A three-dimensional scanning-based automatic slope excavation method and system and a storage medium thereof

Abstract

The application relates to the technical field of automatic control of engineering slope construction, and discloses a slope automatic excavation method and system based on three-dimensional scanning and a storage medium thereof, which solves the technical problems that, in the prior art, a slope scanning system and a digger control system adopt independent coordinate bases, coordinate drift is easily caused by equipment vibration and environmental interference after static calibration, and overbreak and underbreak errors are difficult to control; a digger track planning does not fully combine the kinematic characteristics of the digger, simple point control is mostly adopted, and motion dead points and track impact are easily caused; and a digger posture deviation in a construction process cannot be dynamically corrected. The application comprises the following steps: S1, calibrating points are arranged; S2, coordinate values of the calibration points in corresponding coordinate systems are obtained; S3, a coordinate conversion matrix is solved; S4, slope point cloud processing and overbreak and underbreak deviation analysis are performed; S5, excavation track planning and excavation control are performed; and S6, dynamic iterative correction and completion detection are performed. According to the above technical scheme, the automatic slope excavation precision is improved.

Description

Technical Field

[0001] This invention relates to the field of automated control technology for engineering slope construction, and more specifically, to an automatic slope excavation method, system, and storage medium based on three-dimensional scanning. Background Technology

[0002] Engineering slope construction includes precise slope excavation operations in infrastructure construction such as roads, water conservancy, and mines. The automatic slope excavation method proposed in this application is particularly suitable for unmanned construction sites under high and steep slopes and complex geological conditions.

[0003] Currently, slope excavation operations still rely primarily on manual layout and experience-based operation by excavator operators, resulting in low construction efficiency, poor excavation accuracy, and high safety risks. While some automated excavation solutions incorporate 3D scanning technology, they still have significant drawbacks: First, the slope scanning system and excavator control system use independent coordinate references, which, after static calibration, are prone to coordinate drift due to equipment vibration and environmental interference. This leads to inaccurate matching between scanned data and actual excavator movements, making it difficult to control over- and under-excavation errors. Second, excavator trajectory planning does not fully incorporate its own kinematic characteristics, often employing simple point-to-point control, which easily results in motion dead spots and trajectory impacts, affecting construction stability. Third, the lack of a real-time attitude feedback mechanism makes it impossible to dynamically correct excavator attitude deviations during construction, hindering the achievement of closed-loop control. Summary of the Invention

[0004] To address the technical problems raised in the background section, this invention aims to disclose and protect a method, system, and storage medium for automatic slope excavation based on three-dimensional scanning. This invention provides the following technical solution: An automated slope excavation method based on three-dimensional scanning, characterized by the following steps: S1. Setting up calibration points: Set up m ground calibration points in the construction area, where m≥3; and set up n characteristic calibration points on the excavator body, where n=2. S2. Obtain the coordinate values ​​of each calibration point in the corresponding coordinate system: S2-1. Use a total station to obtain the first coordinate values ​​of m ground calibration points in the engineering geodetic coordinate system; S2-2. Based on the rigid installation positions of n feature calibration points on the excavator body, the second coordinate value of the feature calibration points in the excavator body coordinate system is obtained in advance and remains unchanged. S2-3. Use a slope scanner to scan m ground calibration points and n feature calibration points to obtain their third coordinate values ​​in the scanner coordinate system. S3. Solve for the coordinate transformation matrix: S3-1. Based on the second and third coordinate values ​​corresponding to the n feature calibration points, solve for the first coordinate transformation matrix between the excavator body coordinate system and the scanner coordinate system; S3-2. Based on the first and third coordinate values ​​corresponding to m ground calibration points, solve for the second coordinate transformation matrix between the scanner coordinate system and the engineering geodetic coordinate system. S3-3. The slope scanner scans at a preset frequency. After each scan, the first coordinate transformation matrix and the second coordinate transformation matrix are recalculated, and the transformation relationship between the coordinate systems is updated in real time. S4. Slope point cloud processing and over- and under-excavation deviation analysis: S4-1. Use a slope scanner to perform three-dimensional laser scanning on the excavated area and collect the original point cloud data of the slope. S4-2. Preprocess the original point cloud data of the slope and construct a three-dimensional model of the actual slope. S4-3. Register and compare the actual slope 3D model with the pre-stored ideal slope model, divide the under-excavation area, and calculate the over-excavation and under-excavation amount at the corresponding location. S5. Excavation trajectory planning and excavation control: S5-1. Based on the first coordinate transformation matrix and the second coordinate transformation matrix, transform the spatial coordinates of the under-excavation area in the engineering geodetic coordinate system to the excavator body coordinate system; S5-2. Using the excavator DH parameter model, inverse kinematics is solved to transform the coordinates of the under-excavated area in the excavator body coordinate system into the target angles of each joint of the excavator and the target displacements of the cylinders. Fifth-order polynomial interpolation is used to generate a smooth excavation trajectory, and joint rotation angles and cylinder stroke constraints are combined to avoid motion dead points. S5-3. The position sensors of each axis of the excavator provide real-time feedback on the actual angle of the joints and the displacement data of the cylinders. The control and data processing unit compares the actual posture with the theoretical posture, corrects the trajectory deviation caused by structural deformation and load changes, and drives the excavator to work according to the excavation trajectory. S6. Dynamic Iterative Correction and Completion Detection: S6-1. After each section of slope excavation is completed, steps S4-S5 are executed repeatedly to refresh the actual slope 3D model and iteratively correct the subsequent excavation trajectory, thereby achieving closed-loop control of scanning-analysis-planning-control-feedback. S6-2. After the slope excavation is completed, a slope scanner is used to conduct a comprehensive scan and inspection of the entire slope area, generate an excavation quality report, and verify whether the slope elevation, slope ratio, and slope toe location meet the design and construction standards.

[0005] The present invention further specifies that: a third coordinate transformation matrix from the excavator body coordinate system to the engineering geodetic coordinate system is obtained by combining the first coordinate transformation matrix and the second coordinate transformation matrix, and the third coordinate transformation matrix is ​​updated synchronously with each scan.

[0006] The present invention further specifies that: based on the third coordinate transformation matrix, a mapping relationship is established between the excavator body coordinate system and the engineering geodetic coordinate system, so as to transform the target position of the bucket in the geodetic coordinate system to the excavator body coordinate system, so as to provide the DH-kinematic model for inverse kinematic solution.

[0007] The present invention further specifies that: when performing the inverse kinematics solution, the control and data processing unit limits the maximum joint rotation angle and the hydraulic cylinder extension and retraction stroke threshold to eliminate motion dead points; during the fifth-order polynomial interpolation planning of the excavation trajectory, the joint movement speed and acceleration upper limit are set to avoid hydraulic cylinder start-stop impact and improve the stability of excavation operation.

[0008] The present invention further specifies that the ground calibration point is a reflective target identified by the total station; The feature calibration point is a spherical component or a cube component, and the slope scanner extracts the third coordinate value of the feature calibration point by recognizing the outline of the spherical component or the cube component. An automatic slope excavation system based on three-dimensional scanning, which executes the aforementioned automatic slope excavation method, includes a benchmark calibration module, a slope scanning module, an excavator body module, and a control and data processing unit. The benchmark calibration module includes m ground calibration points and n feature calibration points arranged on the excavator body; The slope scanning module is a fixed three-dimensional laser slope scanner, used to collect slope point cloud data and identify ground calibration points and feature calibration points; The excavator body module is equipped with position sensors for each axis, and the excavator body module has a pre-stored DH-parameter kinematic model; the position sensors for each axis are used to collect the actual joint angles and cylinder displacements in real time. The control and data processing unit is configured to: solve multiple sets of coordinate transformation matrices, process point cloud data to obtain over- and under-excavation amounts; complete inverse kinematics solution based on the DH-parameter model and generate excavation trajectory using fifth-order polynomial interpolation; receive data from sensor feedback to dynamically correct the excavation trajectory; and generate an excavation quality report after excavation is completed.

[0009] The present invention further specifies that: m ground calibration points are set up in the construction area, where m≥3; and n feature calibration points are arranged on the excavator body, where n=2. A computer storage medium storing a computer program that, when the computer program is run, executes the aforementioned automatic slope excavation method.

[0010] In summary, the present invention has the following beneficial effects: (1) Improve excavation accuracy: Relying on the ground calibration point and the excavator body feature calibration point to solve two sets of coordinate transformation matrices in real time, eliminate the coordinate drift caused by equipment vibration and track slippage; Combined with the inverse solution of DH-parameter model and real-time feedback of sensor attitude, the over-excavation and under-excavation error of the slope is controlled within ±5cm, and the slope ratio error is ≤1%.

[0011] (2) Improve excavation stability: Based on the DH-kinematic model of the excavator and using fifth-order polynomial interpolation for trajectory planning, avoid dead points in motion, constrain joint movement speed and acceleration, reduce the impact of cylinder start-stop, and improve the shaking problem in the excavation process.

[0012] (3) Achieve closed-loop automatic control: Construct a closed-loop control process of “scan-analysis-planning-control-feedback” to dynamically compensate for attitude deviations caused by frame deformation and excavation load changes, thus getting rid of the traditional open-loop control mode.

[0013] (4) Improve construction efficiency and operational safety: Eliminate the steps of manual on-site layout and manual re-measurement, and improve construction efficiency by more than 30% compared with manual excavation; achieve unmanned excavation of high and steep slopes, avoid workers working on dangerous slopes, and reduce the risk of safety accidents.

[0014] (5) Strong adaptability to working conditions: By adjusting the scanning frequency of the scanner and the fifth-order polynomial interpolation parameters, it can adapt to different geological conditions and slope excavation conditions with different slope ratios.

[0015] (6) Digital traceability of construction process: The control unit saves point cloud data, excavation trajectory, over-excavation and under-excavation data and quality acceptance report throughout the process, which is convenient for later project verification. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the slope engineering construction site, as well as a schematic diagram of the ground marking points and feature marking points; Figure 2 This diagram illustrates the transformation logic between the three coordinate systems, and the schematic diagram illustrating the matrix acquisition logic for obtaining the first and second coordinate transformation matrices. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0019] An automated slope excavation method based on 3D scanning addresses three inherent shortcomings in existing automated slope excavation technologies: 1) The slope scanning system and the excavator control system use independent coordinate references. After static calibration, coordinate drift is easily caused by equipment vibration and environmental interference, which makes it difficult to accurately match the scanning data with the actual excavator action and make it difficult to control over-excavation and under-excavation errors. 2) Traditional excavator excavation only uses simple point-to-point control, without taking into account the kinematic constraints of the excavator's own multi-joint kinematics, which easily leads to dead points in motion, sudden trajectory changes and impacts, resulting in poor construction stability; 3) Traditional technology lacks real-time attitude feedback and dynamic correction mechanisms, and is an open-loop control that cannot compensate for construction deviations in real time, resulting in low excavation accuracy and poor consistency.

[0020] This invention achieves unmanned, precise excavation under steep slopes and complex geological conditions through multi-benchmark calibration, real-time updating of dual transformation matrices, inverse kinematics optimization using the DH kinematic model, smooth trajectory planning using a fifth-order polynomial, and real-time closed-loop feedback correction from sensors. The technical solution of this invention will be described in more detail below.

[0021] Firstly, during the initial construction phase, at least three ground calibration points need to be established in the construction area, and two feature calibration points need to be placed on the excavator itself. Firstly, the ground calibration points utilize a dedicated reflective target for a total station. This target has high reflectivity, allowing for precise measurement by the total station. Furthermore, its regular shape and clear point cloud features enable accurate identification of its outline by a 3D laser slope scanner. Secondly, the excavator's feature calibration points use standard spherical or cubic components, preferably a 10cm diameter solid sphere. This ensures no obstructions from sharp edges and a regular point cloud outline, forming a unique and clear feature outline in the slope scanner's point cloud data, avoiding interference from weeds, soil, and equipment structure in terms of identification accuracy.

[0022] Regarding the rules for setting up calibration points, combined with Figure 1As shown, it should also be noted that in this embodiment, three ground calibration points are preferably evenly distributed in the slope construction area. The three ground calibration points are set in a triangle within the slope operation area, with no obstruction of sight or soil, ensuring that the 3D laser slope scanner can scan the entire area and the total station can measure through the line of sight. At the same time, n=2 feature calibration points are rigidly fixedly installed on the top of the excavator cab, symmetrically arranged front and back, and fixed with bolts after installation, ensuring no displacement or loosening throughout the construction process.

[0023] After calibration, the coordinate values ​​of the three coordinate systems are obtained and combined with... Figure 2 As shown, the three coordinate systems are the engineering geodetic coordinate system, the scanner coordinate system, and the excavator body coordinate system. Correspondingly, the coordinates of the ground calibration points and feature calibration points are the first coordinate values ​​in the engineering geodetic coordinate system, the third coordinate values ​​in the scanner coordinate system, and the second coordinate values ​​in the excavator body coordinate system. A detailed explanation follows.

[0024] In order to obtain the coordinates (first coordinate value) in the engineering geodetic coordinate system, in this embodiment, a high-precision total station in the prior art is used to measure the three ground calibration points one by one to obtain the accurate three-dimensional coordinates of each ground calibration point in the unified engineering geodetic coordinate system of the construction site. These coordinates are the true absolute coordinates of the project and are the global reference of the entire construction system, which is fixed and unchanging.

[0025] It should be noted that this embodiment does not mention using a high-precision total station (in the prior art) to measure the coordinates of the two feature calibration points on the excavator body. This is because, during excavator operation, the excavator is in motion. Since the total station's measurement principle relies on light reflection, it cannot accurately measure the three-dimensional coordinates of the two feature calibration points in the unified engineering geodetic coordinate system of the construction site. Coordinate transformation, which will be discussed later, is the only option.

[0026] To obtain the coordinates (second coordinate values) in the excavator's body coordinate system, in this embodiment, an excavator body coordinate system is pre-established, with the excavator's rotation center as the origin, the excavator's forward direction as the X-axis, the transverse direction as the Y-axis, and the vertical direction as the Z-axis. Since the two feature calibration points are rigidly fixed to the top of the excavator's cab and have no relative displacement with the excavator's slewing platform, the three-dimensional coordinates of the two feature calibration points in the excavator's body coordinate system are fixed constants and do not change throughout the entire process after factory calibration, requiring no recalibration.

[0027] It should be noted that in this embodiment, the coordinates of the three ground calibration points in the excavator body coordinate system are not mentioned, and there is no need to convert these coordinates later, because the coordinates of the three ground calibration points in the excavator body coordinate system have no practical significance.

[0028] To obtain the coordinates (third coordinate value) in the scanner coordinate system, in this embodiment, a fixed 3D laser slope scanner is installed in a location with an open field of view in the construction area. The 3D laser slope scanner establishes its own independent scanner coordinate system (for example, with the center of the slope scanner lens as the origin). After the slope scanner is started, it performs a full-area scan of the construction area and simultaneously collects the real-time 3D coordinates of 3 ground calibration points and 2 excavator feature calibration points in the slope scanner's own coordinate system to form the original scan coordinate data.

[0029] This invention overcomes the shortcomings of traditional techniques that require "one-time static calibration and fixed parameters throughout," achieving high-frequency real-time updates of the dual transformation matrix and completely eliminating coordinate drift problems. The specific implementation process is as follows: Based on two excavator feature calibration points, namely "fixed body coordinates (second coordinate value)" and "real-time scanning coordinates of the slope scanner (third coordinate value)," a unique first coordinate transformation matrix is ​​obtained through the least squares algorithm. This matrix includes spatial translation, rotation, and scaling parameters, enabling precise mutual transformation between the excavator body coordinate system and the scanner coordinate system. In other words, the first coordinate transformation matrix is ​​used to solve for (excavator body coordinate system ⇋ scanner coordinate system).

[0030] Based on three ground calibration points—"high-precision total station measured geodetic coordinates (first coordinate value)" and "scanner real-time scanning coordinates (third coordinate value)"—the transformation relationship between the scanner coordinate system and the construction site geodetic coordinate system is obtained through point cloud registration and coordinate calculation algorithms. This unifies all scanning data from the slope scanner to the actual engineering benchmark. In other words, the transformation is solved using the second coordinate transformation matrix (scanner coordinate system ⇌ engineering geodetic coordinate system): The third coordinate transformation matrix is ​​generated by combining the first and second coordinate transformation matrices. This matrix directly maps the excavator's coordinate system to the engineering geodetic coordinate system. This matrix serves as the core conversion link of the system, directly converting any geodetic coordinate location on the construction site (mainly the excavator's bucket) into a coordinate system location that the excavator can recognize, providing a benchmark for subsequent DH kinematic model solutions.

[0031] Real-time dynamic update mechanism: The present invention sets a preset scanning frequency (preferably 10Hz) for the slope scanner. After each scan to collect point cloud data, the three sets of coordinate transformation matrices are re-solved and updated to compensate for coordinate deviations caused by equipment vibration, environmental interference, and body displacement in real time. The entire process maintains accurate alignment of multiple coordinate systems, fundamentally solving the defects of coordinate drift and data mismatch in traditional technologies.

[0032] Based on the aforementioned initialization configuration, the above initialization configuration is applied to the slope excavation process. After a certain period of slope excavation, the current status of the slope is scanned and deviation analysis is carried out to accurately identify the remaining excavation volume. Based on the accurately identified remaining excavation volume, excavation continues until the excavation operation is completed.

[0033] The specific steps are as follows: Raw point cloud data acquisition: A 3D laser slope scanner is used to perform a full-coverage scan of the current slope area to be excavated, and high-density raw point cloud data of the slope surface, soil outline, and topographic relief are acquired.

[0034] Point cloud preprocessing and real-world modeling: The control and data processing unit performs noise reduction, redundancy removal, ground fitting, and cavity repair preprocessing on the original point cloud data, eliminating construction dust, floating debris, and long-distance interference point clouds, retaining the real slope topography data, and automatically constructing a three-dimensional model of the actual slope that is completely consistent with the site.

[0035] Model registration and deviation calculation: The system pre-stores an ideal 3D slope design model (including design slope ratio, design elevation, slope toe location, and slope profile parameters) provided by an engineering design institute. It then performs a global registration and comparison between the actual slope model and the ideal slope model, calculating spatial deviations point by point. Areas with a deviation greater than 0 are identified as under-excavation areas (requiring excavation), while areas with a deviation less than 0 are identified as over-excavation areas. The system accurately outputs the over-excavation and under-excavation amounts and the coordinate set of the under-excavation range for each location, providing data support for subsequent trajectory planning.

[0036] Regarding subsequent trajectory planning, this invention specifically addresses the shortcomings of traditional technologies, such as "simple point-to-point control, susceptibility to jamming, and susceptibility to impact," by implementing intelligent trajectory planning based on the actual mechanical characteristics of excavators. The specific implementation method is as follows: Coordinate system transformation of target coordinates. The coordinates of the under-excavated area identified by the system are in the engineering geodetic coordinate system, while the DH kinematic model only identifies the coordinates in the excavator body coordinate system. Therefore, by using the first, second, and third coordinate transformation matrices updated in real time, all under-excavated target points in the geodetic coordinate system are accurately transformed to the excavator body coordinate system, achieving a unified reference between the designed excavation location and the excavator motion model.

[0037] Inverse kinematics solution using the DH parameter model. The excavator is a multi-joint, serially connected mechanical structure, comprising three core motion joints: the boom, arm, and bucket. Each joint has fixed mechanical travel and angular limits. This invention pre-stores a DH parameter model of the entire excavator, which accurately records the length of each joint link, hinge position, and motion constraint range. The converted coordinates of the under-excavated area are input into the DH parameter model, and through inverse kinematics solution, the three-dimensional target position of the bucket is transformed into the target joint angles of the boom, arm, and bucket, and the target extension and retraction displacements of the hydraulic cylinders.

[0038] It should be noted that the DH parameter model itself is a prior art. In this embodiment, the DH parameter model is used to realize parameter transformation and to transform the coordinates into target joint rotation angles of the boom, arm, and bucket and target extension and retraction displacement parameters of the hydraulic cylinder. This can be done according to the design of those skilled in the art.

[0039] Dead-point elimination. Traditional point control only focuses on the endpoint coordinates, which easily leads to situations where joint angles exceed mechanical limits or cylinder strokes exceed limits, resulting in unsolvable inverse kinematics solutions and excavator jamming (dead-point elimination). This invention, during the solution process, pre-sets the maximum and minimum angle thresholds for each joint and the cylinder extension / retraction stroke thresholds, automatically eliminating unsolvable and limit-exceeding points, and replanning feasible paths to completely avoid the dead-point elimination problem.

[0040] It should be noted that path planning based on the starting point and the destination is a known technology in the prior art. The focus of this embodiment is to check the intermediate trajectory points in the path planning of the prior art. The check is based on whether the excavator can reach each intermediate trajectory point. If it cannot reach the destination, the intermediate trajectory point is deleted and the path planning is re-formulated.

[0041] The advantage of setting up the inspection steps in this way is that if the excavator cannot reach the preset intermediate trajectory point, the excavation shape will definitely have a deviation, which will result in a large difference in the actual three-dimensional model of the slope obtained by scanning, poor quality, and affect the overall slope excavation quality.

[0042] Furthermore, traditional excavation methods only employ two-point linear control, resulting in sudden speed changes during cylinder start-stop, causing severe hydraulic shocks and machine vibration. This invention utilizes a fifth-order polynomial interpolation algorithm to generate a massive number of continuous intermediate trajectory points between the bucket's start and end points. Simultaneously, it limits the maximum speed and acceleration of joint movements, achieving uniform, smooth, and continuous bucket movement without sudden changes or impacts, significantly improving excavation stability and slope formation quality.

[0043] It should be noted that the fifth-order polynomial smooth trajectory interpolation algorithm is an existing technology. This embodiment is based on the algorithm to interpolate and generate a large number of continuous intermediate trajectory points between the start and end points of the bucket, thereby shortening the distance between adjacent trajectory points and improving excavation stability.

[0044] Real-time attitude closed-loop correction. Each joint of the excavator is equipped with a high-precision position sensor, which collects the actual rotation angle and actual displacement of each joint in real time throughout the construction process, and feeds it back to the control and data processing unit. The control and data processing unit compares the actual attitude data collected by the sensors with the theoretical attitude data calculated by the DH model in real time. For trajectory deviations caused by frame compression deformation, digging load changes, and oil temperature changes, it dynamically corrects the subsequent joint control parameters, compensates for excavation errors in real time, and ensures that the bucket operates strictly according to the planned trajectory.

[0045] In other words, when the chassis is subjected to pressure and sinking, when excavating soil and rocks under load, or when the hydraulic fluid stiffness changes due to oil temperature, the actual position of the bucket will deviate from the preset trajectory. After identifying the attitude difference, the control system will synchronously adjust the target angles of each joint and the extension and retraction of the cylinders to compensate in the opposite direction. For example, when excavating hard soil, the chassis is subjected to downward pressure under load, and the entire chassis sinks. After the system detects that the actual elevation of the bucket is lower than the theoretical elevation, it automatically adjusts the target angles of the boom and arm joints to raise the bucket position and offset the sinking caused by the chassis settlement. This is a compensation for the excavator's own performance to avoid affecting the excavation quality, that is, to improve the reliability of the excavator itself.

[0046] Therefore, a closed-loop construction system of "scanning-analysis-planning-control-feedback" was constructed in this implementation to solve the defect that traditional open-loop control cannot dynamically correct deviations.

[0047] In addition, this embodiment also includes the following.

[0048] Segmented Iterative Correction. The slope excavation adopts a segmented operation mode. After each segment of slope excavation is completed, the system automatically and cyclically executes point cloud scanning, model updating, deviation analysis, and trajectory planning processes, refreshing the actual slope 3D model in real time, and iteratively correcting the subsequent excavation trajectory based on the latest slope topography to avoid error accumulation and achieve dynamic closed-loop control.

[0049] Full-area completion inspection. After the overall slope excavation is completed, the slope scanner performs a full-coverage high-precision scan of the entire slope area, reconstructing the final 3D model of the slope. The system automatically compares the results with the design model, verifying core parameters such as slope elevation, overall slope ratio, slope toe line, and slope surface flatness, and automatically generates a digital excavation quality report. The construction accuracy of this invention can control over-excavation and under-excavation errors within ±5cm and slope ratio errors ≤1%, fully meeting the requirements of high-standard infrastructure construction.

[0050] The above provides a detailed description of the automatic slope excavation method. In this embodiment, an automatic slope excavation system is also provided to execute the aforementioned automatic excavation method, specifically comprising four core modules: a benchmark calibration module, a slope scanning module, an excavator body module, and a control and data processing unit.

[0051] The benchmark calibration module includes no fewer than 3 ground reflective target calibration points and 2 excavator rigid fixed feature calibration points, constructing a multi-dimensional, real-time calibrable construction benchmark system to provide a unique feature reference for multi-coordinate system transformation.

[0052] Slope scanning module: It adopts a fixed high-precision 3D laser slope scanner, which is responsible for high-frequency acquisition of slope point cloud data and identification of the characteristic coordinates of various calibration points, providing raw data for model construction, matrix solving and deviation analysis.

[0053] Excavator body module: Equipped with multi-axis high-precision position sensors and built-in whole machine DH parameter kinematic model, it can provide real-time feedback on joint posture, receive control commands to execute excavation actions, and has the mechanical control capabilities of autonomous dead point avoidance and smooth movement.

[0054] Control and Data Processing Unit: As the core of the system, it integrates the full-process algorithms of matrix solving, point cloud processing, model comparison, DH inverse solution, trajectory planning, closed-loop correction, and quality inspection, realizing fully automated operation and control without manual intervention.

[0055] This embodiment also provides a computer-readable storage medium storing a computer program. When the processor runs, the program can completely execute the steps of any of the above-mentioned automatic slope excavation methods in this embodiment, realizing the full-process automated control of slope scanning calibration, deviation analysis, trajectory planning, closed-loop correction, and quality inspection. It can be mounted on various construction control equipment such as industrial controllers, industrial control computers, and embedded terminals.

[0056] Compared to existing technologies, the actual engineering construction results demonstrate that the final results achieve: significantly improved construction accuracy, no need for manual surveying and layout, unmanned operation in high-risk areas, and an increase in construction efficiency of over 30%. At the same time, the construction data is traceable throughout the entire process, adaptable to various complex geological and slope conditions, and has extremely high practicality and engineering value.

[0057] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for automatic slope excavation based on three-dimensional scanning, characterized in that, Includes the following steps: S1. Setting up calibration points: Set up m ground calibration points in the construction area, where m≥3; and set up n characteristic calibration points on the excavator body, where n=2. S2. Obtain the coordinate values ​​of each calibration point in the corresponding coordinate system: S2-1. Use a total station to obtain the first coordinate values ​​of m ground calibration points in the engineering geodetic coordinate system; S2-2. Based on the rigid installation positions of n feature calibration points on the excavator body, the second coordinate value of the feature calibration points in the excavator body coordinate system is obtained in advance and remains unchanged. S2-3. Use a slope scanner to scan m ground calibration points and n feature calibration points to obtain their third coordinate values ​​in the scanner coordinate system. S3. Solve for the coordinate transformation matrix: S3-1. Based on the second and third coordinate values ​​corresponding to the n feature calibration points, solve for the first coordinate transformation matrix between the excavator body coordinate system and the scanner coordinate system; S3-2. Based on the first and third coordinate values ​​corresponding to m ground calibration points, solve for the second coordinate transformation matrix between the scanner coordinate system and the engineering geodetic coordinate system. S3-3. The slope scanner scans at a preset frequency. After each scan, the first coordinate transformation matrix and the second coordinate transformation matrix are recalculated, and the transformation relationship between the coordinate systems is updated in real time. S4. Slope point cloud processing and over- and under-excavation deviation analysis: S4-1. Use a slope scanner to perform three-dimensional laser scanning on the excavated area and collect the original point cloud data of the slope. S4-2. Preprocess the original point cloud data of the slope and construct a three-dimensional model of the actual slope. S4-3. Register and compare the actual slope 3D model with the pre-stored ideal slope model, divide the under-excavation area, and calculate the over-excavation and under-excavation amount at the corresponding location. S5. Excavation trajectory planning and excavation control: S5-1. Based on the first coordinate transformation matrix and the second coordinate transformation matrix, transform the spatial coordinates of the under-excavation area in the engineering geodetic coordinate system to the excavator body coordinate system; S5-2. Using the excavator DH parameter model, inverse kinematics is solved to transform the coordinates of the under-excavated area in the excavator body coordinate system into the target angles of each joint of the excavator and the target displacements of the cylinders. Fifth-order polynomial interpolation is used to generate a smooth excavation trajectory, and joint rotation angles and cylinder stroke constraints are combined to avoid motion dead points. S5-3. The position sensors of each axis of the excavator provide real-time feedback on the actual angle of the joints and the displacement data of the cylinders. The control and data processing unit compares the actual posture with the theoretical posture, corrects the trajectory deviation caused by structural deformation and load changes, and drives the excavator to work according to the excavation trajectory. S6. Dynamic Iterative Correction and Completion Detection: S6-1. After each section of slope excavation is completed, steps S4-S5 are executed repeatedly to refresh the actual slope 3D model and iteratively correct the subsequent excavation trajectory, thereby achieving closed-loop control of scanning-analysis-planning-control-feedback. S6-2. After the slope excavation is completed, a slope scanner is used to conduct a comprehensive scan and inspection of the entire slope area, generate an excavation quality report, and verify whether the slope elevation, slope ratio, and slope toe location meet the design and construction standards.

2. The automatic slope excavation method according to claim 1, characterized in that, The third coordinate transformation matrix is ​​obtained by combining the first coordinate transformation matrix and the second coordinate transformation matrix to the engineering geodetic coordinate system. The third coordinate transformation matrix is ​​updated synchronously with each scan.

3. The automatic slope excavation method according to claim 2, characterized in that, Based on the third coordinate transformation matrix, a mapping relationship is established between the excavator body coordinate system and the engineering geodetic coordinate system to transform the target position of the bucket in the geodetic coordinate system to the excavator body coordinate system, so as to provide the DH-kinematic model for inverse kinematics solution.

4. The automatic slope excavation method according to claim 1, characterized in that, During the inverse kinematics solution, the control and data processing unit limits the maximum joint rotation angle and the cylinder extension / retraction stroke threshold to eliminate motion dead points; during the fifth-order polynomial interpolation planning of the excavation trajectory, the joint movement speed and acceleration upper limits are set to avoid cylinder start-stop impact and improve the stability of excavation operations.

5. The automatic slope excavation method according to claim 1, characterized in that, The ground calibration point is the reflective target identified by the total station; The feature calibration point is a spherical component or a cube component, and the slope scanner extracts the third coordinate value of the feature calibration point by recognizing the outline of the spherical component or the cube component.

6. An automated slope excavation system based on three-dimensional scanning, characterized in that, The automatic slope excavation method according to any one of claims 1-5 includes a benchmark calibration module, a slope scanning module, an excavator body module, and a control and data processing unit. The benchmark calibration module includes m ground calibration points and n feature calibration points arranged on the excavator body; The slope scanning module is a fixed three-dimensional laser scanner, used to collect slope point cloud data and identify ground calibration points and feature calibration points; The excavator body module is equipped with position sensors for each axis, and the excavator body module has a pre-stored DH-parameter kinematic model; the position sensors for each axis are used to collect the actual joint angles and cylinder displacements in real time. The control and data processing unit is configured to: solve multiple sets of coordinate transformation matrices, process point cloud data to obtain over- and under-excavation amounts; complete inverse kinematics solution based on the DH-parameter model and generate excavation trajectory using fifth-order polynomial interpolation; receive data from sensor feedback to dynamically correct the excavation trajectory; and generate an excavation quality report after excavation is completed.

7. The automatic slope excavation system according to claim 6, characterized in that, Set up m ground calibration points in the construction area, where m≥3; and set up n feature calibration points on the excavator body, where n=2.

8. A computer storage medium storing a computer program, characterized in that, When the computer program is run, it performs the method according to any one of claims 1-5.

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