a relative altitude In the aerial survey of the area to be measured, the plane control network and the elevation control network are measured using network RTK. Each control point is measured twice, and the measurement results of the plane control network and the elevation control network are calculated respectively. The calculation formula is as follows: （3）； （4）； Where: For the The position of each image control point in the plane control network; For the plane control network When the image control points are measured for the first time Coordinates in direction; For the plane control network When the image control point is measured for the second time Coordinates in direction; For the plane control network When the image control points are measured for the first time Coordinates in direction; For the plane control network When the image control point is measured for the second time Coordinates in direction; For the The location of each image control point in the height control network; It is the first When the image control points are measured for the first time Coordinates in direction; It is the first When the image control point is measured for the second time Coordinates in direction.

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