Three-dimensional coal mine area earth volume calculation method and device based on unmanned aerial vehicle inclination data

Abstract

The invention provides a three-dimensional coal mine area earthwork volume calculation method and device based on unmanned aerial vehicle inclination data. The three-dimensional coal mine area earthwork volume calculation method comprises the steps that an early-stage three-dimensional model, corresponding early-stage DOM data, a later-stage three-dimensional model and corresponding later-stage DOM data of the early-stage three-dimensional model before and after filling and excavation of a target mine area are obtained based on the unmanned aerial vehicle inclination data; based on the earlier-stage DOM data and the later-stage DOM data, extracting a target area vector and an interpolation area vector corresponding to the target mining area; based on the target area vector and the interpolation area vector, performing earth volume differential block calculation by combining the early-stage three-dimensional model and the later-stage three-dimensional model to obtain an earth excavation volume set and an earth filling volume set corresponding to the target mining area; and rendering and drawing according to the excavation volume set and the fill volume set to obtain an excavation and fill volume rendering result corresponding to the target mining area. According to the invention, three-dimensional coal mine area earth volume calculation can be efficiently and accurately realized.

Description

Technical Field

[0001] The present invention relates to the technical field of earthwork volume calculation, and particularly to a three-dimensional coal mine area earthwork volume calculation method and device based on drone tilt data. Background Art

[0002] During the process of coal mine exploitation operations, the accurate calculation of excavation and filling earthwork volume is of crucial significance for various aspects such as the planning of the mining area, resource utilization, cost control, and environmental protection.

[0003] Traditional earthwork volume calculation methods such as the grid method and the contour method mainly rely on field measurements. By laying out grids of a certain size in some areas of the fieldwork site, surveyors need to set up a large number of survey control points in the mining area and use instruments such as level gauges and total stations to measure the elevation and planar position of each point one by one. This method not only consumes a large amount of human, material, and time costs, but also faces many difficulties in the complex coal mine area environment. For example, when there are steep mine pit slopes, large areas of accumulations, and frequently changing mining areas, it is difficult to effectively guarantee the accuracy and integrity of the measurement data. There are also some studies on calculating excavation and filling earthwork volume based on DEM or three-dimensional models. However, it is generally difficult to control the time phase, resolution, and accuracy of DEM, and it relies on commercial software. At the same time, it cannot well display the distribution effect of the excavation and filling areas; while those based on three-dimensional models often calculate with a single period and a fixed elevation benchmark, and at the same time do not consider the influence of ground interference objects such as trees and bulldozed objects, resulting in a relatively large randomness of errors and can only be used as a reference quantity. These methods are difficult to meet the requirements of rapid coal mine exploitation operations and accurate and intuitive calculation results, and also bring technical difficulties to subsequent auditing work.

[0004] With the rapid development of drone technology, the drone oblique photogrammetry technology has emerged and gradually been widely used in the surveying and mapping field. This technology can quickly obtain large-area high-resolution image data and construct a three-dimensional model with rich texture information and high precision by carrying multiple sensors on the drone and shooting ground targets from different angles; however, there are still deficiencies in the current application research on the calculation of excavation and filling earthwork volume in coal mine areas based on the data format of drone oblique three-dimensional models. Existing data processing processes and algorithms often cannot efficiently and accurately extract the key information for earthwork volume calculation and efficiently and intuitively display the excavation and filling results when dealing with three-dimensional model data in special topographies and complex operating environments such as coal mine areas. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a three-dimensional coal mine area earthwork volume calculation method and device based on drone tilt data, which can efficiently and accurately calculate the earthwork volume of a three-dimensional coal mine area.

[0006] In a first aspect, an embodiment of the present invention provides a three-dimensional coal mine area earthwork calculation method based on UAV tilt data, including: Based on the UAV tilt data, obtain the pre-construction three-dimensional model of the target mining area before earth filling and excavation, its corresponding pre-construction DOM data, the post-construction three-dimensional model, and its corresponding post-construction DOM data; Based on the pre-construction DOM data and the post-construction DOM data, extract the target area vector and the interpolation area vector corresponding to the target mining area. The target area vector is the area where the earth filling and excavation volume needs to be calculated, and the interpolation area vector is the sub-area with ground interference objects within the area where the earth filling and excavation volume needs to be calculated; Based on the target area vector and the interpolation area vector, combined with the pre-construction three-dimensional model and the post-construction three-dimensional model, perform differentiable block calculation of the earthwork volume to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area; According to the excavation earthwork volume set and the filling earthwork volume set, perform rendering to obtain the rendering result of the excavation and filling earthwork volume corresponding to the target mining area.

[0007] In an implementation manner, based on the target area vector and the interpolation area vector, combined with the pre-construction three-dimensional model and the post-construction three-dimensional model, perform differentiable block calculation of the earthwork volume to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area, including: Determine the virtual camera pose according to the target area vector, and control the virtual camera to adjust its pose according to the virtual camera pose so that the front of the virtual camera faces the pre-construction three-dimensional model and the post-construction three-dimensional model; Divide the target area vector into multiple first differentiable rectangular blocks; Perform elevation differentiable interpolation on the interpolation area vector to generate an interpolation triangular mesh corresponding to the interpolation area vector; Based on the first differentiable rectangular blocks and the interpolation triangular mesh corresponding to the interpolation area vector, combined with the pre-construction three-dimensional model and the post-construction three-dimensional model within the field of view of the virtual camera, determine the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area.

[0008] In an implementation manner, the virtual camera pose includes the camera position coordinates and the camera rotation angle; determining the virtual camera pose according to the target area vector includes: Determine the minimum circumscribed rectangle corresponding to the target area vector; Take the center coordinates of the minimum circumscribed rectangle as the plane coordinates of the virtual camera; and, based on the intersection point of the perpendicular line passing through the center coordinates and the pre-construction three-dimensional model or the post-construction three-dimensional model, obtain the height coordinates of the virtual camera; the plane coordinates and the height coordinates form the camera position coordinates corresponding to the virtual camera; Based on the included angle of the long side vector of the minimum circumscribed rectangle in the Cartesian coordinate system, determine the camera rotation angle corresponding to the virtual camera.

[0009] In one embodiment, the interpolation region vector carries a label for characterizing whether the interpolation region vector belongs to before or after earthwork filling and excavation. Performing elevation differentiable interpolation on the interpolation region vector to generate an interpolation triangular mesh corresponding to the interpolation region vector includes: For each boundary point in the boundary point set corresponding to the interpolation region vector, based on the label carried by the interpolation region vector, obtain the intersection point between the vertical line passing through the boundary point and the pre - period three - dimensional model or the post - period three - dimensional model, so as to generate an interpolation point set, where the elevation value of the intersection point in the interpolation point set is the same as the elevation value of its corresponding boundary point; Divide the interpolation region vector into multiple second - differentiable rectangular sub - blocks. When the vertices of the second - differentiable rectangular sub - blocks fall within the interpolation region vector, add the vertices of the second - differentiable rectangular sub - blocks to the interpolation point set, and the elevation value of the vertices in the interpolation point set is 0; Use the elevation values of the intersection points in the interpolation point set to interpolate the elevation values of the vertices in the interpolation point set to obtain a target interpolation point set; Generate an interpolation triangular mesh corresponding to the interpolation region vector based on the target interpolation point set.

[0010] In one embodiment, based on the first - differentiable rectangular sub - blocks and the interpolation triangular mesh corresponding to the interpolation region vector, combining the pre - period three - dimensional model and the post - period three - dimensional model within the virtual camera's field of view, determining the earth - excavation volume set and earth - filling volume set corresponding to the target mining area includes: Perform the following operations on any first - differentiable rectangular sub - block: When the central coordinate of the first - differentiable rectangular sub - block intersects with the interpolation region vector, based on the label carried by the interpolation region vector, use the interpolation triangular mesh corresponding to the intersecting interpolation region vector to update the pre - period three - dimensional model or the post - period three - dimensional model within the virtual camera's field of view; Determine the intersection points between the vertical line passing through the central coordinate of the first - differentiable rectangular sub - block and the updated pre - period three - dimensional model and the updated post - period three - dimensional model respectively, so as to determine the volume difference corresponding to the first - differentiable rectangular sub - block; Based on the positivity or negativity of the volume difference, save the volume difference to the earth - excavation volume set or the earth - filling volume set.

[0011] In one embodiment, based on the label carried by the interpolation region vector, using the interpolation triangular mesh corresponding to the intersecting interpolation region vector to update the pre - period three - dimensional model or the post - period three - dimensional model within the virtual camera's field of view includes: If the label indicates that the interpolation region vector belongs to before earthwork filling and excavation, use the interpolation triangular mesh corresponding to the intersecting interpolation region vector to replace the part corresponding to the interpolation region vector in the pre - period three - dimensional model within the virtual camera's field of view; If the label indicates that the interpolation region vector belongs to the cut-and-fill area, the interpolation triangular mesh corresponding to the intersecting interpolation region vector is used to replace the part corresponding to the interpolation region vector in the later three-dimensional model within the virtual camera's field of view.

[0012] In one implementation, rendering is performed according to the set of excavation volumes and the set of filling volumes to obtain the rendering result of the cut-and-fill volumes corresponding to the target mining area, including: Determine the maximum excavation volume value and the minimum excavation volume value in the set of excavation volumes, and determine the maximum filling volume value and the minimum filling volume value in the set of filling volumes; Divide the specified color band into a first sub-color band and a second sub-color band; Determine the rendering step length for excavation according to the maximum excavation volume value and the minimum excavation volume value, and based on the rendering step length for excavation, determine the mapping relationship between the excavation volume values in the set of excavation volumes and the color band indices in the first sub-color band; and, determine the rendering step length for filling according to the maximum filling volume value and the minimum filling volume value, and based on the rendering step length for filling, determine the mapping relationship between the filling volume values in the set of filling volumes and the color band indices in the second sub-color band; Perform rendering based on the mapping relationship to obtain the rendering result of the cut-and-fill volumes corresponding to the target mining area.

[0013] In one implementation, after obtaining the pre-construction three-dimensional model of the target mining area and its corresponding pre-construction DOM data, and the post-construction three-dimensional model and its corresponding post-construction DOM data based on the UAV oblique data, the method further includes: Determine the same reference ground feature point and its corresponding pre-construction elevation value and post-construction elevation value from the pre-construction three-dimensional model and the post-construction three-dimensional model; Determine the offset matrix based on the pre-construction elevation value and the post-construction elevation value corresponding to the reference ground feature point; Use the offset matrix to fine-tune the pre-construction three-dimensional model and the post-construction three-dimensional model so that the pre-construction elevation value corresponding to the same reference ground feature point coincides with the post-construction elevation value.

[0014] In a second aspect, the present invention further provides a three-dimensional coal mining area earthwork calculation device based on UAV oblique data, including: A data acquisition module for obtaining the pre-construction three-dimensional model of the target mining area and its corresponding pre-construction DOM data, and the post-construction three-dimensional model and its corresponding post-construction DOM data based on the UAV oblique data; A vector extraction module for extracting the target area vector and the interpolation area vector corresponding to the target mining area based on the pre-construction DOM data and the post-construction DOM data, where the target area vector is the area for which the cut-and-fill earthwork is to be calculated, and the interpolation area vector is the sub-area within the area for which the cut-and-fill earthwork is to be calculated and where there are ground interference objects; An earthwork volume calculation module, which is used to perform differentiable block calculation of earthwork volume based on the target area vector and the interpolation area vector, in combination with the pre - period 3D model and the post - period 3D model, to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area; An earthwork volume rendering module, which is used to perform rendering drawing according to the excavation earthwork volume set and the filling earthwork volume set, to obtain the rendering result of the excavation and filling earthwork volume corresponding to the target mining area.

[0015] In a third aspect, the present invention also provides an electronic device, including a processor and a memory. The memory stores computer - executable instructions that can be executed by the processor, and the processor executes the computer - executable instructions to implement the method according to any one of the first aspect.

[0016] A three - dimensional coal mine area earthwork volume calculation method and device based on UAV tilt data provided by the present invention. First, based on the UAV tilt data, the pre - period 3D model of the target mining area before and after excavation and filling, its corresponding pre - period DOM data, the post - period 3D model, and its corresponding post - period DOM data are obtained; then, based on the pre - period DOM data and the post - period DOM data, the target area vector and the interpolation area vector corresponding to the target mining area are extracted. The target area vector is the area where the excavation and filling earthwork volume is to be calculated, and the interpolation area vector is the sub - area with ground interference objects in the area where the excavation and filling earthwork volume is to be calculated; then, based on the target area vector and the interpolation area vector, in combination with the pre - period 3D model and the post - period 3D model, differentiable block calculation of earthwork volume is performed to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area; finally, rendering drawing is performed according to the excavation earthwork volume set and the filling earthwork volume set to obtain the rendering result of the excavation and filling earthwork volume corresponding to the target mining area. The above - mentioned method can quickly and efficiently obtain and process data based on the UAV - based oblique modeling scheme. Compared with the traditional on - site measurement scheme and other calculation methods, the two - dimensional result display is transferred to a 3D model. The present invention improves the controllability of the calculation scale based on the pre - and post - period 3D models. The interpolation area vector solves the problem of the influence of interference objects, realizes the visual rendering of the calculation result of the excavation and filling earthwork volume, more efficiently and intuitively reflects the calculation scale, process, and final result, ultimately effectively improving the planning and management level of the coal mine area, enhancing cost control and economic benefit evaluation, providing strong support for the audit work of mining areas, etc., and promoting the innovative application of UAV mapping technology in the coal industry.

[0017] Other features and advantages of the present invention will be described in the subsequent specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention are achieved and obtained by the structures specifically pointed out in the specification, the claims, and the drawings.

[0018] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following specifically provides preferred embodiments in conjunction with the accompanying drawings and describes them in detail as follows. Description of the Drawings

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 Flow diagram of a three-dimensional coal mine area earthwork volume calculation method based on UAV tilt data provided by an embodiment of the present invention; Figure 2 Flow diagram of the production of three-dimensional data in the mining area before and after provided by an embodiment of the present invention; Figure 3 Flow diagram of a method for determining a mask vector region provided by an embodiment of the present invention; Figure 4 Flow diagram of a differentiable method for calculating earthwork volume of excavation and filling provided by an embodiment of the present invention; Figure 5 Flow diagram of three-dimensional rendering and display provided by an embodiment of the present invention; Figure 6 Structural diagram of a three-dimensional coal mine area earthwork volume calculation device based on UAV tilt data provided by an embodiment of the present invention; Figure 7 Structural diagram of an electronic device provided by an embodiment of the present invention. Detailed Embodiments

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0022] At present, when the existing data processing processes and algorithms process the 3D model data in the special terrain and complex working environment of coal mine mining areas, they often cannot efficiently and accurately extract the key information for earthwork calculation and display the excavation and filling results efficiently and intuitively; there is a lack of a unified, efficient and accurate method system for calculating the earthwork volume of coal mine mining areas based on the data format of UAV oblique 3D models, making it difficult to give full play to the potential advantages of UAV oblique photogrammetry technology in the earthwork volume calculation of coal mine mining areas, thus restricting the improvement of the scientific and refined management level of coal mine mining operations. Based on this, the embodiments of the present invention provide a method and device for calculating the 3D earthwork volume of a coal mine area based on UAV oblique data, which can efficiently and accurately calculate the 3D earthwork volume of a coal mine area.

[0023] To facilitate the understanding of this embodiment, first, a method for calculating the 3D earthwork volume of a coal mine area based on UAV oblique data disclosed in the embodiments of the present invention will be introduced in detail. Refer to Figure 1 The flowchart of a method for calculating the 3D earthwork volume of a coal mine area based on UAV oblique data shown in the figure. This method mainly includes the following steps S102 to S108: Step S102, based on the UAV oblique data, obtain the pre-construction 3D model of the target mining area before excavation and filling, its corresponding pre-construction DOM data, the post-construction 3D model, and its corresponding post-construction DOM data.

[0024] In one example, the UAV can be controlled to collect oblique data of the target mining area before and after excavation and filling respectively, and then reconstructed based on the oblique data before and after excavation and filling to obtain the pre-construction 3D model, its corresponding pre-construction DOM (Digital Orthophoto Map) data, the post-construction 3D model, and its corresponding post-construction DOM data. Preferably, the same reference ground feature point can also be determined in the pre-construction 3D model and the post-construction 3D model, and the pre-construction 3D model and the post-construction 3D model can be fine-tuned using this reference ground feature point to eliminate the elevation error between the pre-construction 3D model and the post-construction 3D model.

[0025] Step S104, based on the pre-construction DOM data and the post-construction DOM data, extract the target area vector and the interpolation area vector corresponding to the target mining area.

[0026] Among them, the target area vector is the area for which the earthwork volume of excavation and filling is to be calculated, the interpolation area vector is the sub-area within the area for which the earthwork volume of excavation and filling is to be calculated and where there are ground interferences, the number of interpolation area vectors is at least one, the ground interferences can be trees, accumulations, etc., and the interpolation area vector carries a label, which is used to characterize whether the interpolation area vector belongs to before or after the excavation and filling. In one example, in relevant engineering software, based on the early DOM data and the late DOM data, combined with Map World (Tian Di Tu, a public service platform for geographic information) or other data sources, the target area vector corresponding to the target mining area and multiple interpolation area vectors can be extracted.

[0027] Step S106, based on the target area vector and the interpolation area vector, combined with the early 3D model and the late 3D model, perform differentiable block calculation of the earthwork volume to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area.

[0028] Among them, the excavation earthwork volume set includes the excavation earthwork volume values corresponding to some differentiable rectangular blocks within the target area vector, and the filling earthwork volume set includes the filling earthwork volume values corresponding to some differentiable rectangular blocks within the target area vector. In one example, based on the target area vector, combined with the early 3D model and the late 3D model, the differentiable rectangular blocks contained within the target area vector (denoted as the first differentiable rectangular blocks) are determined; at the same time, based on the interpolation area vector, combined with the early 3D model and the late 3D model, elevation differentiable interpolation is performed to determine the interpolation triangular network corresponding to the interpolation area vector; integrating the first differentiable rectangular blocks, the interpolation triangular network, the early 3D model and the late 3D model, the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area are determined.

[0029] Step S108, perform rendering based on the excavation earthwork volume set and the filling earthwork volume set to obtain the rendering result of the excavation and filling earthwork volume corresponding to the target mining area.

[0030] Among them, the rendering result of the excavation and filling earthwork volume is used to describe the situation of the excavation and filling earthwork volume within the target mining area in different colors. In one example, a specified color band can be divided into a first sub-color band and a second sub-color band. Based on the maximum excavation earthwork volume value and the minimum excavation earthwork volume value in the excavation earthwork volume set, the mapping relationship between the excavation earthwork volume values in the excavation earthwork volume set and the color band indexes in the first sub-color band is determined, and based on the maximum filling earthwork volume value and the minimum filling earthwork volume value in the filling earthwork volume set, the mapping relationship between the filling earthwork volume values in the filling earthwork volume set and the color band indexes in the second sub-color band is determined. Then, based on the mapping relationship, rendering is performed to obtain the corresponding rendering result of the excavation and filling earthwork volume.

[0031] The 3D coal mine area earthwork calculation method based on UAV tilt data provided by the embodiments of the present invention can quickly and efficiently acquire and process data based on the UAV tilt modeling solution. Compared with the traditional on-site measurement solution and other calculation methods, the 2D result display is transferred to a 3D model. The present invention improves the controllability of the calculation scale based on the two-phase 3D models, and the interpolation area vector solves the problem of the influence of interference objects, realizing the visual rendering of the calculation results of the excavation and filling earthwork volume, more efficiently and intuitively reflecting the calculation scale, process and final result, ultimately effectively improving the planning and management level of the coal mine area, enhancing cost control and economic benefit evaluation, providing strong support for the audit work of the mining area, etc., and promoting the innovative application of UAV mapping technology in the coal industry.

[0032] For ease of understanding, the embodiments of the present invention provide a specific implementation manner of a 3D coal mine area earthwork calculation method based on UAV tilt data.

[0033] (1) Production of 3D data of the mining area in the previous and later periods, see Figure 2 The schematic flow diagram of the production of 3D data of the mining area in the previous and later periods shown, including: collecting the tilt data of the mining area in the early stage, and obtaining the early 3D model and the early DOM data after 3D reconstruction; collecting the tilt data of the mining area in the later stage, and obtaining the later 3D model and the later DOM data after 3D reconstruction; fine-tuning the early 3D model and the later 3D model. In specific implementation, it includes the following (1.1) to (1.2): (1.1) Based on the UAV tilt data, obtain the early 3D model of the target mining area before and after excavation and filling, and its corresponding early DOM data, later 3D model and its corresponding later DOM data.

[0034] Use the UAV to collect tilt data of the target mining area before excavation and filling, and then use professional 3D reconstruction software for reconstruction to produce the early 3D model Data_pre in the early osgb (Open Scene Graph Binary) format and the corresponding early DOM data Dom_pre; after excavation and filling, collect tilt data and perform 3D reconstruction on the target mining area in the same range again to produce the later 3D model Data_last in the later osgb format and the corresponding later DOM data Dom_last.

[0035] (1.2) From the early 3D model and the later 3D model, determine the same reference ground feature point and its corresponding early elevation value and later elevation value; determine the offset matrix based on the early elevation value and the later elevation value corresponding to the reference ground feature point; use the offset matrix to fine-tune the early 3D model and the later 3D model so that the early elevation value corresponding to the same reference ground feature point coincides with the later elevation value.

[0036] Since it is an uncontrolled three-dimensional reconstruction, there may be a certain elevation error between the early three-dimensional model Data_pre and the later three-dimensional model Data_last. Therefore, it is necessary to fine-tune the three-dimensional model. Find a reference ground feature point on the three-dimensional model, such as an artificial ground feature point P1, preferably at the position of a road or the corner of a house. Use the elevation point P1 of the early three-dimensional model Data_pre as the elevation reference point. By setting the offset matrix of the later three-dimensional model Data_last, the corresponding point P1 in the early DOM data Dom_pre is made to coincide with the corresponding point P1 in the later DOM data Dom_last.

[0037] (2) Determine the mask vector region. Refer to Figure 3 the schematic flow chart of a method for determining the mask vector region as shown, including: performing vector collection by combining the early or later DOM data, Map World, and other data sources to obtain the target region vector and the interpolation region vector. Among them, the target region vector and the interpolation region vector are the mask vector regions.

[0038] This step is mainly used to output the target region vector V1 and the interpolation region vector V2 for calculating the earthwork volume of excavation and filling. The target region vector V1 is the region where the earthwork volume of excavation and filling needs to be calculated, and the interpolation region vector V2 is the region with trees, accumulations, or other ground interferences. In the embodiment of the present invention, the target region vector V1 and the interpolation region vector V2 can be outlined in the GIS software using the early DOM data Dom_pre and the later DOM data Dom_last. Among them, the interpolation region vector V2 needs to add an integer field phase value (i.e., label) to identify whether the vector region belongs to the early or later stage, where the value 1 represents the early stage, 2 represents the later stage, and 3 represents both the early and later stages; at the same time, the interpolation region vector V2 needs to ensure that the boundary points fall on the ground rather than on the interferences. At the same time, if the time difference is not very large, the target region vector V1 and the interpolation region vector V2 can also be collected through Map World or the existing target vector region results can be used; but it is necessary to ensure that the target region vector V1 and the interpolation region vector V2 are consistent with the coordinates of the early three-dimensional model Data_pre and the later DOM data Data_last.

[0039] (3) Differentiably calculate the earthwork volume of excavation and filling. Refer to Figure 4 the schematic flow chart of a method for differentiably calculating the earthwork volume of excavation and filling as shown, including: calculating the virtual camera pose according to the target region vector and the early and later three-dimensional models, and calculating the differentiable rectangular blocks; performing differentiable interpolation according to the interpolation region vector and the early and later three-dimensional models to obtain the interpolation triangular mesh; performing differentiable block calculation according to the differentiable rectangular blocks and the interpolation triangular mesh to obtain the earthwork volume of excavation and filling, including the earthwork volume set of excavation and the earthwork volume set of filling. In specific implementation, it includes the following (3.1) to (3.4): (3.1) Determine the virtual camera pose based on the target area vector, and control the virtual camera to adjust its pose according to the virtual camera pose, so that the front of the virtual camera faces the pre - three - dimensional model and the post - three - dimensional model. In one implementation, calculate a camera position coordinate Camera_P and a camera rotation angle Rotate_angle for looking down on the three - dimensional model area based on the target area vector V1, and dynamically translate and rotate the virtual camera to face the three - dimensional model directly according to the camera position coordinate Camera_P and the camera rotation angle Rotate_angle. Specifically: (3.11) Determine the minimum bounding rectangle corresponding to the target area vector.

[0040] In specific implementation, use the Rotating Calipers algorithm to calculate the minimum bounding rectangle rect of the target area vector V1. The length of the minimum bounding rectangle rect is W and the width is H.

[0041] (3.12) Take the center coordinates of the minimum bounding rectangle as the plane coordinates of the virtual camera; and, obtain the height coordinate of the virtual camera based on the intersection point of the perpendicular line passing through the center coordinates and the pre - three - dimensional model or the post - three - dimensional model; the plane coordinates and the height coordinates form the camera position coordinates corresponding to the virtual camera.

[0042] In specific implementation, take the center coordinates coor[x,y] of the minimum bounding rectangle rect as the plane coordinates of the virtual camera; set the default field - of - view angle fovy of the virtual camera, and take the long side W of the minimum bounding rectangle rect as the long side of the virtual camera's perspective transformation. According to trigonometric functions, tan(fovy / 2)=W / 2 / re_height, so the height re_height of the virtual camera relative to the surface of the three - dimensional model at this time is re_height = W / (2*tan(fovy / 2)); draw a vertical line segment L1 through the plane coordinates of the center coordinates coor[x,y]. The starting point of the vertical line segment L1 is L1_P1[coor[x],coor[y],re_height + 10000], and the end point is L1_P2[coor[x],coor[y],re_height - 10000]; perform a spatial intersection calculation between the vertical line segment L1 and the post - three - dimensional model Data_last (or the pre - three - dimensional model Data_pre). Since the three - dimensional model is triangular mesh surface data, there must be an intersection point Intersect_P[x,y,z]. Finally, obtain the three - dimensional space coordinates of the virtual camera (i.e., the camera position coordinates): Camera_P[x,y,z] = [coor[x],coor[y],re_height+Intersect_P[z]].

[0043] (3.13) Determine the camera rotation angle corresponding to the virtual camera based on the angle of the long side vector of the minimum bounding rectangle in the Cartesian coordinate system. In specific implementation, when calculating the camera rotation angle Rotate_angle of the virtual camera, it is to calculate the angle α of the vector of the long side W of the minimum bounding rectangle rect in the first quadrant or the angle β in the second quadrant of the Cartesian coordinate system. Then Rotate_angle = α or Rotate_angle = 90 - β.

[0044] Finally, determine the virtual camera pose based on the camera position coordinate Camera_P and the camera rotation angle Rotate_angle.

[0045] (3.2) Vectorially divide the target area into multiple first differentiable rectangular blocks. In specific implementation, divide the target vector area V1 into multiple first differentiable rectangular blocks. Under a sufficient number of small first differentiable rectangular blocks, the plane area of the target vector area V1 can be approximately fitted. Assume that the differential along the long side direction of the minimum bounding matrix rect is M rectangles, and this value can be dynamically adjusted according to the current area. The smaller the M value, the faster the calculation and the greater the actual error may be. On the contrary, the larger the M value, the slower the calculation and the smaller the actual error. Then the side length of each small rectangle width = W / M. So there are N = int(H / width)+1 in the wide side direction of the minimum bounding matrix rect. The total number of first differentiable rectangular blocks in the entire minimum bounding matrix rect is M * N. In actual production, the size of the first differentiable rectangular blocks is dynamically set according to the target area to control the accuracy and efficiency. The larger the M value, the higher the accuracy and the lower the calculation efficiency. On the contrary, the lower the accuracy and the higher the efficiency.

[0046] (3.3) Perform elevation differentiable interpolation on the interpolation area vector to generate an interpolation triangular network corresponding to the interpolation area vector. Specifically: (3.31) For each boundary point in the boundary point set corresponding to the interpolation area vector, based on the label carried by the interpolation area vector, obtain the intersection point between the vertical line drawn through the boundary point and the pre - period 3D model or the post - period 3D model to generate an interpolation point set. The elevation value of the intersection point in the interpolation point set is the same as the elevation value of its corresponding boundary point.

[0047] In specific implementation, according to the attribute phase value (i.e., the label) of the Feature object of the interpolation region vector V2, the corresponding three-dimensional data Data for interpolation is determined, and the set of boundary points Interpolation_P_Vec2 of the Feature object is read; perpendicular line segments are constructed to calculate the three-dimensional intersections of Interpolation_P_Vec2 and Data, generating the set of interpolation points Interpolation_P_Vec3. Exemplarily, if the attribute phase value (i.e., the label) indicates that the interpolation region vector V2 belongs to the early stage of excavation and filling, the set of boundary points Interpolation_P_Vec2 is intersected with the three-dimensional model Data_pre in the early stage, and the intersections are added to the set of interpolation points Interpolation_P_Vec3; if the attribute phase value (i.e., the label) indicates that the interpolation region vector V2 belongs to the later stage of excavation and filling, the set of boundary points Interpolation_P_Vec2 is intersected with the three-dimensional model Data_last in the later stage, and the intersections are added to the set of interpolation points Interpolation_P_Vec3.

[0048] (3.32) The interpolation region vector is divided into multiple second differentiable rectangular blocks. When the vertices of the second differentiable rectangular blocks fall within the interpolation region vector, the vertices of the second differentiable rectangular blocks are added to the set of interpolation points, and the elevation values of the vertices in the set of interpolation points are 0.

[0049] In specific implementation, based on the same minimum bounding rectangle differentiation principle as above, the Feature object is divided to obtain second differentiable rectangular blocks. If the vertices of the second differentiable rectangular blocks fall inside the Feature object, then the planar coordinates of this point are added to the set of interpolation points Interpolation_P_Vec3; at this time, the elevation values of the vertices of the second differentiable rectangular blocks inside the set of interpolation points Interpolation_P_Vec3 are all 0, while the boundary points of the Feature object are the true values.

[0050] (3.33) Using the elevation values of the intersections in the set of interpolation points, the elevation values of the vertices in the set of interpolation points are interpolated to obtain the target set of interpolation points.

[0051] In specific implementation, all points in the set of interpolation points Interpolation_P_Vec3 are recursively interpolated. Based on nearest neighbor interpolation, each point with an elevation value of 0 finds the 3 points with non-zero elevation values that are closest in the plane and calculates the elevation mean value as the elevation value of this point, so as to obtain the target set of interpolation points Interpolation_P_Vec3, and the target set of interpolation points Interpolation_P_Vec3 includes the elevation value corresponding to each point.

[0052] (3.34) Generate an interpolation triangular mesh corresponding to the interpolation region vector based on the set of target interpolation points.

[0053] In specific implementation, finally, the points in the set of target interpolation points Interpolation_P_Vec3 are used to generate an interpolation triangular mesh Node by point-by-point insertion method based on the triangular mesh. This interpolation triangular mesh Node is used to replace the Data within the range of the object feature Feature at this time and participate in the subsequent calculation of earthwork excavation and filling volume, so as to eliminate the influence of interference objects on elevation value taking; the interpolation triangular mesh Node is saved to the set Interpolation_Map<id,Node> according to the id of the object feature Feature.

[0054] (3.4) Based on the first differentiable rectangular block and the interpolation triangular mesh corresponding to the interpolation region vector, combined with the pre - stage 3D model and the post - stage 3D model within the virtual camera's field of view, determine the set of earthwork excavation volume and the set of earthwork filling volume corresponding to the target mining area. Specifically, the following operations are performed for any first differentiable rectangular block: (3.41) When the central coordinate of this first differentiable rectangular block intersects with the interpolation region vector, based on the label carried by the interpolation region vector, use the interpolation triangular mesh corresponding to the intersecting interpolation region vector to update the pre - stage 3D model or the post - stage 3D model within the virtual camera's field of view.

[0055] In specific implementation, use the central point coordinates center[x,y] of M*N first differentiable rectangular blocks as plane coordinates to calculate whether they intersect with the object feature Feature in the interpolation region vector V2. If they intersect, find the corresponding interpolation triangular mesh Node as Target_Data from the set Interpolation_Map according to the id of the object feature Feature, and determine whether Target_Data replaces the pre - stage 3D model Data_pre or the post - stage 3D model Data_last to participate in the calculation according to the value of the attribute phase (i.e., the label).

[0056] In one case, if the label indicates that this interpolation region vector belongs to before earthwork excavation and filling, use the interpolation triangular mesh corresponding to the intersecting interpolation region vector to replace the part corresponding to the interpolation region vector in the pre - stage 3D model Data_pre within the virtual camera's field of view.

[0057] In another case, if the label indicates that this interpolation region vector belongs to after earthwork excavation and filling, use the interpolation triangular mesh corresponding to the intersecting interpolation region vector to replace the part corresponding to the interpolation region vector in the post - stage 3D model Data_last within the virtual camera's field of view.

[0058] (3.42) Determine the perpendicular line passing through the center coordinates of the first differentiable rectangular block, and respectively find the intersection points between this perpendicular line and the updated previous 3D model, as well as the intersection points between this perpendicular line and the updated subsequent 3D model, so as to determine the volume difference corresponding to the first differentiable rectangular block.

[0059] In specific implementation, construct a vertical line segment L2 with the center point coordinates center of the first differentiable rectangular block. The starting point of the vertical line segment L2 is L2_P1[coor[x], coor[y], re_height + 10000], and the ending point is L2_P2[coor[x], coor[y], re_height - 10000]; through intersection calculation, obtain the intersection point Intersect_pre[x, y, z] with the previous 3D model Data_pre and the intersection point Intersect_last[x, y, z] with the subsequent 3D model Data_last; calculate the volume difference v_dis between the two-phase 3D models of the first differentiable rectangular block at this time, where v_dis = (Intersect_pre[z] - Intersect_last[z]) * width * width.

[0060] (3.43)Based on the positivity or negativity of the volume difference, save the volume difference to the earthwork excavation volume set or the earthwork filling volume set.

[0061] In specific implementation, if the volume difference v_dis > 0, then save this value to the earthwork excavation volume set W_vec and accumulate it to the total earthwork excavation volume value W_sum; if the volume difference v_dis < 0, then save this value to the earthwork filling volume set T_vec and accumulate it to the total earthwork filling volume value T_sum.

[0062] Finally, output the result to the console or to a csv format file as needed.

[0063] (IV)3D rendering and display, refer to Figure 5 The flow schematic diagram of a 3D rendering and display shown, which includes operations such as performing range distribution statistics and color band color calculation based on the earthwork excavation and filling volumes to obtain the earthwork excavation and filling volume rendering results. Considering that in actual work, simply outputting the total earthwork excavation and filling volumes cannot well determine and analyze the earthwork excavation and filling volume problems at key points and the overall distribution of the actual earthwork excavation and filling volumes, so this step renders and draws the earthwork excavation and filling volume values calculated by the previous differential calculation in a 3D space. In specific implementation, it includes the following (4.1) to (4.4): (4.1)Determine the maximum earthwork excavation volume value and the minimum earthwork excavation volume value in the earthwork excavation volume set, and determine the maximum earthwork filling volume value and the minimum earthwork filling volume value in the earthwork filling volume set.

[0064] In specific implementation, the maximum and minimum values are respectively found for the set W_vec of cyclic earth excavation volumes and the set T_vec of earth filling volumes in the excavation and filling volume set, including: the minimum earth excavation volume value W_min, the maximum earth excavation volume value W_max, the minimum earth filling volume value T_min, and the maximum earth filling volume value T_max.

[0065] (4.2)Divide the specified color strip into a first sub-color strip and a second sub-color strip.

[0066] In specific implementation, Turbo color strip is used for coloring and rendering. The length of the Turbo color strip is 256, with darker colors at both ends and lighter colors in the middle. The excavation rendering is obtained from the first 128 colors of the color strip (i.e., the first sub-color strip). The larger the excavation value, the darker the color, and the smaller the color strip index value. The filling rendering is obtained from the last 128 colors of the color strip (i.e., the second sub-color strip). The larger the filling value, the darker the color, and the larger the color strip index value.

[0067] (4.3)Determine the rendering step length of the excavation based on the maximum earth excavation volume value and the minimum earth excavation volume value. Based on the rendering step length of the excavation, determine the mapping relationship between the earth excavation volume value in the set of earth excavation volumes and the color strip index in the first sub-color strip; and, determine the rendering step length of the filling based on the maximum earth filling volume value and the minimum earth filling volume value. Based on the rendering step length of the filling, determine the mapping relationship between the earth filling volume value in the set of earth filling volumes and the color strip index in the second sub-color strip.

[0068] In specific implementation, calculate the rendering step length of the excavation W_step = (W_max - W_min) / 128, and calculate the rendering step length of the filling T_step = (T_max - T_min) / 128. The actual rendering color of the excavation is obtained by getting the current excavation value W_Value through the set W_vec of cyclic earth excavation volumes, calculating the rendering color strip index W_color_index = 127 - int((W_Value - W_min) / W_step), and then obtaining the excavation color W_color = Turbo[W_color_index]; the actual rendering color of the filling is obtained by getting the current filling value T_Value through the set T_vec of cyclic earth filling volumes, calculating the rendering color strip index T_color_index = 128 + int((T_Value - T_min) / T_step), and then obtaining the filling color T_color = Turbo[T_color_index].

[0069] (4.4)Perform rendering and drawing based on the mapping relationship to obtain the rendering result of the excavation and filling volumes corresponding to the target mining area.

[0070] In specific implementation, a rendering result of the earthwork excavation and filling volume is created in a three-dimensional space. The overall earthwork excavation and filling volume situation is rendered by using the intersection points of the front and rear periods, the differential side length width, and the current color W_color or T_color to draw a three-dimensional cube.

[0071] An embodiment of the present invention provides a specific application example for calculating the three-dimensional earthwork volume in a coal mining area based on UAV oblique data: First, the experimental area is about 1.6 square kilometers. A CW-25E fixed-wing UAV is used, equipped with a CA504R full-frame five-lens oblique aerial camera. The resolution of a single camera reaches 61 million pixels, and the total resolution reaches 305 million pixels. In the case of no ground control points, the ground resolution of the CA504R is as low as 1.5 cm, and a high-precision three-dimensional model within 10 cm can be generated. After planning the flight route and setting relevant flight parameters in the ground station, the UAV automatically flies to collect data and monitors the UAV status in real time. The resulting data includes the photos taken by five lenses and the pose data of the down-looking lens. The embodiment of the present invention uses domestic GodWork software for real-scene three-dimensional reconstruction and DOM output. Among them, the time for the previous three-dimensional reconstruction is about 23 hours, and the time for the later three-dimensional reconstruction is about 25 hours. After the reconstruction is completed, the height difference is loaded and compared for the resulting three-dimensional data, and the roads of the two-phase data are adjusted to the same height position by fine-tuning the height value of the offset matrix in the three-dimensional data.

[0072] Then, the embodiment of the present invention directly uses the DOM data to collect the target area vector and the interpolation area vector, creates a shape vector using ArcMap and draws the vector area according to requirements. Since the vector result at this time is two-dimensional, a default unified height needs to be initialized when loaded into the three-dimensional space.

[0073] Next, load the front and rear three-dimensional models, the target area vector, and the interpolation area vector into the three-dimensional space. First, calculate and adjust the viewing position of the virtual camera to ensure that the overall situation of the current target area vector can be observed. Then calculate the interpolation area vector to fit the interpolation triangular mesh, and finally calculate the actual excavation and filling results according to the differentiable rectangular block. Among them, the excavation volume value is 2219.831050, and the filling volume value is 2205.940127.

[0074] Finally, use the Turbo color ribbon to uniformly render according to the excavation and filling results. At the same time, close the nodes showing the front and rear three-dimensional data and vector data, and only display the rendering effect of the excavation and filling calculation results, so that the distribution of the excavation and filling results can be intuitively observed.

[0075] On the basis of the foregoing embodiments, an embodiment of the present invention provides a device for calculating the three-dimensional earthwork volume in a coal mining area based on UAV oblique data. See Figure 6The structural schematic diagram of a three-dimensional coal mine area earthwork calculation device based on UAV tilt data is shown. The device mainly includes the following parts: A data acquisition module 602, configured to obtain a pre-construction three-dimensional model and its corresponding pre-construction DOM data, a post-construction three-dimensional model and its corresponding post-construction DOM data of a target mining area based on UAV tilt data before and after earth filling and excavation; A vector extraction module 604, configured to extract a target area vector and an interpolation area vector corresponding to the target mining area based on the pre-construction DOM data and the post-construction DOM data. The target area vector is the area where the earth filling and excavation volume is to be calculated, and the interpolation area vector is the sub-area with ground obstacles in the area where the earth filling and excavation volume is to be calculated; An earthwork calculation module 606, configured to perform differentiable block calculation of the earthwork volume based on the target area vector and the interpolation area vector, in combination with the pre-construction three-dimensional model and the post-construction three-dimensional model, to obtain an excavation earthwork volume set and a filling earthwork volume set corresponding to the target mining area; An earthwork rendering module 608, configured to perform rendering drawing according to the excavation earthwork volume set and the filling earthwork volume set to obtain an excavation and filling earthwork volume rendering result corresponding to the target mining area.

[0076] The three-dimensional coal mine area earthwork calculation device based on UAV tilt data provided by the embodiments of the present invention can quickly and efficiently acquire and process data based on the UAV tilt modeling scheme. Compared with the traditional on-site measurement scheme and other calculation methods, the two-dimensional result display is transferred to the three-dimensional model. The present invention improves the controllability of the calculation scale based on the pre- and post-construction three-dimensional models. The interpolation area vector solves the problem of the influence of obstacles, realizes the visual rendering of the calculation result of the earth filling and excavation volume, and more efficiently and intuitively reflects the calculation scale, process and final result. Finally, it effectively improves the planning and management level of the coal mine area, enhances cost control and economic benefit evaluation, provides strong support for the audit work of the mining area, etc., and promotes the innovative application of UAV mapping technology in the coal mine industry.

[0077] In an implementation manner, the earthwork calculation module 606 is specifically configured to: Determine the virtual camera pose according to the target area vector, and control the virtual camera to adjust its pose according to the virtual camera pose so that the front of the virtual camera faces the pre-construction three-dimensional model and the post-construction three-dimensional model; Divide the target area vector into multiple first differentiable rectangular blocks; Perform elevation differentiable interpolation on the interpolation area vector to generate an interpolation triangular mesh corresponding to the interpolation area vector; Based on the first differentiable rectangular blocks and the interpolation triangular mesh corresponding to the interpolation area vector, in combination with the pre-construction three-dimensional model and the post-construction three-dimensional model within the field of view of the virtual camera, determine the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area.

[0078] In one implementation, the virtual camera pose includes the camera position coordinates and the camera rotation angle; specifically, the earthwork calculation module 606 is configured to: Determine the minimum bounding rectangle corresponding to the target area vector; Use the center coordinates of the minimum bounding rectangle as the plane coordinates of the virtual camera; and obtain the height coordinates of the virtual camera based on the intersection points of the perpendicular line passing through the center coordinates with the pre - stage 3D model or the post - stage 3D model; the plane coordinates and the height coordinates form the camera position coordinates corresponding to the virtual camera; Determine the camera rotation angle corresponding to the virtual camera based on the included angle of the long - side vector of the minimum bounding rectangle in the Cartesian coordinate system.

[0079] In one implementation, the interpolation area vector carries a label, which is used to indicate whether the interpolation area vector belongs to before or after earth filling and excavation; specifically, the earthwork calculation module 606 is configured to: For each boundary point in the boundary point set corresponding to the interpolation area vector, based on the label carried by the interpolation area vector, obtain the intersection points between the perpendicular line passing through the boundary point and the pre - stage 3D model or the post - stage 3D model, so as to generate an interpolation point set, and the elevation values of the intersection points in the interpolation point set are the same as the elevation values of their corresponding boundary points; Divide the interpolation area vector into multiple second - differentiable rectangular blocks. When the vertices of the second - differentiable rectangular block fall within the interpolation area vector, add the vertices of the second - differentiable rectangular block to the interpolation point set, and the elevation values of the vertices in the interpolation point set are 0; Interpolate the elevation values of the vertices in the interpolation point set by using the elevation values of the intersection points in the interpolation point set to obtain the target interpolation point set; Generate an interpolation triangular mesh corresponding to the interpolation area vector based on the target interpolation point set.

[0080] In one implementation, the earthwork calculation module 606 is configured to: Perform the following operations on any first - differentiable rectangular block: When the center coordinates of the first - differentiable rectangular block intersect with the interpolation area vector, based on the label carried by the interpolation area vector, use the interpolation triangular mesh corresponding to the intersecting interpolation area vector to update the pre - stage 3D model or the post - stage 3D model within the virtual camera's field of view; Determine the intersection points between the perpendicular line passing through the center coordinates of the first - differentiable rectangular block and the updated pre - stage 3D model and the updated post - stage 3D model respectively, so as to determine the volume difference corresponding to the first - differentiable rectangular block; Save the volume difference to the earth - excavation volume set or the earth - filling volume set based on the positivity or negativity of the volume difference.

[0081] In one embodiment, the earthwork calculation module 606 is specifically configured to: If the label indicates that the interpolated area vector belongs to before the filling and excavation, use the interpolated triangulation corresponding to the intersecting interpolated area vector to replace the part corresponding to the interpolated area vector in the previous three-dimensional model within the virtual camera's field of view; If the label indicates that the interpolated area vector belongs to after the filling and excavation, use the interpolated triangulation corresponding to the intersecting interpolated area vector to replace the part corresponding to the interpolated area vector in the later three-dimensional model within the virtual camera's field of view.

[0082] In one embodiment, the earthwork rendering module 608 is specifically configured to: Determine the maximum earthwork excavation value and the minimum earthwork excavation value in the earthwork excavation set, and determine the maximum earthwork filling value and the minimum earthwork filling value in the earthwork filling set; Divide the specified color strip into a first sub-color strip and a second sub-color strip; Determine the rendering step length of the excavation based on the maximum earthwork excavation value and the minimum earthwork excavation value, and based on the rendering step length of the excavation, determine the mapping relationship between the earthwork excavation values in the earthwork excavation set and the color strip indices in the first sub-color strip; and, determine the rendering step length of the filling based on the maximum earthwork filling value and the minimum earthwork filling value, and based on the rendering step length of the filling, determine the mapping relationship between the earthwork filling values in the earthwork filling set and the color strip indices in the second sub-color strip; Perform rendering drawing based on the mapping relationship to obtain the rendering result of the excavation and filling earthwork corresponding to the target mining area.

[0083] In one embodiment, the data acquisition module 602 is specifically configured to: Determine the same reference ground feature point and its corresponding previous elevation value and later elevation value from the previous three-dimensional model and the later three-dimensional model; Determine the offset matrix based on the previous elevation value and the later elevation value corresponding to the reference ground feature point; Fine-tune the previous three-dimensional model and the later three-dimensional model using the offset matrix so that the previous elevation value corresponding to the same reference ground feature point coincides with the later elevation value.

[0084] For the device provided by the embodiments of the present invention, its implementation principle and the technical effects generated are the same as those of the foregoing method embodiments. For the sake of brief description, for the parts not mentioned in the device embodiments, reference may be made to the corresponding content in the foregoing method embodiments.

[0085] The embodiments of the present invention provide an electronic device. Specifically, the electronic device includes a processor and a memory; a computer program is stored on the memory, and when the computer program is run by the processor, it executes the method according to any one of the foregoing embodiments.

[0086] Figure 7 A structural schematic diagram of an electronic device provided by an embodiment of the present invention. The electronic device 100 includes: a processor 70, a memory 71, a bus 72, and a communication interface 73. The processor 70, the communication interface 73, and the memory 71 are connected through the bus 72. The processor 70 is configured to execute an executable module stored in the memory 71, such as a computer program.

[0087] Among them, the memory 71 may include a high-speed random access memory (RAM), and may also include a non-volatile memory, such as at least one disk memory. Through at least one communication interface 73 (which can be wired or wireless), a communication connection is established between this system network element and at least one other network element. The Internet, wide area network, local area network, metropolitan area network, etc. can be used.

[0088] The bus 72 may be an ISA bus, a PCI bus, an EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 7 only a bidirectional arrow is used in the figure, but it does not mean that there is only one bus or one type of bus.

[0089] Among them, the memory 71 is used to store a program. After receiving an execution instruction, the processor 70 executes the program. The method executed by the device defined by the flow process disclosed in any embodiment of the foregoing embodiments of the present invention can be applied to the processor 70 or implemented by the processor 70.

[0090] The processor 70 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the integrated logic circuit of the hardware in the processor 70 or the instructions in the form of software. The above-mentioned processor 70 may be a general-purpose processor, including a central processing unit (CPU for short), a network processor (NP for short), etc.; it may also be a digital signal processor (DSP for short), an application specific integrated circuit (ASIC for short), a field-programmable gate array (FPGA for short), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in combination with the embodiments of the present invention can be directly embodied as being executed and completed by a hardware decoding processor, or executed and completed by a combination of the hardware and software modules in the decoding processor. The software module may be located in a mature storage medium in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. This storage medium is located in the memory 71, and the processor 70 reads the information in the memory 71 and combines its hardware to complete the steps of the above method.

[0091] The computer program product of the readable storage medium provided by the embodiments of the present invention includes a computer-readable storage medium storing program code, and the instructions included in the program code can be used to execute the methods described in the foregoing method embodiments. For specific implementation, reference can be made to the foregoing method embodiments and will not be elaborated herein.

[0092] If the above-described functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0093] Finally, it should be noted that the above-described embodiments are only specific embodiments of the present invention, used to illustrate the technical solutions of the present invention, rather than limiting them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the technical field can still modify the technical solutions described in the foregoing embodiments, or can easily conceive of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes, or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims

1. A three-dimensional coal mine earthwork calculation method based on drone oblique data, characterized in that, Including: Obtaining a pre - excavation and filling 3D model of the target mining area before and after excavation and filling, its corresponding pre - period DOM data, a post - period 3D model, and its corresponding post - period DOM data based on UAV tilt data; Based on the pre - period DOM data and the post - period DOM data, extracting the target area vector and the interpolation area vector corresponding to the target mining area, where the target area vector is the area for calculating the excavation and filling earthwork volume, and the interpolation area vector is the sub - area with ground interference objects within the area for calculating the excavation and filling earthwork volume; Based on the target area vector and the interpolation area vector, combining the pre - period 3D model and the post - period 3D model, performing differential block calculation of the earthwork volume to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area; Rendering and drawing according to the excavation earthwork volume set and the filling earthwork volume set to obtain the rendering result of the excavation and filling earthwork volume corresponding to the target mining area.

2. The three-dimensional coal mine earthwork calculation method based on UAV tilt data according to claim 1, characterized in that, Based on the target area vector and the interpolation area vector, combining the pre - period 3D model and the post - period 3D model, performing differential block calculation of the earthwork volume to obtain the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area, including: Determining the virtual camera pose according to the target area vector, and controlling the virtual camera to adjust its pose according to the virtual camera pose so that the front of the virtual camera faces the pre - period 3D model and the post - period 3D model; Dividing the target area vector into multiple first differentiable rectangular sub - blocks; Performing elevation - differentiable interpolation on the interpolation area vector to generate an interpolation triangular network corresponding to the interpolation area vector; Based on the first differentiable rectangular sub - blocks and the interpolation triangular network corresponding to the interpolation area vector, combining the pre - period 3D model and the post - period 3D model within the field of view of the virtual camera to determine the excavation earthwork volume set and the filling earthwork volume set corresponding to the target mining area.

3. The three-dimensional coal mine area earthwork calculation method based on drone tilt data according to claim 2, characterized in that, The virtual camera pose includes the camera position coordinates and the camera rotation angle; determining the virtual camera pose according to the target area vector includes: Determining the minimum circumscribed rectangle corresponding to the target area vector; Taking the center coordinates of the minimum circumscribed rectangle as the plane coordinates of the virtual camera; and obtaining the height coordinates of the virtual camera based on the intersection point of the perpendicular line passing through the center coordinates and the pre - period 3D model or the post - period 3D model; the plane coordinates and the height coordinates form the camera position coordinates corresponding to the virtual camera; Based on the included angle of the long - side vector of the minimum circumscribed rectangle in the Cartesian coordinate system, determining the camera rotation angle corresponding to the virtual camera.

4. The three-dimensional coal mine area earthwork calculation method based on UAV tilt data according to claim 2, wherein The interpolation area vector carries a label, and the label is used to represent whether the interpolation area vector belongs to before or after excavation and filling; performing elevation - differentiable interpolation on the interpolation area vector to generate an interpolation triangular network corresponding to the interpolation area vector includes: For each boundary point in the set of boundary points corresponding to the interpolation region vector, based on the label carried by the interpolation region vector, obtain the intersection points between the vertical line drawn through the boundary point and the previous 3D model or the later 3D model, so as to generate an interpolation point set, where the elevation value of the intersection point in the interpolation point set is the same as the elevation value of the corresponding boundary point; Divide the interpolation region vector into multiple second differentiable rectangular blocks. When the vertices of the second differentiable rectangular block fall within the interpolation region vector, add the vertices of the second differentiable rectangular block to the interpolation point set, and the elevation value of the vertex in the interpolation point set is 0; Use the elevation values of the intersection points in the interpolation point set to interpolate the elevation values of the vertices in the interpolation point set to obtain a target interpolation point set; Generate an interpolation triangular network corresponding to the interpolation region vector based on the target interpolation point set.

5. The method for calculating the earthwork volume of a three-dimensional coal mining area based on the tilt data of an unmanned aerial vehicle according to claim 4, wherein Based on the first differentiable rectangular block and the interpolation triangular network corresponding to the interpolation region vector, combine the previous 3D model and the later 3D model within the virtual camera's field of view to determine the earthwork excavation volume set and earthwork filling volume set corresponding to the target mining area, including: Perform the following operations for any one of the first differentiable rectangular blocks: When the central coordinate of the first differentiable rectangular block intersects with the interpolation region vector, based on the label carried by the interpolation region vector, use the interpolation triangular network corresponding to the intersecting interpolation region vector to update the previous 3D model or the later 3D model within the virtual camera's field of view; Determine the intersection points between the perpendicular line passing through the central coordinate of the first differentiable rectangular block and the updated previous 3D model and the updated later 3D model respectively, so as to determine the volume difference corresponding to the first differentiable rectangular block; Based on the positivity or negativity of the volume difference, save the volume difference to the earthwork excavation volume set or the earthwork filling volume set.

6. The three-dimensional coal mine area earthwork calculation method based on drone tilt data according to claim 5, wherein, Based on the label carried by the interpolation region vector, use the interpolation triangular network corresponding to the intersecting interpolation region vector to update the previous 3D model or the later 3D model within the virtual camera's field of view, including: If the label indicates that the interpolation region vector belongs to before earthwork excavation and filling, use the interpolation triangular network corresponding to the intersecting interpolation region vector to replace the part corresponding to the interpolation region vector in the previous 3D model within the virtual camera's field of view; If the label indicates that the interpolation region vector belongs to after earthwork excavation and filling, use the interpolation triangular network corresponding to the intersecting interpolation region vector to replace the part corresponding to the interpolation region vector in the later 3D model within the virtual camera's field of view.

7. The three-dimensional coal mine area earthwork calculation method based on the tilt data of the unmanned aerial vehicle according to claim 5, characterized in that, Perform rendering based on the earthwork excavation volume set and the earthwork filling volume set to obtain the earthwork excavation and filling volume rendering result corresponding to the target mining area, including: Determine the maximum earthwork excavation volume value and the minimum earthwork excavation volume value in the earthwork excavation volume set, and determine the maximum earthwork filling volume value and the minimum earthwork filling volume value in the earthwork filling volume set; Divide the specified color band into a first sub-color band and a second sub-color band; Determine the rendering step length of the excavation based on the maximum excavation volume value and the minimum excavation volume value. Based on the rendering step length of the excavation, determine the mapping relationship between the excavation volume values in the excavation volume set and the color band indexes in the first sub-color band; and, determine the rendering step length of the filling based on the maximum filling volume value and the minimum filling volume value. Based on the rendering step length of the filling, determine the mapping relationship between the filling volume values in the filling volume set and the color band indexes in the second sub-color band; Perform rendering based on the mapping relationship to obtain the excavation and filling volume rendering result corresponding to the target mining area.

8. The method for calculating the three-dimensional earthwork volume of a coal mine area based on the drone tilt data according to claim 1, characterized in that, After obtaining the pre-excavation and filling pre-3D model of the target mining area and its corresponding pre-DOM data, and the post-excavation and filling post-3D model and its corresponding post-DOM data based on the UAV oblique data, the method further includes: Determine the same reference ground feature point and its corresponding pre-elevation value and post-elevation value from the pre-3D model and the post-3D model; Determine the offset matrix based on the pre-elevation value and the post-elevation value corresponding to the reference ground feature point; Use the offset matrix to fine-tune the pre-3D model and the post-3D model so that the pre-elevation value corresponding to the same reference ground feature point coincides with the post-elevation value.

9. A three-dimensional coal mine earthwork calculation device based on UAV tilt data, characterized in that, Includes: A data acquisition module for obtaining the pre-excavation and filling pre-3D model of the target mining area and its corresponding pre-DOM data, and the post-excavation and filling post-3D model and its corresponding post-DOM data based on the UAV oblique data; A vector extraction module for extracting the target area vector and the interpolation area vector corresponding to the target mining area based on the pre-DOM data and the post-DOM data. The target area vector is the area where the excavation and filling volume needs to be calculated, and the interpolation area vector is the sub-area with ground interference objects in the area where the excavation and filling volume needs to be calculated; An earthwork calculation module for performing differential block calculation of the earthwork volume based on the target area vector and the interpolation area vector, in combination with the pre-3D model and the post-3D model, to obtain the excavation volume set and the filling volume set corresponding to the target mining area; An earthwork rendering module for performing rendering based on the excavation volume set and the filling volume set to obtain the excavation and filling volume rendering result corresponding to the target mining area.

10. An electronic device, characterized in that, Includes a processor and a memory. The memory stores computer-executable instructions that can be executed by the processor. The processor executes the computer-executable instructions to implement the method according to any one of claims 1 to 8.

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