Earthwork excavation construction methods in landslide control using 3D oblique photography

Abstract

This invention provides a method for earthwork excavation in landslide control using 3D oblique photography. The method involves obtaining 3D topographic data of the landslide site through UAV-based oblique photography during landslide clearing and treatment. A 3D model is then reconstructed and spatial coordinates are registered on an indoor data processing terminal. The 3D coordinate data of the landslide feature surfaces are combined with the 3D model to form a construction space domain. The coordinate data within this domain is input into a vehicle-mounted data processing terminal. This coordinate data, along with a vehicle-mounted positioning system, guides the vehicle's operation. Simultaneously, the vehicle-mounted positioning system generates alarm feedback for operations outside the construction domain, correcting the vehicle's maneuvers. This invention can be used to guide precise digital construction of landslide control and earthwork, controlling the morphology of earthwork and the application of 3D data results.

Description

Technical Field

[0001] This invention patent relates to the field of landslide control engineering construction, specifically to a method for earthwork excavation in landslide control using three-dimensional oblique photography. The method mainly utilizes three-dimensional oblique photography for precise digital control of earthwork excavation in landslides. This method is suitable for precise construction control when multiple surfaces are combined to form a fixed excavation shape. Background Technology

[0002] After a landslide occurs, a fault zone will be formed through at least one surface within the rock and soil mass. Especially in rock slopes, landslides often slide along an unfavorable combination of one or more structural surfaces. Whether it is the crack at the rear edge of the landslide, the fault surface at the side edge of the landslide, or the shear exit location at the front edge of the landslide, they all show certain regularities. These regularities can be obtained through manual investigation to grasp their basic information, including the attitude of the sliding surface, that is, the dip, strike, and dip angle of the structural surface (slip surface). In real-world engineering projects, especially after a landslide, it is necessary to remove the landslide mass. Without a clear understanding of the landslide surface, accurate manual excavation is impossible. Even when the landslide surface is clear, it is difficult to construct along its location, hindering accurate removal. Excessive removal of the landslide mass alters the original stress balance, causing the design to fail to match the site conditions. Changes in design conditions can easily lead to secondary landslides and other hazards. Incomplete removal of the landslide mass poses an even greater risk, increasing residual sliding forces beyond the design specifications, reducing the slope safety factor after implementation, failing to meet code requirements, and potentially leading to further sliding while increasing construction risks. Therefore, accurate earthwork removal is of paramount importance.

[0003] In the conventional slope excavation method, the top line, ramp platform, and toe line of the slope are marked out on the construction site. The excavation of each slope level above and below the ramp platform relies entirely on the experience and skill of the machinery operators. This results in the inaccurate correspondence between the plane positions of different elevation points on the slope, often leading to situations where a slope is gentle at the top and steep at the bottom, or steep at the top and gentle at the bottom. This is very detrimental to the stability of the slope after excavation. Therefore, controlling the precise excavation face is of practical importance and significance. Summary of the Invention

[0004] To reduce the blind spots of manual operations and improve the precision of earthwork operations, especially the precise control of earthwork excavation in slope and landslide areas, and to ensure safety during construction, this invention provides a method for earthwork excavation in landslide control using three-dimensional oblique photography. This method breaks away from the traditional approach of completely manual control of the excavation pattern. It introduces three-dimensional oblique photography to model the terrain, calculates the overlap of spatial structural surfaces to establish an excavation model, and uses this as the excavation target data. This data is then imported into an onboard information segment to guide the operation of machinery. The real-time positioning feedback error signals from the machinery are used to adjust the excavation actions, forming a closed loop of early warning and alarm, thus achieving precise excavation.

[0005] To achieve the above objectives, this invention provides a method for earthwork excavation in landslide control using three-dimensional oblique photography. The specific steps of the method are as follows:

[0006] (1) Before construction, use drones to conduct three-dimensional oblique photography of the construction area to be excavated, and collect images from different angles simultaneously along the designated route to obtain high-precision location features of the original terrain of the construction area to be excavated. The three-dimensional image data of the aerial photography is used to form a three-dimensional spatial coordinate model of the three-dimensional oblique photography. The three-dimensional spatial model under the construction coordinate system is obtained by matching the fixed point construction coordinate system collected on site with the corresponding point coordinates in the three-dimensional spatial coordinate model.

[0007] (2) Identify the slope slip surface based on the high-definition image taken by the UAV in step (1), pick at least three spatial coordinates of the slope slip surface in the three-dimensional spatial model under the construction coordinate system in step (1), calculate the intersection of the multiple slip surface spatial extension surfaces, form a closed spatial domain by the intersection of the ground surface and the multiple slip surfaces, and use all the spatial coordinate sets in this closed spatial domain as the early warning coordinate set to access the vehicle data processing terminal for use as the range of real-time coordinate feedback early warning during construction.

[0008] (3) A vehicle-mounted excavation positioning module is fixed on the mechanical bucket. The excavation work surface is located by using the relationship between the GPS satellite positioning system, the fixed signal base station on site and the vehicle-mounted excavation positioning module. This positioning data is sent in real time to the vehicle-mounted data processing terminal that accesses the warning coordinate set in step (2). The vehicle-mounted data processing terminal compares the received real-time excavation positioning coordinates with the warning coordinate set to form a warning feedback. When the construction area formed by the warning coordinate set is exceeded, an alarm is issued to correct the mechanical operation direction and work in the correct construction area.

[0009] A further technical solution of the present invention: In step (1), the high-precision position of the original terrain of the construction area to be excavated obtained by three-dimensional oblique photography to form a three-dimensional spatial coordinate model is specifically achieved by using three-dimensional oblique photography modeling technology to import high-definition images from different angles of the UAV into commercial processing software to quickly form a three-dimensional model and export an editable three-dimensional spatial coordinate model.

[0010] A further technical solution of the present invention: The process of forming a three-dimensional spatial model under the precise construction coordinate system in step (1) is as follows: by collecting the coordinates of at least three fixed points in the construction coordinate system on site, calculating and marking the corresponding point coordinates of at least three fixed points in the three-dimensional spatial coordinate model of the three-dimensional oblique photography, and performing rotation and translation operations on the three-dimensional spatial coordinate model of the three-dimensional oblique photography so that the coordinates of at least three fixed points in the construction coordinate system are precisely matched with the coordinates in the three-dimensional spatial coordinate model, thereby obtaining a three-dimensional spatial model under the construction coordinate system.

[0011] A further technical solution of the present invention: The specific process of calculating the spatial extension and intersection position of the multiple sliding surfaces in step (2) is as follows: After identifying the first landslide surface, take the coordinates of three points on the plane in the three-dimensional spatial model under the precise construction coordinate system, which are X1, X2, and X3, respectively: (x 11 x 12 x 13 ), (x 21 x 22 x 23 ), (x 31 x 32 x 33) These three points determine a unique spatial plane P1, and also determine the normal vector of plane P1. Similarly, take the coordinates of three points Y1(y) on the sliding surface of the second landslide. 11 ,y 12 ,y 13 ), Y2(y 21 ,y 22 ,y 23 ), Y3(y 31 ,y 32 ,y 33) These three points determine a unique spatial plane P2, and also determine the normal vector of plane P2. Using the coordinates of three points and the normal vector, the equation of the spatial plane can be obtained as follows:

[0012] f i (x,y,z)=e i1 (xx i1 ,)+e i2 (yx i2 ,)+e i3 (zxi3 ,)=0,

[0013] By solving the equations of any two spatial planes simultaneously, we can obtain the equation of the line of intersection of the two spatial planes:

[0014]

[0015] Based on the position of the intersection of two spatial planes superimposed on the three-dimensional spatial model under the construction coordinate system, the coordinates of the closed area from the intersection of the two spatial planes to the surface of the three-dimensional spatial model can be picked to form the spatial domain coordinate set Ω(x,y,z). All coordinate points in this coordinate set are identified as the range of soil and rock that needs to be removed. This coordinate set is input into the vehicle information terminal as the discrimination standard.

[0016] A further technical solution of the present invention: In step (1), the principle of calculating the coordinates of the fixed point in the three-dimensional spatial coordinate model of the three-dimensional oblique photography by collecting the coordinates of the fixed point in the construction coordinate system on site adopts the transformation of the spatial rectangular coordinate system. The specific process is as follows:

[0017] Three coordinate points M1(m) are taken in the on-site construction coordinate system. 11 ,m 12 ,m 13 M2(m) 21 ,m 22 ,m 23 M3(m) 31 ,m 32 ,m 33 In the three-dimensional spatial coordinate model of three-dimensional oblique photography, three coordinate points N1(n) are taken. 11 ,n 12 ,n 13 ), N2(n 21 ,n 22 ,n 23 ), N3(n 31 ,n 32 ,n 33 And establish the following transformation relationship:

[0018]

[0019] The matrix T used for coordinate transformation can be calculated:

[0020] T = M × N -1

[0021] Where T is the transformation matrix; N -1 M is the inverse matrix of N; M is the coordinate matrix of three points in the on-site construction coordinate system; N is the coordinate matrix of three points in the three-dimensional spatial coordinate model.

[0022] Once the coordinate transformation matrix T is calculated, the coordinates L(l1, l2, l3) of any coordinate point K(k1, k2, k3) in the three-dimensional spatial model corresponding to any coordinate point K(k1, k2, k3) in the construction site coordinate system can be calculated using the following formula:

[0023]

[0024] Where K is a matrix composed of the coordinates of a point in the on-site construction coordinate system; L is a matrix composed of the coordinates of a point in the three-dimensional spatial coordinate model.

[0025] The preferred technical solution of this invention is as follows: The vehicle-mounted excavation positioning module is fixed on the mechanical bucket. The vehicle-mounted excavation positioning module maintains communication with the fixed signal base station and GPS navigation satellite at a certain frequency on site. It collects the coordinates of the mechanical bucket in real time and automatically inputs them into the vehicle-mounted data processing terminal. It uses the stored spatial coordinate set Ω(x,y,z) to determine whether the real-time coordinates of the mechanical bucket belong to the spatial coordinate set Ω. If they do, a warning and alarm are generated. The next step is to correct the mechanical operation and implement the excavation action within the spatial coordinate set Ω, that is, the spatial range where the excavation operation needs to be carried out.

[0026] The preferred technical solution of this invention is as follows: The fixed signal base station on site is set at a reference point with known coordinates and continuously receives all visible GPS satellite signals; the fixed signal base station on site transmits the station coordinates, pseudorange observation values, carrier phase observation values, satellite tracking status, and receiver operating status to the vehicle-mounted excavation positioning module via a wireless data link; the vehicle-mounted excavation positioning module first initializes, completes the search and solution of integer unknowns, and then enters dynamic operation. When receiving data from the fixed signal base station on site, the vehicle-mounted excavation positioning module simultaneously observes and collects GPS satellite carrier phase data, solves the carrier phase integer ambiguity through differential processing within the system, and obtains the planar coordinates x, y, and elevation h of the mobile station based on the correlation between the vehicle-mounted excavation positioning module and the fixed signal base station on site, which are the spatial point coordinates of the construction coordinate system collected on site.

[0027] A preferred technical solution of the present invention: The mechanical bucket collects real-time coordinates A1(x1, x2, x3), and the vehicle-mounted data processing terminal calculates the minimum distance L1 from point A1 to the boundary surface Ωs(x, y, z) of the spatial domain coordinate set according to the following formula:

[0028]

[0029] The warning operation is based on the relationship between the minimum distance L1 and the warning value L of the excavation boundary distance. Specifically: when 0 ≤ L1 ≤ L, a warning is issued to the operating end, and the mechanical operation reduces the corresponding movement amplitude; when 0 ≤ L1 ≤ L, a warning is issued ... When an alarm is triggered, it is sent to the control terminal, at which point the movement of the mechanical bucket in the forward direction is immediately stopped and corrected in time; the L value can be changed to adjust the slack of the operation.

[0030] A preferred technical solution of the present invention: The mechanical bucket collects real-time coordinate points A1(x1, x2, x3), the vehicle-mounted data processing terminal determines whether the warning value range has been reached, and records these coordinate points according to frequency to form a point set A. i (x1, x2, x3) are used to derive the coordinates of these point sets to form a spatial entity Ω. i The volume is calculated to represent the excavation work volume; the 3D model before excavation is used to determine the Ω... i Taking a Boolean subtraction operation yields the three-dimensional terrain model after excavation, which is the post-construction terrain coordinate set.

[0031] The beneficial effects of this invention are:

[0032] (1) High-precision three-dimensional oblique photography technology is used to collect three-dimensional terrain data, which is applied to the excavation of slopes or landslides. It can also calculate and locate the position of the sliding surface and the target clearing surface in the model. It has the advantages of being fast, accurate and efficient in the collection and application of raw data.

[0033] (2) The vehicle-mounted information terminal has the function of processing and storing three-dimensional coordinate data, comparing the excavation location data in real time and calculating the error with the target clean surface. Based on the comparison error data, it can promptly trigger early warning and alarm, guide the direction of excavation operations, and greatly reduce the blindness or error of manual operation during the excavation process.

[0034] (3) Excavation data is updated and recorded in real time to the vehicle information terminal. The final excavation domain coordinate set can be processed to obtain the excavation surface shape and excavation domain volume, that is, the final slope and excavation volume. The accurate three-dimensional model data results can be conveniently applied to project acceptance. Attached Figure Description

[0035] Figure 1 This is a flowchart of the construction control method module in this invention;

[0036] Figure 2 This is a schematic diagram illustrating the components of the construction control method in this invention.

[0037] Figure 3 This is a schematic diagram of the airborne operation feedback adjustment process in this invention;

[0038] Figure 4 This is a simplified schematic diagram of the sliding geometry in this invention.

[0039] In the diagram: 1—UAV; 2—Model data processing terminal; 3—Excavating machinery; 4—GPS satellite; 5—Field control base station; 3-1—Vehicle-mounted information processing terminal; 3-2—Machinery control console; 3-3—Vehicle-mounted excavation positioning module; 6-1—Second landslide surface; 6-2—First landslide surface; 6-3—Intersection line of the surfaces. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments. Figures 1 to 4 All accompanying drawings are simplified versions of embodiments and are intended solely for clearly and concisely illustrating the embodiments of the present invention. The specific solutions described in the embodiments of the present invention are not intended to limit the scope of the claimed invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0041] The embodiment provides a method for earthwork excavation in landslide control using three-dimensional oblique photography, and the working process is as follows: Figure 1 and Figure 2 As shown, specifically, after a landslide occurs and clearing and treatment are required, a three-dimensional oblique photography drone 1 enters the site to conduct three-dimensional oblique photography of the construction area before excavation. Images are simultaneously acquired from different perspectives along a designated flight path to obtain high-precision location features of the original terrain of the construction area. The three-dimensional image data is used to complete positioning and modeling at the model data processing terminal 2, forming a three-dimensional spatial model with registered construction coordinates. Based on the identified slope sliding surface features, the spatial coordinates of the sliding surface point set are picked, or the sliding surface location points and spatial attitude are manually specified. The spatial extension and intersection positions of multiple sliding surfaces are calculated, and the ground surface and the intersection of multiple sliding surfaces form a closed spatial domain. All spatial coordinates within this closed spatial domain are integrated into an early warning coordinate set and connected to the vehicle-mounted data processing terminal 3-1, which is used as the range for real-time coordinate feedback and early warning during construction. The vehicle-mounted excavation positioning module 3-3 is fixed on the mechanical bucket. The excavation work surface is located by using the relationship between the GPS satellite positioning system 4, the fixed signal base station 5 and the vehicle-mounted excavation positioning module 3-3. This positioning data is sent to the vehicle-mounted data processing terminal 3-1 in real time. The vehicle-mounted data processing terminal 3-1 generates early warning feedback by comparing the real-time excavation positioning coordinates. If the work area is exceeded, an alarm will be issued to correct the direction of the mechanical operation 3-2 and move the machine to the correct work area.

[0042] The embodiment provides a method for earthwork excavation in landslide control using three-dimensional oblique photography, and the specific construction steps are as follows:

[0043] Step 1: Before construction, use a drone to conduct 3D oblique photography of the construction area to be excavated. Simultaneously acquire images from different perspectives along a designated flight path to obtain high-precision location features of the original terrain of the construction area to be excavated. Using 3D oblique photography modeling technology, import the high-definition images from different angles of the drone into commercial processing software to quickly form a 3D model. The 3D spatial coordinate model includes x, y, z 3D coordinate data, and an editable 3D spatial coordinate model Ω0 is exported.

[0044] Step 2: Accurately match the construction coordinate model with the 3D spatial coordinate model. Collect at least three coordinate points in the construction coordinate system from fixed markers on-site. Then, take the corresponding point coordinates from the 3D spatial coordinate model Ω0. Perform rotation and translation operations on the 3D spatial coordinate model to accurately match the three points in the construction coordinate system with the three points in the 3D spatial coordinate model, thus obtaining a precise 3D spatial model in the construction coordinate system. The principle is based on the transformation of the spatial rectangular coordinate system, and the method is as follows:

[0045] Three coordinate points are taken in the on-site construction coordinate system:

[0046] M1(m 11 ,m 12 ,m 13 M2(m) 21 ,m 22 ,m 23 M3(m) 31 ,m 32 ,m 33 ),

[0047] In the three-dimensional spatial coordinate model of three-dimensional oblique photography, three coordinate points N1(n) are taken. 11 ,n 12 ,n 13 ), N2(n 21 ,n 22 ,n 23 ), N3(n 31 ,n 32 ,n 33 And establish the following transformation relationship:

[0048]

[0049] The matrix T used for coordinate transformation can be calculated:

[0050] T = M × N -1

[0051] Where T is the transformation matrix; N -1Let T be the inverse matrix of N; M be the coordinate matrix of three points in the on-site construction coordinate system; and N be the coordinate matrix of three points in the three-dimensional spatial coordinate model. Once the coordinate transformation matrix T is calculated, the coordinates L of any coordinate point K in the on-site coordinate system within the three-dimensional spatial model can be calculated using the following formula:

[0052]

[0053] Where K is the coordinate matrix of a point in the on-site construction coordinate system; L is the coordinate matrix of a point in the three-dimensional spatial coordinate model.

[0054] Step 3: Based on the high-definition images of the UAV aerial photography in step (1), identify the slope slip surface. In the three-dimensional spatial model under the construction coordinate system in step (1), pick at least three spatial coordinates of the slope slip surface. Calculate the intersection of the multiple slip surface spatial extension surfaces. Form a closed spatial domain by connecting the ground surface and the multiple slip surfaces. Use all the spatial coordinates within this closed spatial domain as the early warning coordinate set and connect it to the vehicle-mounted data processing terminal for use as the range of real-time coordinate feedback early warning during construction. The landslide slip surface is a geological structural surface or weak surface, with planar characteristics, especially in rock landslides. Therefore, after identifying the first landslide slip surface 6-2, take the coordinates of three points on this plane in the three-dimensional spatial model under the precise construction coordinate system, which are X1, X2, and X3, respectively: (x 11 x 12 x 13 ), (x 21 x 22 x 23 ), (x 31 x 32 x 33) ,like Figure 4 As shown, these three points can determine a unique spatial plane P1, and also determine the normal vector of plane P1. Similarly, take the coordinates of three points Y1(y) on the sliding surface 6-1 of the second landslide. 11 ,y 12 ,y 13 ), Y2(y 21 ,y 22 ,y 23 ), Y3(y 31 ,y 32 ,y 33) These three points determine a unique spatial plane P2, and also determine the normal vector of plane P2. Using the coordinates of three points and the normal vector, the equation of the spatial plane can be obtained as follows:

[0055] f i (x,y,z)=e i1 (xx i1 ,)+e i2(yx i2 ,)+e i3 (zx i3 ,)=0,

[0056] By solving the equations of any two spatial planes simultaneously, we can obtain the equation of the line of intersection of the two spatial planes:

[0057]

[0058] Based on the position of the intersection of two spatial planes superimposed on the three-dimensional spatial model under the construction coordinate system, the coordinates of the closed area from the intersection of two spatial planes to the surface of the three-dimensional spatial model can be picked to form the spatial domain coordinate set Ω1(x,y,z). All coordinate points in this coordinate set are identified as the range of soil and rock that needs to be removed. This coordinate set is input into the vehicle information terminal as the discrimination standard.

[0059] Step 4: The vehicle-mounted excavation positioning module 3-3 is fixed on the mechanical bucket. The vehicle-mounted excavation positioning module 3-3 maintains a certain frequency of communication with the on-site control base station and GPS navigation satellite. It collects the coordinates of the mechanical bucket in real time and automatically inputs them into the vehicle-mounted information terminal. It uses the stored spatial coordinate set Ω1(x,y,z) to determine whether the real-time coordinates of the mechanical bucket belong to the spatial coordinate set Ω1. If they do, a warning and alarm are generated. The next step is to correct the mechanical control panel 3-2 and implement the excavation action within the spatial coordinate set Ω1, that is, the spatial range where the excavation operation needs to be carried out.

[0060] Step 5: The field control base station 5 is set up at a reference point with known coordinates and continuously receives signals from all visible GPS satellites 4. The field control base station 5 transmits the station coordinates, pseudorange observations, carrier phase observations, satellite tracking status, and receiver operating status to the vehicle-mounted excavation positioning module 3-3 via a wireless data link. The vehicle-mounted excavation positioning module 3-3 first initializes, completes the search and solution of integer unknowns, and then enters dynamic operation. When receiving data from the field control base station 5, the vehicle-mounted excavation positioning module 3-3 simultaneously observes and collects GPS satellite 4 carrier phase data, solves the carrier phase integer ambiguity through differential processing within the system, and obtains the rover's planar coordinates x, y and elevation h based on the correlation between the vehicle-mounted excavation positioning module 3-3 and the field control base station 5, i.e., the spatial coordinates (x, y) in the field construction coordinate system. 11 ,x 12 ,x 13 ).

[0061] Step 6: The mechanical bucket collects real-time coordinates A1(x1, x2, x3), and the vehicle-mounted information terminal 3-1 calculates the minimum distance L1 from point A1 to the boundary surface Ωs(x, y, z) of the spatial domain coordinate set.

[0062]

[0063] When 0≤L1≤L, an early warning is issued to the operating terminal 3-2. At this time, the mechanical operation needs to reduce the corresponding movement amplitude. When an alarm is triggered, it is sent to the control terminal. At this time, the movement of the mechanical bucket in the forward direction must be stopped immediately and the error corrected in time. Here, L is the warning value of the excavation boundary distance. The slackness of the operation action can be adjusted by changing the value of L.

[0064] Step 7: The mechanical bucket collects real-time coordinate points A1(x1, x2, x3) to form point set A. i (x1, x2, x3) are used to derive the coordinates of these point sets to form a spatial entity Ω. i The volume is calculated to represent the excavation work volume; the 3D model before excavation is used to determine the Ω... i The Boolean subtraction operation, Ω0-Ωi, yields the three-dimensional terrain model after excavation, which is the post-construction terrain coordinate set and can be used as the basis for project acceptance.

[0065] The above description is merely one embodiment of the present invention, and while it is detailed and specific, it should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for earthwork excavation in landslide control using three-dimensional oblique photography, characterized in that, The specific steps of the construction method are as follows: (1) Before construction, use drones to conduct three-dimensional oblique photography of the construction area to be excavated, and collect images from different angles simultaneously along the designated route to obtain high-precision location features of the original terrain of the construction area to be excavated. The three-dimensional image data of the aerial photography is used to form a three-dimensional spatial coordinate model of the three-dimensional oblique photography. The three-dimensional spatial model under the construction coordinate system is obtained by matching the fixed point construction coordinate system collected on site with the corresponding point coordinates in the three-dimensional spatial coordinate model. (2) Based on the high-definition images of the UAV aerial photography in step (1), identify the slope slip surface. In the three-dimensional spatial model under the construction coordinate system in step (1), pick at least three spatial coordinates of the slope slip surface. Calculate the intersection of the multiple slip surface spatial extension surfaces. Form a closed spatial domain by intersecting the ground surface and the multiple slip surfaces. Use all the spatial coordinate sets within this closed spatial domain as the early warning coordinate set and connect it to the vehicle-mounted data processing terminal for use as the range of real-time coordinate feedback early warning during construction. The specific process of calculating the spatial extension and intersection of the multiple slip surfaces in step (2) is as follows: After identifying the first landslide slip surface, take the coordinates of three points of the first landslide slip surface as X1, X2, and X3 in the three-dimensional spatial model under the precise construction coordinate system. The coordinates are respectively: (x 11 x 12 x 13 ), (x 21 x 22 x 23 ), (x 31 x 32 x 33) The coordinates of these three points determine a unique spatial plane P1, and also determine the normal vector of plane P1. Similarly, take the coordinates of three points Y1(y) on the sliding surface of the second landslide. 11 ,y 12 ,y 13 ), Y2(y 21 ,y 22 ,y 23 ), Y3(y 31 ,y 32 ,y 33) The coordinates of these three points determine a unique spatial plane P2, and also determine the normal vector of plane P2. The equation of the spatial plane can be obtained using the coordinates of three points and the normal vector: f i (x,y,z)=e i1 (x-x i1 ,)+e i2 (y-x i2 ,)+e i3 (z-x i3 ,)=0, By solving the equations of any two spatial planes simultaneously, we can obtain the equation of the line of intersection of the two spatial planes: Based on the position of the intersection of two spatial planes superimposed on the three-dimensional spatial model under the construction coordinate system, the coordinates of the closed area from the intersection of two spatial planes to the surface of the three-dimensional spatial model can be picked to form the spatial domain coordinate set Ω(x,y,z). All coordinate points in this spatial domain coordinate set are identified as the range of soil and rock that needs to be removed. This coordinate set is input into the vehicle information terminal as the discrimination standard. (3) A vehicle-mounted excavation positioning module is fixed on the mechanical bucket. The excavation work surface is located by using the relationship between the GPS satellite positioning system, the fixed signal base station on site and the vehicle-mounted excavation positioning module. This positioning data is sent in real time to the vehicle-mounted data processing terminal that accesses the warning coordinate set in step (2). The vehicle-mounted data processing terminal compares the received real-time excavation positioning coordinates with the warning coordinate set to form a warning feedback. When the construction area formed by the warning coordinate set is exceeded, an alarm is issued to correct the mechanical operation direction and work in the correct construction area.

2. The method for earthwork excavation in landslide control using three-dimensional oblique photography as described in claim 1, characterized in that: In step (1), the high-precision location of the original terrain of the construction area to be excavated, obtained by three-dimensional oblique photography, is used to form a three-dimensional spatial coordinate model. Specifically, three-dimensional oblique photography modeling technology is used to import high-definition images from different angles of the UAV into commercial processing software to quickly form a three-dimensional model and export an editable three-dimensional spatial coordinate model.

3. The method for earthwork excavation in landslide control using three-dimensional oblique photography as described in claim 1, characterized in that... The process of forming the three-dimensional spatial model under the precise construction coordinate system in step (1) is as follows: by collecting the coordinates of at least three fixed points in the construction coordinate system on site, calculating and marking the corresponding point coordinates of at least three fixed points in the three-dimensional spatial coordinate model of the three-dimensional oblique photography, and performing rotation and translation operations on the three-dimensional spatial coordinate model of the three-dimensional oblique photography so that the coordinates of at least three fixed points in the construction coordinate system are precisely matched with the coordinates in the three-dimensional spatial coordinate model, thus obtaining the three-dimensional spatial model under the construction coordinate system.

4. The method for earthwork excavation in landslide control using three-dimensional oblique photography according to claim 3, characterized in that, In step (1), the principle of calculating the coordinates of the fixed point in the three-dimensional spatial coordinate model of the three-dimensional oblique photography by collecting the coordinates of the fixed point in the construction coordinate system on site adopts the transformation of the spatial rectangular coordinate system. The specific process is as follows: Three coordinate points M1(m) are taken in the on-site construction coordinate system. 11 ,m 12 ,m 13 M2(m) 21 ,m 22 ,m 23 M3(m) 31 ,m 32 ,m 33 In the three-dimensional spatial coordinate model of three-dimensional oblique photography, three coordinate points N1(n) are taken. 11 ,n 12 ,n 13 ), N2(n 21 ,n 22 ,n 23 ), N3(n 31 ,n 32 ,n 33 And establish the following transformation relationship: The matrix T used for coordinate transformation can be calculated: T=M×N -1 Where T is the transformation matrix; N -1 M is the inverse matrix of N; M is the coordinate matrix of three points in the on-site construction coordinate system; N is the coordinate matrix of three points in the three-dimensional spatial coordinate model. Once the coordinate transformation matrix T is calculated, the coordinates L(l1, l2, l3) of any coordinate point K(k1, k2, k3) in the three-dimensional spatial model corresponding to any coordinate point K(k1, k2, k3) in the construction site coordinate system can be calculated using the following formula: Where K is a matrix composed of the coordinates of a point in the on-site construction coordinate system; L is a matrix composed of the coordinates of a point in the three-dimensional spatial coordinate model.

5. The method for earthwork excavation in landslide control using three-dimensional oblique photography as described in claim 1, characterized in that: The vehicle-mounted excavation positioning module is fixed on the mechanical bucket. The vehicle-mounted excavation positioning module maintains communication with the fixed signal base station and GPS navigation satellite at a certain frequency on site. It collects the coordinates of the mechanical bucket in real time and automatically inputs them into the vehicle-mounted data processing terminal. It determines whether the real-time coordinates of the mechanical bucket belong to the spatial domain coordinate set Ω and the distance from the boundary of the spatial domain coordinate set, and generates early warning and alarm. The next step is to correct the mechanical operation and implement the excavation action within the spatial domain coordinate set Ω, that is, the spatial range where the excavation operation needs to be carried out.

6. A method for earthwork excavation in landslide control using three-dimensional oblique photography as described in claim 5, characterized in that: The fixed signal base station at the site is located at a reference point with known coordinates and continuously receives all visible GPS satellite signals. The fixed signal base station transmits the station coordinates, pseudorange observations, carrier phase observations, satellite tracking status, and receiver operating status to the vehicle-mounted excavation positioning module via a wireless data link. The vehicle-mounted excavation positioning module first initializes and completes the search and solution of integer ambiguities before entering dynamic operation. While receiving data from the fixed signal base station at the site, the vehicle-mounted excavation positioning module simultaneously observes and collects GPS satellite carrier phase data. It solves the carrier phase integer ambiguity through differential processing within the system and obtains the rover's planar coordinates x, y, and elevation h based on the correlation between the vehicle-mounted excavation positioning module and the fixed signal base station at the site. These coordinates are the spatial coordinates of the construction coordinate system collected at the site.

7. A method for earthwork excavation in landslide control using three-dimensional oblique photography as described in claim 5, characterized in that: The mechanical bucket collects real-time coordinates A1(x1, x2, x3), and the on-board data processing terminal calculates the minimum distance L1 from point A1 to the boundary surface Ωs(x, y, z) of the spatial domain coordinate set according to the following formula: The warning operation is based on the relationship between the minimum distance L1 and the warning value L of the excavation boundary distance. Specifically: when 0 ≤ L1 ≤ L, a warning is issued to the operating end, and the mechanical operation reduces the corresponding movement amplitude; when 0 ≤ L1 ≤ L, a warning is issued ... When an alarm is triggered, it is sent to the control terminal, at which point the movement of the mechanical bucket in the forward direction is immediately stopped and corrected in time; the slack of the operation can be adjusted by changing the value of L.

8. A method for earthwork excavation in landslide control using three-dimensional oblique photography as described in claim 5, characterized in that: The mechanical bucket collects real-time coordinate points A1(x1, x2, x3). The onboard data processing terminal determines whether the warning value range has been reached and records these coordinate points according to frequency, forming a point set A. i (x1, x2, x3) are used to derive the coordinates of these point sets to form a spatial entity Ω. i The volume is calculated to represent the excavation work volume; the 3D model before excavation is used to determine the Ω... i Taking a Boolean subtraction operation yields the three-dimensional terrain model after excavation, which is the post-construction terrain coordinate set.

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