Material digging method based on image recognition

Abstract

The invention provides a material digging method based on image recognition, belongs to the technical field of image recognition application, and is realized based on a material pool, an excavator, an image acquisition device, a laser radar and a control unit. The excavator comprises an excavating arm and an opening and closing excavator bucket assembly. The method comprises the steps that a control unit combines two types of sensor data to construct a material pool global three-dimensional map, grids are divided, wave crest areas are screened, and an operation path is planned; after the excavator moves to a target point, selecting an excavating mode according to the distance between the wave crest and the excavator, using a first mode when the distance is smaller than the effective width of the bucket, and otherwise, using a second mode; and when no wave crest exists, a corresponding digging strategy also exists, the material pile data is updated in real time, and remote image monitoring is supported. According to the method, the complex environment sensing reliability and the digging efficiency are improved, equipment is protected, and multiple scenes are adapted.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of image recognition application, and in particular to a material digging method based on image recognition. BACKGROUND

[0002] A material pool is a device for storing raw materials, which is generally used for storing materials such as grains and sand, and since it is set below the ground level, the digging operation is mostly completed by a excavator. In the process of storing materials, the material pool generally relies on a truck for unloading, and during the unloading process, a material pile is formed in the material pool, and the material pile forms a wave crest. At present, the digging operation is mostly completed by manual operation of the excavator, but manual operation needs to rely on the experience of the operator for judgment, and since the material pool has a certain depth, the operation is complex. In order to improve the degree of automation, some schemes attempt to use sensors to sense the material pile and automatically dig the material. However, the existing digging mode of the excavator is relatively single, and it is difficult to adapt to different digging strategies according to the different distances between the wave crest of the material pile and the excavator, resulting in low efficiency of the excavator. SUMMARY

[0003] The purpose of the present application is to solve the above problems and provide a material digging method based on image recognition.

[0004] The technical scheme of the present application is as follows: The present application provides a material digging method based on image recognition, which is realized based on a material pool and a excavator movably deployed beside the material pool; The excavator comprises a digging arm and two mutually openable and closable buckets; an image acquisition device and a laser radar are installed on the edge of the material pool towards the inside of the material pool; a control unit is used to control the digging arm and the bucket to dig the material; The digging method comprises the following steps: S1, the control unit constructs a global three-dimensional map of the material pool based on the data of the image acquisition device and the laser radar; the material pool plane is divided according to a preset rule, the average height H(i,j) of each grid and the overall average height Havg of the material pile are calculated; the grids with H(i,j) > Havg are selected and clustered as continuous regions to obtain the wave crest region and the center coordinates thereof; a global operation path is planned for the excavator according to the positions of all the wave crests, wherein i represents the row number of the grid of the material pool plane, and j represents the column number of the grid; S2, the excavator is controlled to move to a target operation point along the global operation path, and the coordinate position of the current excavator is determined; S3, the straight line distance L1 between the wave crest and the side of the material pool close to the excavator is calculated, and it is judged whether the straight line distance L1 is greater than or equal to the effective digging width D of the bucket: if yes, the second digging mode is adopted; otherwise, the first digging mode is adopted; S4, after the digging is completed, return to step S3 to re-sense the state in the current working point range until there is no workable material at the current point, and then return to step S2; The first digging mode is to control the bucket to dig downward close to the inner wall of the side of the material pool close to the excavator, and the second digging mode is to adjust the angle of the bucket so that the bucket lip is all directed toward the slope of the material close to the excavator, and then control the two buckets to be inserted into the material for digging. In step S1, the global working path of the excavator is determined as follows: S101, compare the difference between the average height of each wave peak region and the overall average height of the material pile, and the wave peak region with a difference greater than a threshold value is preferentially included in the working range; if the height differences of multiple wave peak regions are similar, then further compare the areas of the wave peak regions, and the wave peak region with a larger area is preferentially worked; S102, according to the above priority rules, sort all wave peak regions from high to low to form the working target order of the excavator; S103, take the initial deployment position of the excavator as the starting point of the path, and sequentially set the center coordinates of each sorted wave peak region as path nodes; when planning the path, select the route with the shortest distance between adjacent nodes, and finally form the global working path.

[0005] Based on further improvements of the above structure, the excavator further comprises a pressure sensor for detecting the pressure acting on the bucket lip, and during the digging in the first digging mode, if the pressure exceeds a threshold value, it is judged that the bottom is touched, and after the bottom is touched, it returns to step S3.

[0006] Based on further improvements of the above structure, in step S1, the image acquisition device and the laser radar further acquire the slope angle of the material in the wave peak region; The excavator further comprises an angle sensor for detecting the digging angle of the bucket; The second digging mode further comprises adjusting the angle of the bucket according to the slope angle, and calibrating through the angle sensor so that the bucket lip is all directed toward the slope of the material close to the excavator, and then controlling the two buckets to be inserted into the material for digging.

[0007] Based on further improvements of the above structure, the image acquisition device comprises a binocular camera; The preset rule is to divide the material pool plane by a 1m×1m grid; The method for obtaining the peak region and its center coordinates includes: scanning the material pile in the material pool with a lidar to generate two-dimensional coordinates (x, y) of all points on the surface of the material pile relative to the excavator; preprocessing the point cloud to filter background points and noise points outside the material pool and retain effective points on the surface of the material pile; using statistical filtering to remove isolated points; and taking the center coordinates (x1, y1) of each region as the initial position of the peak based on the grid with H(i,j) > Havg obtained in step S1. The method for acquiring the position of the wave crest of the material in the pool using the image acquisition device and the lidar further includes: performing a secondary calibration on the initial position of the wave crest using the image acquisition device to obtain the final position of the wave crest. The image acquisition device targets the initial position (x1, y1) output by the lidar. The camera verifies the visual features and corrects the coordinates to output the final peak position, including: The camera and LiDAR are synchronized via a time sync device to ensure consistent data acquisition timing. Based on the camera's preset calibration parameters, the initial peak coordinates (x1, y1) of the LiDAR are mapped to the two-dimensional image pixel coordinates (u, v) of the camera, locating the corresponding peak candidate region in the image. A 50×50 pixel sub-region surrounding (u, v) in the image is extracted, and the visual characteristics of this region are analyzed. By using the parallax of the binocular cameras, the relative height gradient of the area is calculated to confirm whether the center position (u,v) is the highest point in the area; if the visual feature verification shows that (x1,y1) is the true highest point of the peak, the coordinates are directly retained. If the visual system detects a shift in the highest point within the region, the shifted two-dimensional coordinates (x2, y2) are deduced through coordinate mapping; the output (x2, y2) is then used as the final position of the peak. Using the excavator's coordinates as the origin (0,0), calculate the straight-line distance L1 based on the final position coordinates (x2,y2) of the wave crest; Methods for obtaining the slope angle of a wave crest from its final position include: Centered on the final position of the wave peak, a rectangular calculation area is formed by extending towards the excavator. The length of the rectangular calculation area is set along the slope extension direction, and the width is set perpendicular to the slope extension direction. From the 3D point cloud of the material pile acquired by the lidar, point clouds whose coordinates fall within the rectangular calculation area are selected to form a local point cloud subset. The local point cloud subset is denoised to remove isolated points and retain effective point clouds that can reflect the surface state of the material pile slope. The denoised effective point clouds are subjected to plane fitting to obtain a fitting plane that matches the surface morphology of the material pile slope. The angle between the fitting plane and the horizontal plane is calculated, and this angle is the slope angle of the corresponding slope area of ​​the material pile. During the excavation process, the image acquisition device transmits excavation images in real time for remote manual monitoring.

[0008] Based on further improvements to the above structure, the two buckets are respectively a first bucket and a second bucket, and the first bucket and the second bucket form a bucket assembly, wherein the back of the first bucket is arranged in a straight line structure, and the back of the second bucket is arranged in an arc shape structure.

[0009] Based on a further improvement to the above structure, the bucket assembly also includes: A first upper arm and a second upper arm, wherein the first upper arm is mounted on the first bucket and the second upper arm is mounted on the second bucket, and the first upper arm and the second upper arm are hinged to each other; The support frame has a hinge point where the first upper arm and the second upper arm are hinged to each other, which is rotatably connected to the inner side of the support frame via a rotating shaft. A first hydraulic cylinder and a second hydraulic cylinder, wherein the cylinder end of the first hydraulic cylinder is hinged to the inner top side of the support frame, and the telescopic end is hinged to the upper end of the first upper arm; the cylinder end of the second hydraulic cylinder is hinged to the inner top side of the support frame, and the telescopic end is hinged to the upper end of the second upper arm; and two pressure sensors are provided, which are respectively installed at the pressure measuring ports of the first hydraulic cylinder and the second hydraulic cylinder. A connecting frame, the front end of which is rotatably connected to the support frame, and the rear end of which is rotatably connected to the excavator's boom; The third hydraulic cylinder has its cylinder end hinged to the inner side of the top of the connecting frame, and its telescopic end hinged to the outer side of the support frame. The control unit is connected to and controls the excavator arm, the first hydraulic cylinder, the second hydraulic cylinder, and the third hydraulic cylinder. The control unit drives the opening and closing of the first bucket and the second bucket by controlling the extension and retraction of the first hydraulic cylinder and / or the second hydraulic cylinder. The control unit adjusts the orientation of the first bucket and the second bucket by controlling the extension and retraction of the third hydraulic cylinder.

[0010] Based on further improvements to the above structure, the first mining mode includes the following steps: S11. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to open the first bucket and the second bucket to the maximum angle, adjusts the action of the digging arm so that the back of the first bucket is in close contact with the inner wall of the material pool, and drives the entire bucket assembly to move vertically downward so that the first bucket and the second bucket are inserted into the material pile. S12. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to close the first bucket and the second bucket together, and then controls the excavator's arm to pull out the bucket assembly to complete the digging. In step S11, when the bucket assembly moves downward, if it is determined that the bucket has touched the bottom, the downward movement of the bucket is stopped. Then, in step S12, during the process of the first bucket and the second bucket closing with each other, the bucket lips of the first bucket and the second bucket are ensured to be in contact with the inner bottom surface of the material pool.

[0011] Based on further improvements to the above structure, the second mining mode includes the following steps: S21. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to open the first bucket and the second bucket to the maximum angle, and adjusts the angle of the bucket assembly by the third hydraulic cylinder so that the bucket lips of the first bucket and the second bucket face the slope closer to the excavator. The control unit controls the arm so that the bucket lips of the first bucket and the second bucket are inserted into the slope facing the slope closer to the excavator. S22. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to close the first bucket and the second bucket together, and then controls the excavator's arm to pull out the bucket assembly to complete the digging.

[0012] Based on further improvements to the above structure, the lidar defines the wave peak as an area with a relative height ≥ 0.5m or a slope angle > 30°. The relative height is the difference between the overall average height Havg of the stockpile and the height of the target stockpile. The excavation method further includes: if no wave peak is detected, the control unit controls the excavator to excavate in place; for areas beyond the effective excavation width D of the bucket, the following steps are used for excavation: S311. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to open the first bucket and the second bucket to the maximum angle. The angle of the bucket assembly is adjusted by the extension and retraction of the third hydraulic cylinder so that the bucket lips of the first bucket and the second bucket face the surface of the material pile. The control unit controls the digging arm so that the bucket lips of the first bucket and the second bucket are inserted into the material pile at a vertical angle. S312. The control unit controls the first bucket and the second bucket to close together, and then controls the excavator's arm to pull out the bucket assembly to complete the digging. For areas within the effective digging width D of the bucket, the first digging mode is used for digging.

[0013] The advantages or beneficial effects of the above technical solution include at least the following: The material excavation method based on image recognition of this invention, through the collaborative work of lidar and image acquisition device, secondary calibration, and redundant sensing design, effectively avoids data deviation of a single sensor in complex environments such as strong light and high dust, reduces system misjudgment, ensures the accuracy of material pile crest positioning and slope angle calculation, and ensures stable operation; at the same time, by constructing a global three-dimensional map of the material pool, dividing the crest area into grids and planning the global operation path, and selecting an appropriate excavation mode based on the distance between the crest and the excavator, the extension distance of the excavator arm is shortened as much as possible, reducing the time consumed in a single excavation. It improves overall operational efficiency; it also utilizes pressure sensors to determine bottoming in the first digging mode, preventing the bucket from excessively descending and damaging the equipment. Furthermore, the bucket assembly improves the opening and closing angle and torque through structural optimization of the hydraulic cylinder and upper arm. It is designed with corresponding digging modes for scenarios with or without peaks and different peak distances, adapting to diverse digging needs and reducing equipment wear. In addition, it adjusts the peak position by updating the 3D point cloud data of the material pile in real time, ensuring that the operation is carried out based on real-time working conditions to improve digging accuracy. The image acquisition device can also transmit digging images in real time to support remote manual monitoring, facilitating timely handling of abnormal situations and further ensuring operational stability. Attached Figure Description

[0014] The accompanying drawings illustrate exemplary embodiments of the present application and, together with the description thereof, serve to explain the principles of the present application. These drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification.

[0015] Figure 1 A schematic diagram showing the positional relationship between the excavator and the material pool according to an embodiment of the present invention is shown; Figure 2 A schematic diagram of the structure of the bucket assembly according to an embodiment of the present invention is shown; Figure 3 A schematic diagram showing the change in bucket orientation after the third hydraulic cylinder extends and retracts according to an embodiment of the present invention is shown; Figure 4 A schematic diagram of the assembly of the bucket assembly according to an embodiment of the present invention is shown; Figure 5 An assembly diagram of the first and second buckets according to an embodiment of the present invention is shown; Figure 6 The figure shows a schematic diagram of the steps of the first digging mode of the present invention. In the figure, step a is to press the back of the first bucket against the side wall of the material pool, step b is to scoop the first bucket and the second bucket into the material and the bucket lip touches the bottom, and steps c and d are to close the first bucket and the second bucket to complete the material digging. Figure 7The diagram illustrates a second digging mode according to an embodiment of the present invention, in which the bucket is oriented toward a slope, and the dashed arrows in the diagram indicate the digging direction of the bucket. Figure 8 A schematic diagram showing that the wave crest appears outside the excavation width D according to an embodiment of the present invention is illustrated; Figure 9 This diagram illustrates a scenario where the wave crest appears within the excavation width D according to an embodiment of the present invention. Figure 10 The diagram shows a rotating platform of an excavator according to an embodiment of the present invention rotating toward a target area and then rotating a connecting frame such that the first bucket is in close contact with the side wall of the hopper. Figure 11 The diagram shows a comparison of the opening angle of the bucket assembly of this application and the bucket assembly of the prior art, with the upper part of the figure showing the bucket assembly of this application and the lower part showing the bucket assembly of the prior art. Figure 12 The diagram shows a comparison of the digging directions of the first digging mode and the second digging mode under an embodiment of the present invention. The upper part of the diagram represents the first digging mode, and the lower part represents the second digging mode. The blue arrows indicate the digging direction of the bucket, and the red arrows indicate the dumping direction of the material pile after digging. Figure 13 The diagram shows the deployment location of the distance sensor according to an embodiment of the present invention; the red dashed line in the diagram is the detection line of the distance sensor, X and Y represent the X-axis and Y-axis of the coordinate system, and O represents the origin of the coordinate system.

[0016] Reference numerals: 10, material pool; 20, excavator; 21, excavator arm; 22, bucket assembly; 221, first bucket; 222, second bucket; 223, support frame; 224, connecting frame; 225, first hydraulic cylinder; 226, second hydraulic cylinder; 227, third hydraulic cylinder; 2201, first upper arm; 2202, second upper arm; 23, base; 30, distance sensor. Detailed Implementation

[0017] Embodiments of the present invention provide a material extraction method based on image recognition, such as... Figure 1 As shown, the method is implemented based on a material pool and an excavator that can be mobilely deployed next to the material pool; The excavator includes: a digging arm and two buckets that can open and close to each other; an image acquisition device and a lidar are installed on the edge of the hopper facing into the hopper; and a control unit for controlling the digging arm and buckets to dig up materials. The mining method includes the following steps: S1. The control unit constructs a global 3D map of the material pool based on data from the image acquisition device and LiDAR. It divides the material pool plane according to preset rules, specifically into 1m×1m grids, and calculates the average height H(i,j) of each grid and the overall average height Havg of the material pile. Grids where H(i,j) > Havg are selected and clustered into continuous regions, yielding peak regions and their center coordinates. Based on the positions of all peaks, a global operation path is planned for the excavator, where i represents the row number of the material pool plane grid, and j represents the column number. Specifically, i corresponds to the grid number in the y-axis direction (row), j corresponds to the grid number in the x-axis direction (column), and H(i,j) is the average height of all effective point clouds within the grid "row i, column j," used for subsequent comparison with the overall average height of the material pile to select peak regions.

[0018] S2. Control the excavator to move along the global operation path to a target operation point and determine the current coordinate position of the excavator; S3. Calculate the straight-line distance L1 between the wave crest and the side of the material pool near the excavator, and determine whether the straight-line distance L1 is greater than or equal to the effective digging width D of the bucket. If yes, the second digging mode is adopted. The second digging mode is: adjust the angle of the bucket so that the bucket lips are both facing the slope of the material near the excavator, and then control the two buckets to insert into the material for digging. Otherwise, the first digging mode is adopted. The first digging mode is: control the bucket to dig downwards close to the inner wall of the material pool near the excavator.

[0019] S4. After the excavation is completed, return to step S3, re-sensor the status within the current work point area until there is no workable material at the current point, and then return to step S2.

[0020] In step S1, the global operation path of the excavator is determined according to the following steps: S101. Compare the difference between the average height of each peak region and the average height of the entire stockpile. Peak regions with a difference greater than a threshold are prioritized for operation. If the height differences of multiple peak regions are similar, the area of ​​the peak regions is further compared, and the peak region with the larger area is prioritized for operation. First, based on the average height H(k) of each peak region obtained in step S1, where k is the peak number, for example: k=1,2,...,n, it is also necessary to obtain the average height Havg of the entire stockpile and calculate the height difference of each peak region: ΔH(k)=H(k)-Havg where ΔH(k) represents the difference between the average height of the kth peak region and the average height of the entire stockpile. The larger the positive value, the more prominent the material accumulation in the peak region.

[0021] Set a height difference threshold ΔH0 (which can be preset according to material characteristics, for example, ΔH0=0.3m), and prioritize including the peak area where ΔH(k)>ΔH0 into the work area (these peaks are "high priority peaks" and should be handled first to avoid material accumulation leading to collapse or excavation difficulties).

[0022] If the height difference between multiple peak regions satisfies |ΔH(k1)-ΔH(k2)|≤0.1m (i.e., the height differences are similar; 0.1m is the threshold for similarity and can be adjusted according to the actual scenario), then the area S(k) of each peak region is further compared (S(k) is the total number of grids contained in the continuous region obtained by clustering in step S1 multiplied by the area of ​​a single grid; for example, in the case of a 1m×1m grid, S(k) = number of grids × 1m). 2 Larger wave crest areas (i.e., those containing more material) should be prioritized for operation.

[0023] S102. According to the above priority rules, sort all peak regions from high to low to form the excavator's work target sequence: Step 1: Sort all peaks in descending order of ΔH(k), with peaks having larger ΔH(k) appearing earlier in the order; Step 2: For wave peaks with similar ΔH(k) (satisfying |ΔH(k1)-ΔH(k2)|≤0.1m), sort them in descending order of their area S(k), with the wave peaks with larger areas being sorted earlier; The final task target sequence list is formed as follows: [k1,k2,...,kn], where k1 is the first task peak and kn is the last task peak.

[0024] For example: If there are 3 wave peaks with ΔH values ​​of 0.8m, 0.75m, and 0.4m respectively, and their areas are 5m², then... 2 8m 2 10m 2 Since the difference between 0.8m and 0.75m is 0.05m (≤0.1m), they are considered to have similar heights. Therefore, the area to be compared is 8m². 2 >5m 2 Therefore, the sorting order is [k2,k1,k3].

[0025] S103. Taking the excavator's initial deployment position as the path starting point, the center coordinates of each sorted peak area are set as path nodes; when planning the path, the route with the shortest distance between adjacent nodes is selected, ultimately forming the global operation path: The initial deployment position of the excavator is taken as the starting point of the path, and is denoted as coordinate P0(x0,y0) (this coordinate can be obtained through the excavator's own positioning device, such as the relative positioning of GPS or LiDAR and the fixing device on the edge of the material pool).

[0026] The center coordinates of the sorted peak regions in step S22 are used as path nodes in sequence, namely P1(x1,y1), P2(x2,y2), ..., Pn(xn,yn), where (xk,yk) is the center coordinate of the kth peak, which is determined by the method of obtaining "peak regions and their center coordinates" in step S1.

[0027] When planning paths between adjacent nodes, the optimization objective is "shortest distance," meaning that the path between adjacent nodes Pi(xi,yi) and Pj(xj,yj) is chosen based on the shortest straight-line distance. The distance calculation formula is as follows: ; The global job path is a continuous route starting from the starting point P0 and passing through P1→P2→...→Pn in sequence. That is, the path sequence is: P0→P1→P2→...→Pn.

[0028] This path planning method ensures that the excavator completes operations in all peak areas with the shortest travel distance, reducing ineffective travel time and improving digging efficiency. At the same time, by prioritizing the handling of peaks with prominent heights and large material volumes, it avoids increased digging difficulty or safety hazards caused by excessive local accumulation of material.

[0029] There are several ways to determine the current coordinates of the excavator: The first method is to use the BeiDou or GPS positioning system to determine whether the excavator has reached the coordinates of the target work point. The second method is: such as Figure 13 As shown, distance sensors are installed at both ends of each side of the opening at the top of the material pool to detect the distance between the excavator and each distance sensor. The distance is correlated with coordinates, where the coordinates are a coordinate system with a corner of the material pool as the origin. Figure 13 As shown in the figure, the thick black line represents the coordinate system. The two red dashed lines at the top and bottom are parallel to the X-axis of the coordinate system, and the two red dashed lines on the left and right are parallel to the Y-axis of the coordinate system. Therefore, the coordinates of the excavator in the coordinate system can be obtained by reading the degree of the distance sensor.

[0030] Based on the further improvements to the above structure, the excavator also includes a pressure sensor to detect the pressure acting on the bucket lip. During the digging process in the first digging mode, if the pressure exceeds the threshold, it is determined that the bottom has been reached, and after the bottom has been reached, the process returns to step S3.

[0031] It should be noted that the effective digging width D of the bucket is the digging width after the two buckets are opened to their maximum angle and then dig and close with one scoop, not the maximum working range of the excavator arm 21 after it is extended.

[0032] The first mining mode is as follows: Figure 12As shown in the upper part, the bucket is controlled to dig downwards close to the inner wall of the material pool 10 near the excavator 20. During this process, the pressure sensor determines whether it has reached the bottom. After reaching the bottom, the process returns to step S1. In the figure, the blue arrow indicates the digging direction, and the red arrow indicates the direction in which the material at the crest of the wave collapses after digging because it loses the support of the material in the blue arrow area. The second mining mode is: such as Figure 12 As shown in the lower part, the angle of the buckets is adjusted so that the bucket lips face the slope on the side of the material closer to the excavator 20, and then the two buckets are controlled to insert into the material to dig. In the figure, the blue arrows indicate the digging direction, and the red arrows indicate the direction in which the material at the crest of the wave collapses after digging because it loses the support of the material in the blue arrow area.

[0033] Whether it is the first digging mode or the second digging mode, the goal is to dig the part of the material that is as close to the excavator 20 as possible, so as to minimize the extension distance of the excavator arm 21 and shorten the digging time of a single digging.

[0034] The image acquisition device includes a binocular camera; The process involves using a lidar to collect three-dimensional point cloud data of the material pile within the material pool 10 to determine the initial position of the material's peak. Then, an image acquisition device is used to perform a secondary calibration of the initial position of the peak. In environments with strong light (such as direct sunlight on the material pile at noon, causing reflection interference) or high dust (dust during sand and gravel excavation), the point cloud quality of the lidar may decrease (fewer effective points, more noise). In such cases, the image acquisition device can serve as an auxiliary sensing method to reduce the system's misjudgment rate. The method for obtaining the final position of the wave crest described above includes: wherein the image acquisition device and the lidar acquire the position of the wave crest of the material in the pool by means of: The lidar scans the material pile within the material pool, generating two-dimensional coordinates (x, y) of all points on the pile surface relative to the excavator. Point cloud preprocessing filters out background and noise points outside the material pool, retaining valid points on the pile surface. Statistical filtering removes isolated points. The material pool plane is divided into 1m×1m grids, and valid points are assigned to their corresponding grids. The average height H(i, j) of each grid and the overall average height Havg of the material pile are calculated. Grids with H(i, j) > Havg are selected from the initial peak regions, clustered into continuous regions, and the center coordinates (x1, y1) of each region are taken as the initial peak position. The method for acquiring the position of the wave crest of the material in the pool using the image acquisition device and the lidar further includes: performing a secondary calibration on the initial position of the wave crest using the image acquisition device to obtain the final position of the wave crest. The image acquisition device targets the initial position (x1, y1) output by the lidar. The camera verifies the visual features and corrects the coordinates to output the final peak position, including: The camera and LiDAR are synchronized via a time sync device to ensure consistent data acquisition timing. Based on the camera's preset calibration parameters, the initial peak coordinates (x1, y1) of the LiDAR are mapped to the two-dimensional image pixel coordinates (u, v) of the camera, locating the corresponding peak candidate region in the image. A 50×50 pixel sub-region surrounding (u, v) in the image is extracted, and the visual characteristics of this region are analyzed. By using the parallax of the binocular cameras, the relative height gradient of the area is calculated to confirm whether the center position (u,v) is the highest point in the area; if the visual feature verification shows that (x1,y1) is the true highest point of the peak, the coordinates are directly retained. If the visual system detects a shift in the highest point within the region, the shifted two-dimensional coordinates (x2, y2) are deduced through coordinate mapping; the output (x2, y2) is then used as the final position of the peak. Using the excavator's coordinates as the origin (0,0), calculate the straight-line distance L1 based on the final position coordinates (x2,y2) of the wave crest; Methods for obtaining the slope angle of a wave crest from its final position include: Centered on the final position of the wave peak, a rectangular calculation area is formed by extending towards the excavator. The length of the rectangular calculation area is set along the slope extension direction, and the width is set perpendicular to the slope extension direction. From the 3D point cloud of the material pile acquired by the lidar, point clouds whose coordinates fall within the rectangular calculation area are selected to form a local point cloud subset. The local point cloud subset is denoised to remove isolated points and retain effective point clouds that can reflect the surface state of the material pile slope. The denoised effective point clouds are subjected to plane fitting to obtain a fitting plane that matches the surface morphology of the material pile slope. The angle between the fitting plane and the horizontal plane is calculated, and this angle is the slope angle of the corresponding slope area of ​​the material pile. The method for obtaining the slope angle of a wave crest through its final position further includes: adding at least two adjacent rectangular verification areas around the final position of the wave crest, repeating the above steps, and calculating the slope angle corresponding to each verification area respectively; performing a weighted average processing on the slope angle and the slope angle corresponding to each verification area, with the weighting weights distributed according to the distance between the area and the final position of the wave crest, the closer the distance, the higher the weight, to obtain the final material pile slope angle; Specifically, let the main calculation area centered on the final position of the wave crest be A0, and the slope angle calculated therein be θ0; the two additional adjacent verification areas are A1 and A2, and the corresponding slope angles calculated are θ1 and θ2. If more verification areas are added later, they can be expanded according to this logic, such as A3, θ3, etc. I. Setting distance parameters: Let d0, d1, and d2 be the straight-line distances from the center point of each region to the final position of the wave crest. Key rule: The center point of the main region A0 is the final position of the wave crest, so d0 = 0 (closest distance). A1 and A2 are adjacent regions, and the distance satisfies d1 < d2 (or can be adjusted according to the actual layout, just ensure that "the closer to the wave crest, the smaller the d value").

[0035] II. Mathematical Model Calculation Step 1: Calculate the weights of each region (W0, W1, W2); The core logic of weighting is: the smaller the distance d, the larger the weight W, and the sum of the weights of all regions is 1.

[0036] The basic weights are calculated using the "reciprocal of distance," and then "normalization" is applied to ensure that the sum of the weights is 1, as detailed below: 1. First, calculate the basic weights: Main region A0: Since d0=0, its basic weight is directly set to a fixed value (such as K, it is recommended to take 2 to ensure that its weight is maximized). Validation region A1: Basic weight = 1 / d1; Validation region A2: Basic weight = 1 / d2; 1. Then perform weight normalization (ensuring W0 + W1 + W2 = 1): Total base weight = K + (1 / d1) + (1 / d2); Main region weight: W0 = K / [K + (1 / d1) + (1 / d2)]; Validation region A1 weight: W1=(1 / d1) / [K+(1 / d1)+(1 / d2)]; Weight of verification region A2: W2=(1 / d2) / [K+(1 / d1)+(1 / d2)]; Step 2: Calculate the final slope angle (θ_final) The final result is obtained by weighted summation of "weight × slope angle": θ_final=W0×θ0+W1×θ1+W2×θ2; Example illustration: Assume a real-world scenario where: Main region A0: θ0=35°, d0=0, take K=2; Verification area A1: distance d1=1m, θ1=33°; Verification area A2: distance d2=2m, θ2=31°; Step 1: Calculate the weights: 1. Basic weights: A0 base weight = 2; A1 base weight = 1 / 1 = 1; A2 base weight = 1 / 2 = 0.5; Total base weight = 2 + 1 + 0.5 = 3.5; 1. Normalized weights: W0 = 2 / 3.5 ≈ 0.57 (57%); W1 = 1 / 3.5 ≈ 0.29 (29%); W2 = 0.5 / 3.5 ≈ 0.14 (14%); This conforms to the principle that "the closer the distance, the higher the weight": A0 > A1 > A2; Step 2: Calculate the final slope angle: θ_final=0.57×35°+0.29×33°+0.14×31°≈33.8°.

[0037] It is important to note that the quality of point cloud acquisition by lidar is easily degraded in environments with strong light (such as direct sunlight on a material pile at noon, where reflected signals interfere with point cloud quality) and high dust (such as dust generated during sand and gravel excavation obscuring the laser), which may lead to failure in peak location and slope angle calculation. Image acquisition devices can serve as redundant sensing means. When lidar data is abnormal, visual images (which can still identify the general outline of the material pile even in strong light / dust environments) can be used to help confirm the approximate location of the peak and determine the slope direction, avoiding system downtime due to the failure of a single sensor and improving the adaptability of the solution in complex operating environments.

[0038] During the excavation process, the image acquisition device can also transmit excavation images in real time for remote manual monitoring.

[0039] The first digging mode described above involves controlling one of the buckets to dig downwards close to the inner wall of the material pool 10 near the excavator 20. During the digging process in the first digging mode, the value of the pressure sensor is detected in real time. When the preset value is reached, it is determined that the bucket lip has touched the bottom and the bucket stops moving downwards. The second digging mode is to adjust the angle of the buckets according to the slope angle, and calibrate it through the angle sensor so that the bucket lips are facing the slope of the material closer to the excavator 20, and then control the two buckets to insert into the material for digging. When lidar calculates the slope angle by fitting a local point cloud plane, if there are local collapses (such as depressions formed by loose grain accumulation) or protrusions (such as local agglomerations of sand and gravel) on the surface of the material pile, the fitted plane may deviate from the actual slope shape. The camera can extract the visual contour line corresponding to the slope calculation area and use the angle between the contour line and the horizontal line to help verify the slope angle calculated by lidar. If the deviation between the two exceeds the threshold, it can trigger lidar to refit the point cloud to ensure that the final slope angle is consistent with the actual slope shape of the material pile. This provides a reliable basis for "adjusting the bucket angle according to the slope angle" in the second digging mode and avoids insufficient bucket insertion depth or excessive disturbance of the material pile due to slope angle deviation.

[0040] After each excavation is completed, the three-dimensional point cloud data of the material pile is re-acquired by lidar to update the position of the peak, instead of excavating based on the data collected the first time, until the material removal operation is completed.

[0041] like Figure 2 As shown, the two buckets mentioned above are the first bucket 221 and the second bucket 222, which together form the bucket assembly 22. The back of the first bucket 221 is arranged in a straight line, while the back of the second bucket 222 is arranged in an arc shape. Bucket assembly 22 also includes: The first upper arm 2201 and the second upper arm 2202 are hinged to each other. The hinge point where the first upper arm 2201 and the second upper arm 2202 are hinged to each other is rotatably connected to the inner side of the support frame 223 through a rotating shaft; like Figure 4 , Figure 5 and Figure 7 As shown, there is a first hydraulic cylinder 225 and a second hydraulic cylinder 226. The cylinder end of the first hydraulic cylinder 225 is hinged to the inner top side of the support frame 223, and the telescopic end is hinged to the upper end of the first upper arm 2201. The cylinder end of the second hydraulic cylinder 226 is hinged to the inner top side of the support frame 223, and the telescopic end is hinged to the upper end of the second upper arm 2202. There are two pressure sensors, which are respectively installed at the pressure measuring ports of the first hydraulic cylinder 225 and the second hydraulic cylinder 226. The pressure from the bucket lip will be transmitted to the first hydraulic cylinder 225 and the second hydraulic cylinder 226. The pressure measuring port indicates whether the bucket lip has touched the bottom.

[0042] like Figure 2 As shown, a first hydraulic cylinder 225 is mounted above the second bucket 222, driving the first bucket 221 to rotate. A second hydraulic cylinder 226 is mounted above the first bucket 221, driving the second bucket 222 to rotate. The two hydraulic cylinders can be controlled independently. This design also increases the torque required to rotate the first and second buckets 221 and 222 via the first and second upper arms 2201 and 2202. Compared to existing technology that directly hinges the telescopic ends of the hydraulic cylinders to the bucket back, this design not only achieves greater torque under the same hydraulic cylinder thrust but also increases the bucket's opening and closing angle. Figure 11 As shown.

[0043] The connecting frame 224 is rotatably connected to the support frame 223 at its front end. An angle sensor is installed at the pivot of the connecting frame 224 and the support frame 223 to identify the bucket's entry angle. The rear end is rotatably connected to the excavator arm 21 of the excavator 20. Specifically, a motor is installed at the bottom of the connecting frame 224, and a pivot is fixed at the front end of the excavator arm 21. The pivot rotatably passes through the upper end of the connecting frame 224 and is equipped with a first gear. A second gear that meshes with the first gear is installed at the output end of the motor, thereby rotating the connecting frame 224 (the motor, the first gear, and the second gear are not shown in the figure). In the first digging mode, one of the buckets needs to be pressed against the side wall of the material pool 10. Therefore, the rotating platform of the excavator 20 needs to rotate towards the target area on both sides, and then the output end of the drive motor rotates, driving the second gear through the first gear to rotate, thereby realizing the rotation of the connecting frame 224. This allows the bucket back of one of the buckets to be pressed against the side wall of the material pool 10. Figure 10 As shown.

[0044] The third hydraulic cylinder 227 has its cylinder end hinged to the inner side of the top of the connecting frame 224, and its telescopic end hinged to the outer side of the support frame 223. The control unit is connected to and controls the excavator arm 21, the first hydraulic cylinder 225, the second hydraulic cylinder 226 and the third hydraulic cylinder 227. The control unit drives the opening and closing of the first bucket 221 and the second bucket 222 by controlling the extension and retraction of the first hydraulic cylinder 225 and / or the second hydraulic cylinder 226. The control unit adjusts the orientation of the first bucket 221 and the second bucket 222 by controlling the extension and retraction of the third hydraulic cylinder 227.

[0045] The first mining mode described above includes the following steps: S11, the control unit controls the first hydraulic cylinder 225 and / or the second hydraulic cylinder 226 to open the first bucket 221 and the second bucket 222 to their maximum angle, adjusts the movement of the digging arm 21 so that the back of the first bucket 221 is pressed tightly against the inner wall of the material pool 10, and drives the entire bucket assembly 22 to move vertically downward, so that the first bucket 221 and the second bucket 222 are inserted into the material pile, such as... Figure 6 Steps a to b are shown below; S12, the control unit controls the first hydraulic cylinder 225 and / or the second hydraulic cylinder 226 to close the first bucket 221 and the second bucket 222 together. After controlling the excavator arm 21 to pull out the bucket assembly 22, the digging is completed. Figure 6 Steps c through d are shown; In step S11, when the bucket assembly 22 moves downward, if it is determined that the bucket has touched the bottom, the bucket stops moving downward. Then, in step S12, during the process of the first bucket 221 and the second bucket 222 closing with each other, the bucket lips of the first bucket 221 and the second bucket 222 are ensured to be in contact with the inner bottom surface of the material pool 10.

[0046] The second mining mode includes the following steps: S21. The control unit controls the first hydraulic cylinder 225 and / or the second hydraulic cylinder 226 to open the first bucket 221 and the second bucket 222 to the maximum angle. The third hydraulic cylinder 227 adjusts the angle of the bucket assembly 22 so that the bucket lips of the first bucket 221 and the second bucket 222 face the slope closer to the excavator 20. The control unit controls the arm 21 so that the bucket lips of the first bucket 221 and the second bucket 222 are inserted into the slope facing the slope closer to the excavator 20. S22, the control unit controls the first hydraulic cylinder 225 and / or the second hydraulic cylinder 226 to close the first bucket 221 and the second bucket 222 together, and then controls the excavator arm 21 to pull out the bucket assembly 22 to complete the digging.

[0047] like Figure 8 As shown, if the calculated position of the wave crest is at point A, and it is determined that point A1 is the slope of the wave crest near the excavator 20, and the distance from point A to the side of the hopper 10 near the excavator 20 is the actual straight-line distance L1, it is clearly within the effective digging width D of the bucket. The control unit controls the excavator 20 to dig at the position of point A1 in the second digging mode; Figure 9 As shown, if the calculated position of the wave crest is located at point B, and the distance from point B to the side of the material pool 10 near the excavator 20 is the actual straight-line distance L1, it is clear that it has not invaded the effective digging width D of the bucket, and point B is near the side of the material pool 10 near the excavator 20. The control unit controls the excavator 20 to dig at the position of point B in the first digging mode.

[0048] If the wave crest is outside the maximum working range of excavator 20, move excavator 20 until the wave crest is within the maximum working range.

[0049] Furthermore, the lidar defines the peak as the area with a relative height ≥ 0.5m or a slope angle > 30°. The relative height is the difference between the overall average height of the stockpile, Havg, and the height of the target stockpile. The excavation method further includes: if no wave peak is detected, the control unit controls the excavator to excavate in place; for areas beyond the effective excavation width D of the bucket, the following steps are used for excavation: S311, The control unit controls the first hydraulic cylinder 225 and / or the second hydraulic cylinder 226 to open the first bucket 221 and the second bucket 222 to the maximum angle, and adjusts the angle of the bucket assembly 22 by extending and retracting the third hydraulic cylinder 227 so that the bucket lips of the first bucket 221 and the second bucket 222 face the surface of the material pile. The control unit controls the digging arm 21 so that the bucket lips of the first bucket 221 and the second bucket 222 are inserted into the material pile at a vertical angle. S312, The control unit controls the first bucket 221 and the second bucket 222 to close together, and after controlling the excavator arm 21 of the excavator 20 to pull out the bucket assembly 22, the digging is completed; For areas within the effective digging width D of the bucket, the first digging mode is used for digging.

[0050] In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0051] Those skilled in the art should understand that the above embodiments are merely for illustrative purposes and are not intended to limit the scope of this application. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of this application.

Claims

1. A material extraction method based on image recognition, characterized in that: The method is based on a material pool and an excavator that can be mobilely deployed next to the material pool; The excavator includes: a digging arm and two buckets that can open and close to each other; an image acquisition device and a lidar facing into the material pool are installed on the edge of the material pool; and a control unit is used to control the digging arm and buckets to dig up the material. The mining method includes the following steps: S1. The control unit constructs a global 3D map of the material pool based on data from the image acquisition device and LiDAR; it divides the material pool plane according to preset rules, calculates the average height H(i,j) of each grid and the overall average height Havg of the material pile; it filters out grids where H(i,j) > Havg, clusters them into continuous regions, and obtains the peak regions and their center coordinates; based on the position of all peaks, it plans a global operation path for the excavator, where i represents the row number of the material pool plane grid and j represents the column number of the grid. S2. Control the excavator to move along the global operation path to a target operation point, and determine the current coordinate position of the excavator; S3. Calculate the straight-line distance L1 between the wave crest and the material pool near the excavator side, and determine whether the straight-line distance L1 is greater than or equal to the effective digging width D of the bucket: if yes, then adopt the second digging mode; otherwise, adopt the first digging mode. S4. After the excavation is completed, return to step S3, re-sensor the status within the current work point area until there is no workable material at the current point, and then return to step S2. The first digging mode is: controlling the bucket to dig downwards close to the inner wall of the material pool near the excavator. The second digging mode is: adjusting the angle of the bucket so that the bucket lips face the slope of the material near the excavator, and then controlling the two buckets to insert into the material for digging. In step S1, the global operation path of the excavator is determined according to the following steps: S101. Compare the difference between the average height of each wave crest region and the average height of the entire stockpile. Wave crest regions with a difference greater than the threshold are given priority to be included in the work scope. If the height differences of multiple wave crest regions are similar, then the area of ​​the wave crest regions is further compared. Wave crest regions with larger areas are given priority to be worked on. S102. According to the above priority rules, sort all peak areas from high to low to form the excavator's work target sequence; S103. Taking the initial deployment position of the excavator as the starting point of the path, the center coordinates of each sorted peak area are set as path nodes in sequence; when planning the path, the route with the shortest distance between adjacent nodes is selected, and finally a global operation path is formed.

2. The material extraction method based on image recognition according to claim 1, characterized in that: The excavator also includes a pressure sensor for detecting the pressure acting on the bucket lip. During the excavation process in the first digging mode, if the pressure exceeds the threshold, it is determined that the bottom has been reached, and after the bottom has been reached, the process returns to step S3.

3. The material extraction method based on image recognition according to claim 1, characterized in that: In step S1, the image acquisition device and the lidar further acquire the slope angle of the material in the area where the wave crest is located; The excavator further includes an angle sensor for detecting the angle of entry of the bucket. The second digging mode further includes adjusting the angle of the buckets according to the slope angle, calibrating the angle sensor so that the bucket lips are all facing the slope of the material closer to the excavator, and then controlling the two buckets to insert into the material for digging.

4. The material extraction method based on image recognition according to claim 1, characterized in that: The image acquisition device includes a binocular camera; The preset rule is to divide the material pool plane into a 1m×1m grid; The method for obtaining the peak region and its center coordinates includes: scanning the material pile in the material pool with a lidar to generate two-dimensional coordinates (x, y) of all points on the surface of the material pile relative to the excavator; preprocessing the point cloud to filter background points and noise points outside the material pool and retain effective points on the surface of the material pile; using statistical filtering to remove isolated points; and taking the center coordinates (x1, y1) of each region as the initial position of the peak based on the grid with H(i,j) > Havg obtained in step S1. The method for acquiring the position of the wave crest of the material in the pool using the image acquisition device and the lidar further includes: performing a secondary calibration on the initial position of the wave crest using the image acquisition device to obtain the final position of the wave crest. The image acquisition device targets the initial position (x1, y1) output by the lidar. The camera verifies the visual features and corrects the coordinates to output the final peak position, including: The camera and LiDAR are synchronized via a time sync device to ensure consistent data acquisition timing. Based on the camera's preset calibration parameters, the initial peak coordinates (x1, y1) of the LiDAR are mapped to the two-dimensional image pixel coordinates (u, v) of the camera, locating the corresponding peak candidate region in the image. A 50×50 pixel sub-region surrounding (u, v) in the image is extracted, and the visual characteristics of this region are analyzed. By using the parallax of the binocular cameras, the relative height gradient of the area is calculated to confirm whether the center position (u,v) is the highest point in the area; if the visual feature verification shows that (x1,y1) is the true highest point of the peak, the coordinates are directly retained. If the visual system detects a shift in the highest point within the region, the shifted two-dimensional coordinates (x2, y2) are deduced through coordinate mapping; the output (x2, y2) is then used as the final position of the peak. Using the excavator's coordinates as the origin (0,0), calculate the straight-line distance L1 based on the final position coordinates (x2,y2) of the wave crest; Methods for obtaining the slope angle of a wave crest from its final position include: Centered on the final position of the wave peak, a rectangular calculation area is formed by extending towards the excavator. The length of the rectangular calculation area is set along the slope extension direction, and the width is set perpendicular to the slope extension direction. From the 3D point cloud of the material pile acquired by the lidar, point clouds whose coordinates fall within the rectangular calculation area are selected to form a local point cloud subset. The local point cloud subset is denoised to remove isolated points and retain effective point clouds that can reflect the surface state of the material pile slope. The denoised effective point clouds are subjected to plane fitting to obtain a fitting plane that matches the surface morphology of the material pile slope. The angle between the fitting plane and the horizontal plane is calculated, and this angle is the slope angle of the corresponding slope area of ​​the material pile. During the excavation process, the image acquisition device transmits excavation images in real time for remote manual monitoring.

5. The material extraction method based on image recognition according to claim 2, characterized in that: The two buckets are a first bucket and a second bucket, which together form a bucket assembly. The back of the first bucket is arranged in a straight line, while the back of the second bucket is arranged in an arc shape.

6. The material extraction method based on image recognition according to claim 5, characterized in that: The bucket assembly also includes: A first upper arm and a second upper arm, wherein the first upper arm is mounted on the first bucket and the second upper arm is mounted on the second bucket, and the first upper arm and the second upper arm are hinged to each other; The support frame has a hinge point where the first upper arm and the second upper arm are hinged to each other, which is rotatably connected to the inner side of the support frame via a rotating shaft. A first hydraulic cylinder and a second hydraulic cylinder, wherein the cylinder end of the first hydraulic cylinder is hinged to the inner top side of the support frame, and the telescopic end is hinged to the upper end of the first upper arm; the cylinder end of the second hydraulic cylinder is hinged to the inner top side of the support frame, and the telescopic end is hinged to the upper end of the second upper arm; and two pressure sensors are provided, which are respectively installed at the pressure measuring ports of the first hydraulic cylinder and the second hydraulic cylinder. A connecting frame, the front end of which is rotatably connected to the support frame, and the rear end of which is rotatably connected to the excavator's boom; The third hydraulic cylinder has its cylinder end hinged to the inner side of the top of the connecting frame, and its telescopic end hinged to the outer side of the support frame. The control unit is connected to and controls the excavator arm, the first hydraulic cylinder, the second hydraulic cylinder, and the third hydraulic cylinder. The control unit drives the opening and closing of the first bucket and the second bucket by controlling the extension and retraction of the first hydraulic cylinder and / or the second hydraulic cylinder. The control unit adjusts the orientation of the first bucket and the second bucket by controlling the extension and retraction of the third hydraulic cylinder.

7. The material extraction method based on image recognition according to claim 6, characterized in that: The first mining mode includes the following steps: S11. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to open the first bucket and the second bucket to the maximum angle, adjusts the action of the digging arm so that the back of the first bucket is in close contact with the inner wall of the material pool, and drives the entire bucket assembly to move vertically downward so that the first bucket and the second bucket are inserted into the material pile. S12. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to close the first bucket and the second bucket together, and then controls the excavator's arm to pull out the bucket assembly to complete the digging. In step S11, when the bucket assembly moves downward, if it is determined that the bucket has touched the bottom, the downward movement of the bucket is stopped. Then, in step S12, during the process of the first bucket and the second bucket closing with each other, the bucket lips of the first bucket and the second bucket are ensured to be in contact with the inner bottom surface of the material pool.

8. The material extraction method based on image recognition according to claim 7, characterized in that: The second mining mode includes the following steps: S21. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to open the first bucket and the second bucket to the maximum angle, and adjusts the angle of the bucket assembly by the third hydraulic cylinder so that the bucket lips of the first bucket and the second bucket face the slope closer to the excavator. The control unit controls the arm so that the bucket lips of the first bucket and the second bucket are inserted into the slope facing the slope closer to the excavator. S22. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to close the first bucket and the second bucket together, and then controls the excavator's arm to pull out the bucket assembly to complete the digging.

9. The material extraction method based on image recognition according to claim 7, characterized in that: The laser radar defines the wave peak as an area with a relative height ≥ 0.5m or a slope angle > 30°. The relative height is the difference between the overall average height Havg of the stockpile and the height of the target stockpile. The excavation method further includes: if no wave peak is detected, the control unit controls the excavator to excavate in place; for areas beyond the effective excavation width D of the bucket, the following steps are used for excavation: S311. The control unit controls the first hydraulic cylinder and / or the second hydraulic cylinder to open the first bucket and the second bucket to the maximum angle. The angle of the bucket assembly is adjusted by the extension and retraction of the third hydraulic cylinder so that the bucket lips of the first bucket and the second bucket face the surface of the material pile. The control unit controls the digging arm so that the bucket lips of the first bucket and the second bucket are inserted into the material pile at a vertical angle. S312. The control unit controls the first bucket and the second bucket to close together, and then controls the excavator's arm to pull out the bucket assembly to complete the digging. For areas within the effective digging width D of the bucket, the first digging mode is used for digging.

Images