Slope three-dimensional deformation real-time monitoring method based on multi-laser scanning

Abstract

The invention relates to the technical field of slope engineering monitoring, and particularly discloses a slope three-dimensional deformation real-time monitoring method based on multi-laser scanning, which comprises the steps of monitoring system arrangement, reference coordinate system establishment, initial scanning and coordinate recording, real-time scanning and deviation correction, data analysis and early warning and the like. The core contribution of the slope three-dimensional deformation monitoring method is that a stable reference coordinate system with self-correction capability is established, and on the basis, the slope three-dimensional deformation monitoring method with high reliability, full coverage and real-time intelligent early warning is realized through multi-sensor fusion and intelligent data processing. The system mainly solves the problems of large systematic error and low reliability caused by unstable reference in the existing slope monitoring technology, and secondarily solves the technical problems of incomplete data caused by single view angle and weak early warning capability caused by low automation degree.

Description

Technical Field

[0001] This invention relates to the field of slope engineering monitoring technology, and in particular to a method for real-time monitoring of three-dimensional deformation of slopes based on multi-laser scanning. Background Technology

[0002] In the field of disaster monitoring, three-dimensional slope deformation monitoring is crucial for ensuring the safety of people and the stability of infrastructure. With the advancement of road, bridge, and mining construction, slope stability issues are becoming increasingly prominent. Real-time and accurate monitoring of slope three-dimensional deformation helps to identify potential geological hazards in advance, prevent landslides, debris flows, and other disasters, reduce economic losses, and ensure the long-term stable operation of projects.

[0003] Currently, slope monitoring technology has shifted from traditional manual monitoring to automated real-time monitoring. For example, Chinese invention patent CN104713491B discloses a "slope monitoring system capable of acquiring three-dimensional data of slope deformation." This system collects data through a laser rangefinder and image acquisition device, and performs coordinate transformation through an information processing device to obtain the three-dimensional deformation of the slope. However, this type of technology has the following limitations: First, the monitoring accuracy depends on the stability of the monitoring equipment and the target. Once the monitoring point used as the measurement benchmark shifts, it will introduce systematic errors that cannot be identified or corrected, seriously affecting the reliability of the monitoring data. Second, the system uses a single fixed-viewpoint sensor, which has blind spots in monitoring complex slope structures, making it difficult to obtain a comprehensive three-dimensional deformation field. In addition, the system lacks intelligent real-time data processing and early warning capabilities, and its level of automation is limited.

[0004] Therefore, there is an urgent need for a highly reliable three-dimensional deformation monitoring solution for slopes that can establish a stable benchmark, achieve multi-source data fusion, and have intelligent early warning capabilities. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention provides a real-time monitoring method for three-dimensional deformation of slopes based on multi-laser scanning. This method primarily addresses the problem of large errors and low accuracy in existing slope monitoring technologies due to systematic errors introduced by unstable benchmarks. It also addresses the technical problems of incomplete data caused by a single perspective and weak early warning capabilities due to low automation.

[0006] To solve the above problems, the technical solution adopted by the present invention is as follows: An embodiment of this application provides a real-time monitoring method for three-dimensional deformation of slopes based on multi-laser scanning, comprising the following steps: S1: Deploy the monitoring system and set up a set of reference targets outside the slope. The set of reference targets consists of four non-coplanar reference targets, namely the first reference target, the second reference target, the third reference target, and the fourth reference target. Avoid setting up multiple monitoring targets on the slope and install the scanner at a position that can observe all reference targets at the same time. S2: Initial scanning and coordinate recording. After the scanner is set up for the first time, an initial coordinate system is established by the scanner and the position of the reference target. The scanner simultaneously scans the reference target group and the monitoring target to obtain the initial position coordinates of the reference target group and the monitoring target.

[0007] S3: Establish a reference coordinate system. Calculate the initial coordinates of the center of the sphere composed of the reference target group using the initial position coordinates of the reference target group, and use the initial coordinates of the center of the sphere as the reference point to establish the reference coordinate system.

[0008] S4: Real-time scanning and deviation correction. The scanner synchronously scans the reference target group and the monitoring target at set time intervals. The first reference target is the reference target that generates the largest displacement. The registration algorithm is used to correct the coordinates of the first reference target after correction. Then, the current position deviation of the scanner is calculated. The target data is then corrected in the reference coordinate system using the current position deviation of the scanner.

[0009] S5: Data analysis and early warning. The data processing unit generates a cloud map of the absolute displacement field of the slope; sets thresholds for slope displacement and rate, and triggers an alarm when the limits are exceeded.

[0010] The registration algorithm described in step S4 uses the trilateration formula to first find the original coordinates of the reference point. Then, taking the original coordinates of the reference point as the origin and the distance from the initial position coordinates of the first reference target to the reference point as the radius, a sphere is obtained. The intersection of the line connecting the coordinates of the first reference target and the coordinates of the origin of the reference point with the sphere after calculating the displacement is obtained as the corrected coordinates of the first reference target.

[0011] The beneficial effects of this scheme are as follows: 1. This scheme corrects the coordinates of the benchmark target with the largest displacement in real time through a registration algorithm. Utilizing trilateration formulas and spherical geometry, it dynamically compensates for the displacement of the benchmark point. This correction reduces deviations caused by benchmark instability, avoids the accumulation of errors in the detection data, and reduces systematic errors. 2. The benchmark target group consists of four benchmark targets with different surfaces, forming a stable spatial reference frame. The registration algorithm corrects the benchmark target with the largest displacement, and combines other benchmark targets to provide auxiliary references, ensuring the stability of the benchmark coordinate system. Even if individual benchmark targets experience large displacements, the registration algorithm can correct them through the spherical model, preventing the entire system from failing, thereby improving the robustness and fault tolerance of the monitoring system. 3. The data corrected by the registration algorithm is used to generate slope displacement field cloud maps and trigger early warnings. Because the errors introduced by benchmark instability are minimized, the judgment of displacement and rate thresholds is more accurate, reducing the risk of false alarms or missed alarms, making the early warning system more reliable.

[0012] Furthermore, the initial coordinate system takes the location of the scanner as the origin, the projection direction of the line connecting the scanner and any reference target in the horizontal direction is the X-axis, and the X-axis is defined as the positive direction pointing to the first scanner; the opposite direction of the local gravitational acceleration is the Z-axis; the positive direction of the Y-axis strictly follows the right-hand rule.

[0013] Furthermore, the Z-axis of the reference coordinate system is a vertical line passing through the reference point, and the positive direction of the Z-axis is the opposite direction of the local gravitational acceleration; the X-axis is a horizontal straight line passing through the reference point, and the direction of the X-axis pointing to the first scanner is the positive direction; the Y-axis passes through the reference point and is orthogonal to both the X-axis and the Z-axis, and the positive direction of the Y-axis strictly follows the right-hand rule.

[0014] Furthermore, when only the first reference target is displaced, the registered algorithm is used to calculate the corrected coordinates of the first reference target using the following formula: Calculate the sphere containing the corrected first reference target A2:

[0015] In the formula: P0 is the initial coordinates of the reference point (PX, PY, PZ); A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA is the distance from P0 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target; Following the principle of minimizing adjustments, the coordinates of the first reference target A2 after correction are clearly defined:

[0016] In the formula: P0 is the initial coordinate of the reference point (PX, PY, PZ); A1 is the coordinate of the first reference target after displacement (A1X, A1Y, A1Z); A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA is the distance from P0 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target.

[0017] Furthermore, when all the reference target groups have undergone displacement, the registered algorithm is used to calculate the corrected coordinates of the first reference target using the following formula: The original coordinates of the benchmark points are verified using the trilateration formula, as follows:

[0018]

[0019]

[0020] In the formula: P1 is the coordinate of the reference point (PX1, PY1, PZ1) after the displacement is generated; B1 is the initial coordinate (BX1, BY1, BZ1) of the second reference target; C1 is the initial coordinate of the third benchmark target (CX1, CY1, CZ1). D1 is the initial coordinate (DX1, DY1, DZ1) of the fourth reference target; dB1 is the distance from P1 to B1 after the displacement is generated; dC1 is the distance from P1 to C1 after the displacement occurs; dD1 is the distance from P1 to D1 after the displacement occurs; At this point, the original coordinates P0 of the reference point have two solutions. The correct solution is the one that is closer to the origin of the first reference coordinate system 01. Calculate the sphere containing the corrected first reference target A2:

[0021] In the formula: P1 is the coordinate of the reference point (PX1, PY1, PZ1) after the displacement is generated; A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA1 is the distance from P1 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target; Using the principle of minimizing adjustments, the coordinates of the first reference target A2 after correction are determined:

[0022] In the formula: P1 represents the coordinates of the reference point (PX1, PY1, PZ1) after the displacement is generated. A1 is the coordinate of the first reference target after displacement (A1X, A1Y, A1Z); A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA1 is the distance from P1 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target.

[0023] Furthermore, in step S3, the scanner employs multiple scanners to simultaneously scan the slope from different angles, uses a data processing unit to achieve time synchronization, and finally synthesizes the final coordinates of the monitoring target through weighted averaging. By using multiple laser scanners to simultaneously scan the slope from different angles, and synthesizing more accurate monitoring target coordinates through coordinate transformation and data fusion, the comprehensiveness and accuracy of monitoring are improved.

[0024] Furthermore, the scanner data is processed by the data processing unit to generate a three-dimensional displacement vector of the monitoring target, and an absolute displacement field cloud map of the slope is constructed based on the vector. The data processing unit presets displacement and velocity thresholds. When the displacement or velocity of the monitoring target in the displacement field cloud map exceeds the threshold, an alarm signal output module is triggered to issue an alarm. The integrated data processing unit generates an absolute displacement field cloud map, sets displacement and velocity thresholds, and triggers an audible and visual alarm when the limits are exceeded, realizing fully automated monitoring from data acquisition and processing to early warning. Attached Figure Description

[0025] Figure 1 This is a system structure layout diagram of Embodiment 1 of the present invention.

[0026] Figure 2 This is a system structure layout diagram of Embodiment 2 of the present invention.

[0027] Figure 3 This is a schematic diagram of the original benchmark target of this invention.

[0028] Figure 4 This is a schematic diagram of the displacement of the first reference target in this invention.

[0029] Figure 5 This is a schematic diagram of the first reference target displacement correction of the present invention.

[0030] The reference numerals in the accompanying drawings include: reference point 00; first reference coordinate system 01; second reference coordinate system 02; First reference target 110; First reference target 111 after displacement; First reference target 112 after correction; Second benchmark target 12; Third benchmark target 13; Fourth benchmark target 14; Monitoring target 2; first scanner 31; second scanner 32; slope 4. Detailed Implementation

[0031] The following detailed description illustrates the specific implementation method: Example 1 This application provides a method for real-time monitoring of three-dimensional deformation of slopes based on multi-laser scanning, comprising the following steps: S1: Set up a monitoring system: Set up benchmark targets in four independent and relatively stable areas outside the slope. The benchmark target groups are not coplanar and constitute a benchmark target group; deploy multiple monitoring targets on the slope surface; install the scanner at a position that can observe all benchmark targets at the same time.

[0032] S2: Initial Scan and Coordinate Recording: After the first scanner 31 is initially set up, the location of the first scanner 31 is taken as the origin of the coordinate system. The projection direction of the line connecting the first scanner 31 and any reference target in the horizontal direction is the X-axis, and the direction pointing to the first scanner 31 is defined as the positive direction of the X-axis. The opposite direction of the local gravitational acceleration is the Z-axis. The positive direction of the Y-axis strictly follows the right-hand rule. The initial coordinate system is established, and the scanner simultaneously scans the reference target group and the monitoring target 2 to obtain the initial position coordinates of the reference target group and the monitoring target 2.

[0033] The right-hand rule states that when the four fingers of the right hand grasp from the positive X-axis to the positive Z-axis along the shortest path, the direction in which the thumb is extended is the positive Y-axis.

[0034] S3: Establish a reference coordinate system: Calculate the initial coordinates of the center of the sphere formed by the reference target group using the initial position coordinates of the reference target group, and use the initial coordinates of the center of the sphere as the reference point 00 to establish a reference coordinate system; the Z-axis of the reference coordinate system is a vertical line passing through the reference point 00, and the positive direction of the Z-axis is the opposite direction of the local gravitational acceleration; the X-axis is a horizontal straight line passing through the reference point 00, and the positive direction of the X-axis points from the reference point 00 to the direction of the projection point of the center point of the first scanner 31 on the horizontal plane during its initial setup; the Y-axis passes through the reference point 00 and is orthogonal to both the X-axis and Z-axis, and the positive direction of the Y-axis strictly follows the right-hand rule.

[0035] The initial position coordinates of the first scanner and the reference target group are known. The Z-axis of both the initial and reference coordinate systems is plumb; the positive X-axis is defined as the horizontal projection line pointing to the first scanner 31; and the Y-axis is determined using the right-hand rule. Therefore, when transforming between the initial and reference coordinate systems, only a simple translation vector and a rotation around the Z-axis need to be considered. The translation vector is defined as the distance from the origin of the initial coordinate system (scanner position) to the origin of the reference coordinate system (center reference point 00); the rotation angle is defined as the angle between the positive X-axis of the two coordinate systems after their origins overlap.

[0036] S4: Real-time scanning and deviation correction: The first scanner 31 synchronously scans the reference target group and the monitoring target 2 at a set time interval; the first reference target 111 is the reference target that generates the largest displacement. After correcting its coordinates using the registration algorithm, the coordinates of the first reference target 112 are obtained. Then, the current position deviation of the first scanner 31 is calculated. The data of the monitoring target 2 is corrected in the reference coordinate system using the current position deviation of the first scanner 31.

[0037] S5: Data Analysis and Early Warning: Generates a cloud map of the absolute displacement field of the slope using the data processing unit; sets thresholds for slope displacement and rate, and triggers an alarm when the limits are exceeded.

[0038] The real-time monitoring method for three-dimensional deformation of slopes based on multi-laser scanning requires a system including a set of reference targets, a data processing unit, and a laser scanner. The laser scanner is used to simultaneously scan the set of reference targets and the monitoring targets 2 deployed on the surface of slope 4. The data processing unit establishes a reference coordinate system by using the coordinates of the center of the reference target set (i.e., the coordinates of the reference point 00) and the position coordinates of the laser scanner. During the monitoring process, the current position deviation between the scanner and the reference target set is calculated based on the reference coordinate system. The current position deviation of the laser scanner is used to correct the monitoring data of the monitoring targets 2 in the reference coordinate system, thereby achieving the effect of accurately monitoring the three-dimensional deformation of slope 4.

[0039] Specifically, the reference targets are spherical structures, which are relatively regular and facilitate coordinate calculation and scanning identification. The reference target group is fixed to independent monitoring piers, which are set in four independent and relatively stable areas. The monitoring piers are made of cast concrete, possessing good stability and anti-interference capabilities, providing stable support for the reference target group. By placing the reference target group in four independent and relatively stable areas, the influence of slope deformation on the position of the reference target group can be reduced. Even if one reference target undergoes displacement, the impact on other reference targets can be minimized, thus ensuring the stability of the reference coordinate system.

[0040] Specifically, the data processing unit is a high-performance computer equipped with a large capacity of memory and a high-speed processor to meet the needs of data processing and computation.

[0041] Specifically, the first reference coordinate system 01 takes the center of the reference target group as the reference point 0O. The Z-axis is a vertical line passing through the reference point 0O, and the positive direction of the Z-axis is the opposite direction of the local gravitational acceleration. The X-axis is a horizontal straight line passing through the reference point 0O. The positive direction of the X-axis points from the reference point 0O to the direction of the projection of the center point of the first scanner 31 when it is first set up on the horizontal plane. That is, the X-axis only considers the horizontal relationship between the origin O and the scanner and ignores the elevation difference. The Y-axis passes through the reference point 0O and is orthogonal to both the X-axis and the Z-axis. The positive direction of the Y-axis strictly follows the right-hand rule: when the four fingers of the right hand grasp from the positive direction of the X-axis to the positive direction of the Z-axis along the shortest path, the direction that the thumb points is the positive direction of the Y-axis.

[0042] Specifically, the laser scanner can be a pulsed laser scanner, which determines the target's distance by emitting laser pulses towards the target and measuring the time from emission to return. This type of scanner features high scanning speed and a wide measurement range. Alternatively, a phase-type laser scanner can be used, which determines the target's distance by measuring the phase difference of the laser signal, offering higher measurement accuracy. The scanner is installed on the front or side of slope 4 to ensure simultaneous observation of all reference targets and all monitoring targets on slope 4.

[0043] After the first scanner 31 is installed in the predetermined position, when the first scanner 31 performs its first scan, the first reference coordinate system 01 is determined by the coordinate point of the first scanner 31 and the reference point 00, and the initial position coordinates of the first scanner 31 are recorded. The first scanner 31 is controlled to synchronously scan the reference target group and the monitoring target 2, and the initial position coordinates of the reference target group and the monitoring target 2 are obtained. Then, the first scanner 31 is used to synchronously scan the reference target group and the monitoring target at a set time interval.

[0044] During long-term scanning, the reference target group and the first scanner 31 may be displaced due to the influence of the surrounding environment. If the current position coordinates of the reference target group and the first scanner 31 are not corrected, it will affect the data of the monitoring target 2 deployed on the surface of the slope 4.

[0045] Therefore, when the first scanner 31 performs the nth scan, it obtains the current position coordinates of the reference target group and the monitoring target 2. Through the registration algorithm, the coordinates of the first reference target 11 that has generated displacement in the reference target group are corrected. Then, the current position coordinates of the first scanner 31 are calculated. By comparing the current position coordinates of the first scanner 31 with the initial position coordinates of the first scanner 31, the current position deviation of the first scanner 31 relative to the initial position coordinates of the first scanner 31 can be calculated. The current position deviation of the first scanner 31 is used to correct the data of the monitoring target 2 in the first reference coordinate system 01.

[0046] Specifically, the registration algorithm uses four non-coplanar reference targets, namely the first reference target 110, the second reference target 12, the third reference target 13, and the fourth reference target 14, to uniquely identify a sphere whose center is the reference point 00. After the first scan by the first scanner 31, the distances from the reference point 00 to the reference target group are fixed and known, and are denoted as dA, dB, dC, and dD, respectively, with dA=dB=dC=dD.

[0047] Registration Algorithm Case 1: Assume that only the first reference target 110 has been displaced. After the displacement, the coordinates of the first reference target 111 can be measured by the first scanner 31, while the coordinates of the other reference targets remain unchanged. Therefore, let the coordinates of the first reference target 111 be A0(AX,AY,AZ), the coordinates of the second reference target 12 be B0(BX,BY,BZ), the coordinates of the third reference target 13 be C0(CX,CY,CZ), and the coordinates of the fourth reference target 14 be D0(DX,DY,DZ).

[0048] Verify the original coordinates of reference point 00. Since the coordinates of the second, third, and fourth reference targets remain unchanged, and the distances from reference point 00 to these three points are known to be dB, dC, and dD, respectively, the coordinates P0(PX, PY, PZ) of reference point 00 are calculated through trilateration.

[0049] The trilateration formula is the intersection point of three spheres with the second, third, and fourth reference targets as centers and radii of dB, dC, and dD, respectively. The specific formula is as follows:

[0050]

[0051]

[0052] The original coordinates P0 of the reference point calculated using the trilateration formula have two solutions. The correct solution is determined based on the origin coordinates of the first reference coordinate system 01, i.e., the coordinates closer to the origin of the first reference coordinate system 01. This step is used to verify the accuracy of the original coordinates of reference point 00. The corrected coordinates A2(A2X, A2Y, A2Z) of the first reference target 112 are then calculated. The corrected coordinates from the original coordinates of reference point 00 to the corrected coordinates of the first reference target 112 must satisfy the following condition: the distance from the original coordinates of reference point 00 to the corrected coordinates of the first reference target 112 is equal to the known distance dA, i.e.:

[0053] Meanwhile, to minimize the adjustment range, the goal is to make A2 as close as possible to the coordinates A1(A1X, A1Y, A1Z) of the first reference target 111 after movement, while satisfying the aforementioned distance constraints. Therefore, coordinate A2 is the point on the sphere with reference point 00 as the center and dA as the radius that is closest to coordinate A1. The calculation formula is as follows:

[0054] After the adjustment is completed, the distance between the coordinates of the first reference target 110 and the corrected coordinates of the first reference target 112 is calculated. A critical value is defined for this distance. When the critical value is exceeded, it indicates that the reference coordinate system has been destroyed, and the measurement error will increase if the measurement continues.

[0055] Registration Algorithm Scenario 2: Assume that all four reference targets have undergone displacement, with the first reference target 110 experiencing the largest displacement of A1(A1X,A1Y,A1Z). At this time, the first scanner 31 can obtain the coordinates of the second reference target after displacement: B1(BX1,BY1,BZ1), the third reference target after displacement: C1(CX1,CY1,CZ1), and the fourth reference target after displacement: D1(DX1,DY1,DZ1). Through calculation, the distances from the initial reference point coordinates P0(PX,PY,PZ) to the three points after displacement are found to be dB1, dC1, and dD1, respectively. Then, the coordinates of the reference point after displacement, P1(PX1,PY1,PZ1), are generated through trilateration. Since the second, third, and fourth reference targets have undergone displacement, there is a distance between the coordinates of the reference point after displacement, P1, and the initial reference point, P0. A critical value is defined for this distance. When this critical value is exceeded, it indicates that the reference coordinate system has been destroyed, and if the measurement continues, the error will increase.

[0056] The implementation principle of this embodiment is as follows: by setting up a set of reference targets and a laser scanner, a first reference coordinate system 01 is established, and the coordinate A1 of the first reference target 111 after displacement is corrected by using the trilateration method and the principle of minimization adjustment, so as to reduce the systematic error of the monitoring data caused by the displacement of the reference target itself, thereby improving the monitoring accuracy.

[0057] Example 2 The difference between this embodiment and the above embodiments is that: in this embodiment, there are two or more scanners. Two scanners are listed for illustration. Specifically, there is a first scanner 31 and a second scanner 32. The first scanner 31 and the second scanner 32 establish corresponding first reference coordinate system 01 and second reference coordinate system 02, respectively, and achieve synchronous scanning through the data processing unit. The first reference coordinate system 01 and the second reference coordinate system 02 share the Z-axis. Therefore, the different reference coordinate systems only differ in the plane rotation angle. It is easy to convert the coordinates of the monitoring target 2 obtained by scanning the second reference coordinate system 02 to the first reference coordinate system 01. All position coordinate data of the monitoring target 2 are converted to the first reference coordinate system 01, which is beneficial for more intuitive analysis of position coordinate information.

[0058] Specifically, the first scanner 31 scans from the front of the slope 4, and the second scanner 32 scans from the side of the slope 4. This allows for more comprehensive information about the slope 4, improving monitoring accuracy. Data for the monitoring target 2 is acquired simultaneously by multiple scanners and converted to the first reference coordinate system 01. The final coordinates of the monitoring target 2 are then synthesized through weighted averaging. Combining the measurement results from multiple scanners further improves the accuracy of the monitoring data. The data processing unit generates a three-dimensional displacement vector for the monitoring target 2 and constructs an absolute displacement field cloud map of the slope based on the vector. This cloud map includes the spatial coordinate change trends of each monitoring target. Simultaneously, the data processing unit presets displacement and velocity thresholds. When the displacement or velocity of the monitoring target in the displacement field cloud map exceeds the threshold, an alarm signal output module is triggered. The alarm signal output module can be an audible and visual alarm; when the monitoring data exceeds the threshold, it emits a loud sound and flashing lights to remind relevant personnel to take timely measures.

[0059] The implementation principle of this embodiment is as follows: multiple scanners are used for monitoring, and synchronous scanning is achieved through a data processing unit, enabling the acquisition of three-dimensional information of slope 4 from multiple angles, thus improving the comprehensiveness and accuracy of monitoring. Furthermore, the quality of the monitoring data is further optimized by synthesizing the final coordinates of the same monitoring target 2 through weighted averaging. Simultaneously, by generating displacement field cloud maps and setting displacement and rate thresholds for early warning, abnormal deformation of slope 4 can be detected in a timely manner, providing a more reliable guarantee for the prevention of geological disasters.

[0060] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for real-time monitoring of three-dimensional deformation of slopes based on multi-laser scanning, characterized in that: Including the following step: S1: Deploy the monitoring system and set up a set of reference targets outside the slope. The set of reference targets consists of four non-coplanar reference targets, namely the first reference target, the second reference target, the third reference target, and the fourth reference target. Avoid setting up multiple monitoring targets on the slope and install the scanner at a position that can observe all reference targets at the same time. S2: Initial scanning and coordinate recording. After the scanner is first set up, an initial coordinate system is established using the positions of the scanner and the reference target. The scanner simultaneously scans the reference target group and the monitoring target to obtain the initial position coordinates of the reference target group and the monitoring target. S3: Establish a reference coordinate system. Calculate the initial coordinates of the center of the sphere composed of the reference target group using the initial position coordinates of the reference target group, and use the initial coordinates of the center of the sphere as the reference point to establish the reference coordinate system. S4: Real-time scanning and deviation correction. The scanner synchronously scans the reference target group and the monitoring target at set time intervals. The first reference target is the reference target that generates the largest displacement. The registration algorithm is used to correct the first reference target to obtain the coordinates of the first reference target after correction. Then, the current position deviation of the scanner is calculated. The current position deviation of the scanner is used to correct the detection target data in the reference coordinate system. S5: Data analysis and early warning, using the data processing unit to generate a cloud map of the absolute displacement field of the slope; setting thresholds for slope displacement and rate, triggering an alarm when the limits are exceeded; The registration algorithm described in step S4 uses the trilateration formula to first find the original coordinates of the reference point. Then, taking the original coordinates of the reference point as the origin and the distance from the initial position coordinates of the first reference target to the reference point as the radius, a sphere is obtained. The intersection of the line connecting the coordinates of the first reference target and the coordinates of the origin of the reference point with the sphere after calculating the displacement is obtained as the corrected coordinates of the first reference target.

2. The monitoring method according to claim 1, characterized in that: The initial coordinate system takes the location of the scanner as the origin, the horizontal projection direction of the line connecting the scanner and any reference target is the X-axis, and the positive direction of the X-axis is defined as the direction pointing to the first scanner; the opposite direction of the local gravitational acceleration is the Z-axis; the positive direction of the Y-axis strictly follows the right-hand rule.

3. The monitoring method according to claim 1, characterized in that: The Z-axis of the reference coordinate system is a vertical line passing through the reference point, and the positive direction of the Z-axis is the opposite direction of the local gravitational acceleration; the X-axis is a horizontal straight line passing through the reference point, and the direction of the X-axis pointing to the first scanner is the positive direction; the Y-axis passes through the reference point and is orthogonal to both the X-axis and the Z-axis, and the positive direction of the Y-axis strictly follows the right-hand rule.

4. The monitoring method according to claim 1, characterized in that: When only the first reference target is displaced, the registered algorithm is used to calculate the corrected coordinates of the first reference target using the following formula: Calculate the sphere containing the corrected first reference target A2: In the formula: P0 is the initial coordinates of the reference point (PX, PY, PZ); A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA is the distance from P0 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target; Following the principle of minimizing adjustments, the coordinates of the first reference target A2 after correction are clearly defined: In the formula: P0 is the initial coordinate of the reference point (PX, PY, PZ); A1 is the coordinate of the first reference target after displacement (A1X, A1Y, A1Z); A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA is the distance from P0 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target.

5. The monitoring method according to claim 1, characterized in that: When all the reference target groups have generated displacement, the coordinates of the first reference target after correction are calculated using the registration algorithm described above, according to the following formula: The original coordinates of the benchmark points are verified using the trilateration formula, as follows: In the formula: P1 is the coordinate of the reference point (PX1, PY1, PZ1) after the displacement is generated; B1 is the initial coordinate (BX1, BY1, BZ1) of the second reference target; C1 is the initial coordinate of the third benchmark target (CX1, CY1, CZ1). D1 is the initial coordinate (DX1, DY1, DZ1) of the fourth reference target; dB1 is the distance from P1 to B1 after the displacement is generated; dC1 is the distance from P1 to C1 after the displacement occurs; dD1 is the distance from P1 to D1 after the displacement occurs; At this point, the original coordinates P0 of the reference point have two solutions. The correct solution is the one that is closer to the origin of the first reference coordinate system 01. Calculate the sphere containing the corrected first reference target A2: In the formula: P1 is the coordinate of the reference point (PX1, PY1, PZ1) after the displacement is generated; A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA1 is the distance from P1 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target; Using the principle of minimizing adjustments, the coordinates of the first reference target A2 after correction are determined: In the formula: P1 represents the coordinates of the reference point (PX1, PY1, PZ1) after the displacement is generated. A1 is the coordinate of the first reference target after displacement (A1X, A1Y, A1Z); A2 represents the coordinates (A2X, A2Y, A2Z) of the corrected first reference target. dA1 is the distance from P1 to A0, and A0 is the initial coordinates (AX, AY, AZ) of the first reference target.

6. The monitoring method according to claim 1, characterized in that: The scanner described in step S3 uses multiple scanners to scan the slope simultaneously from different angles, and a data processing unit is used to achieve time synchronization. Finally, the weighted average is used to synthesize the final coordinates of the monitoring target.

7. The monitoring method according to claim 6, characterized in that: The data from the scanner is processed by the data processing unit to generate a three-dimensional displacement vector of the monitoring target, and an absolute displacement field cloud map of the slope is constructed based on the vector. The data processing unit presets displacement and velocity thresholds. When the displacement or velocity of the monitoring target in the displacement field cloud map exceeds the threshold, the early warning signal output module is triggered to issue an alarm.

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