A method and system for 3D trajectory detection of underground cables using multi-point rotation measurements

Abstract

The application provides a kind of multi-point rotary measurement underground cable three-dimensional trajectory detection method and system, including using ground penetrating radar to carry out multiple rotary detection at different heading angles on the measuring point of detection area;Filter out the measuring point that can detect more than the set number of underground cable, and determine the coordinates of these measuring points in three-dimensional rectangular coordinate system;Calculate the distance between the measuring point and the underground cable at different heading angles;Calculate the actual distribution of the part of underground cable in three-dimensional space;Calculate the actual distribution of the corresponding underground cable of all adjacent measuring points in the filtered measuring points, and connect them with smooth lines to obtain the three-dimensional trajectory of the underground cable in the detection area.The application can calculate the distribution of underground cable in three-dimensional space by using the measurement data of multiple different heading angles of two-dimensional ground penetrating radar, can be applied to the case where the trend of underground cable is unknown, and greatly simplifies the step of planning the measurement path in advance for ground penetrating radar.

Description

Technical Field

[0001] This invention belongs to the field of underground cable detection technology, specifically relating to a method and system for detecting the three-dimensional trajectory of underground cables using multi-point rotation measurement. Background Technology

[0002] In recent years, with the development of smart grids, the application of power cables in various distribution networks has increased significantly, and cable transmission has become the main power transmission route in distribution networks. Because power cables are buried underground year-round, the underground cable network has undergone significant modifications during power grid development, resulting in the loss or outdated of relevant data. This makes it difficult to accurately identify and locate cables during faults and routine maintenance. Furthermore, underground cables are buried in opaque underground spaces with complex structures; failure to accurately locate cables during construction can lead to engineering accidents. Therefore, improving the accuracy of cable detection and location, and reducing construction injuries, is an urgent problem to be solved in engineering construction.

[0003] Metal pipe detectors are currently the most widely used devices for detecting underground cable routes. They determine the specific location of cables by detecting changes in the strength of ground electromagnetic signals, offering high accuracy. However, pipe detectors can only detect metal pipes and require a pulse signal with sufficient energy to be injected while the pipe is offline, thus limiting their application. With the development of geological exploration technology, ground-penetrating radar (GPR) technology, which utilizes the differences in the electromagnetic properties of underground media to detect the underground environment, has developed rapidly. GPR technology extracts target characteristic information by analyzing echo signals, offering advantages such as fast detection speed, continuous process, high resolution, and non-destructive testing. It has been widely used in geological exploration, pipeline inspection, and quality inspection of subsurface structures such as highways, bridges, dams, and airport runways.

[0004] Existing two-dimensional ground-penetrating radars (GPRs) are typically deployed in a linear fashion, using a cart to image data based on distance or time. Post-detection analysis is then performed manually to determine the location of underground pipelines at specific distances or times. For detecting existing underground cables, the method primarily relies on pre-planned, equally spaced GPR measurement paths perpendicular to the cable's direction to pinpoint its location. However, this approach is insufficient for detecting underground cables with unknown routes. Summary of the Invention

[0005] In view of this, the present invention aims to solve the problem that existing methods of using two-dimensional ground penetrating radar to detect underground cable trajectories are insufficient for detecting the direction of unknown underground cables.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a method for detecting the three-dimensional trajectory of underground cables using multi-point rotation measurement, comprising the following steps:

[0008] Ground-penetrating radar is used to detect points in the detection area at different heading angles. The measurement points are several points randomly selected in the detection area.

[0009] The identification status of underground cables at each measurement point is determined based on the waveform diagram of the measurement point, and the number of times underground cables are detected at each measurement point is recorded;

[0010] Filter out measurement points that exceed the set number of times, randomly select two adjacent measurement points from them, and determine the coordinates of these two measurement points in the three-dimensional rectangular coordinate system;

[0011] Construct the linear expressions of the underground cables corresponding to the two selected measurement points in a three-dimensional rectangular coordinate system;

[0012] Based on the waveform diagram of the measurement points, the distance between the two selected measurement points and the underground cable is identified at different heading angles;

[0013] Based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of some underground cables in three-dimensional space is calculated;

[0014] The actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points is calculated and connected with smooth lines to obtain the three-dimensional trajectory of underground cables in the detection area.

[0015] Furthermore, ground-penetrating radar is used to conduct detection at measurement points in the detection area at different heading angles, specifically including:

[0016] Set the rotation angle to α, and rotate the ground penetrating radar at the measurement point at intervals of α, for a total of 180 / α measurements, where 180 / α is an integer.

[0017] Furthermore, the coordinate axes of the three-dimensional rectangular coordinate system are specifically as follows:

[0018] In a three-dimensional Cartesian coordinate system, the x-axis represents true north, the y-axis represents true east, and the z-axis represents the direction of gravity. Furthermore, the linear expression for some underground cables in a three-dimensional Cartesian coordinate system is as follows:

[0019] (x-x0) / m=(y-y0) / n=(z-z0) / p

[0020] Here, (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable.

[0021] Furthermore, based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of some underground cables in three-dimensional space is calculated, specifically using the following formula:

[0022]

[0023] Where (x0, y0, z0) is a point on the straight line, and vector (m, n, p) is a non-zero vector parallel to the underground cable; any two measurement points A(x a y a , z a B(x) b y b , z b The underground cable was detected at measurement point A1(x) three times. A1 ,y A1 ,z A1 ), A2(x A2 ,y A2 ,z A2 ), A3(x A3 ,y A3 ,z A3 B1(x) B1 ,y B1 ,z B1 B2(x) B2 ,y B2 ,z B2 B3(x) B3 ,y B3 ,z B3 The corresponding heading angles are α1, α2, α3, β1, β2, β3, respectively; the distances from points A1, A2, A3 to A are D, respectively. A1 D A2 D A3 The distances of B1, B2, and B3 from B are respectively D B1 D B2 D B3 .

[0024] Secondly, the present invention provides a three-dimensional trajectory detection system for underground cables using multi-point rotation measurement, comprising:

[0025] The data acquisition unit is used to acquire data when the ground penetrating radar detects at measurement points in the detection area at different heading angles. The measurement points are several points randomly selected in the detection area.

[0026] The recording unit is used to determine the identification status of underground cables at each measurement point based on the waveform diagram of the measurement point, and to record the number of times underground cables are detected at each measurement point;

[0027] The filtering unit is used to filter out measurement points that have exceeded a set number of times, and then randomly select two adjacent measurement points to determine the coordinates of these two measurement points in a three-dimensional rectangular coordinate system.

[0028] The line construction unit constructs the linear expression of the underground cable corresponding to the two selected measurement points in a three-dimensional rectangular coordinate system.

[0029] The first calculation unit is used to identify the distance between the two selected measurement points and the underground cable at different heading angles based on the waveform diagram of the measurement points;

[0030] The second calculation unit is used to calculate the actual distribution of some underground cables in three-dimensional space based on the coordinates of the measurement points and the distance between the measurement points and the underground cables.

[0031] The trajectory generation unit is used to obtain the actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points, and connect them with smooth lines to obtain the three-dimensional trajectory of underground cables in the detection area.

[0032] Furthermore, in the data acquisition unit, data is acquired from the ground-penetrating radar at measurement points in the detection area at different heading angles, specifically including:

[0033] Set the rotation angle to α, and rotate the ground penetrating radar at the measurement point at intervals of α, for a total of 180 / α measurements, where 180 / α is an integer.

[0034] Furthermore, in the filtering unit, the coordinate axis directions of the three-dimensional rectangular coordinate system are specifically as follows:

[0035] In a three-dimensional rectangular coordinate system, the x-axis points to due north, the y-axis to due east, and the z-axis to the direction of gravity.

[0036] Furthermore, in the straight-line construction unit, the linear expression of some underground cables in the three-dimensional rectangular coordinate system is as follows:

[0037] (x-x0) / m=(y-y0) / n=(z-z0) / p

[0038] Here, (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable.

[0039] Furthermore, in the second calculation unit, based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of some underground cables in three-dimensional space is calculated, specifically using the following calculation formula:

[0040]

[0041] Where (x0, y0, z0) is a point on the straight line, and vector (m, n, p) is a non-zero vector parallel to the underground cable; any two measurement points A(x a y a , z a B(x)b y b , z b The underground cable was detected at measurement point A1(x) three times. A1 ,y A1 ,z A1 ), A2(x A2 ,y A2 ,z A2 ), A3(x A3 ,y A3 ,z A3 B1(x) B1 ,y B1 ,z B1 B2(x) B2 ,y B2 ,z B2 B3(x) B3 ,y B3 ,z B3 The corresponding heading angles are α1, α2, α3, β1, β2, β3, respectively; the distances from points A1, A2, A3 to A are D, respectively. A1 D A2 D A3 The distances of B1, B2, and B3 from B are respectively D B1 D B2 D B3 .

[0042] In summary, this invention provides a method and system for detecting the three-dimensional trajectory of underground cables using multi-point rotational measurement. The method includes: utilizing ground-penetrating radar (GPR) to perform multiple rotational measurements at different heading angles at measurement points within a detection area; selecting measurement points that can detect underground cables more than a set number of times, and determining the coordinates of these measurement points in a three-dimensional Cartesian coordinate system; identifying the distance between the measurement points and the underground cables at different heading angles based on the measurement point waveform diagram; calculating the actual distribution of the underground cables in three-dimensional space based on the measurement point coordinates and the distances between the measurement points and the underground cables; calculating the actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points, and connecting them with smooth lines to obtain the three-dimensional trajectory of the underground cables in the detection area. This invention, by utilizing measurement data from multiple different heading angles of a two-dimensional GPR, can calculate the distribution of underground cables in three-dimensional space, making it applicable to situations where the underground cable route is unknown, while greatly simplifying the steps required for GPR to pre-plan the measurement path. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 A flowchart illustrating a method for detecting the three-dimensional trajectory of underground cables using multi-point rotation measurement, provided in an embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram illustrating the actual distribution of underground cables provided in an embodiment of the present invention. Detailed Implementation

[0046] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0047] In recent years, with the development of smart grids, the application of power cables in various distribution networks has increased significantly, and cable transmission has become the main power transmission route in distribution networks. Because power cables are buried underground year-round, the underground cable network has undergone significant modifications during power grid development, resulting in the loss or outdated of relevant data. This makes it difficult to accurately identify and locate cables during faults and routine maintenance. Furthermore, underground cables are buried in opaque underground spaces with complex structures; failure to accurately locate cables during construction can lead to engineering accidents. Therefore, improving the accuracy of cable detection and location, and reducing construction injuries, is an urgent problem to be solved in engineering construction.

[0048] Metal pipe detectors are currently the most widely used devices for detecting underground cable routes. They determine the specific location of cables by detecting changes in the strength of ground electromagnetic signals, offering high accuracy. However, pipe detectors can only detect metal pipes and require a pulse signal with sufficient energy to be injected while the pipe is offline, thus limiting their application. With the development of geological exploration technology, ground-penetrating radar (GPR) technology, which utilizes the differences in the electromagnetic properties of underground media to detect the underground environment, has developed rapidly. GPR technology extracts target characteristic information by analyzing echo signals, offering advantages such as fast detection speed, continuous process, high resolution, and non-destructive testing. It has been widely used in geological exploration, pipeline inspection, and quality inspection of subsurface structures such as highways, bridges, dams, and airport runways.

[0049] Existing two-dimensional ground-penetrating radars (GPRs) are typically deployed in a linear fashion, using a cart to image data based on distance or time. Post-detection analysis is then performed manually to determine the location of underground pipelines at specific distances or times. For detecting existing underground cables, the method primarily relies on pre-planned, equally spaced GPR measurement paths perpendicular to the cable's direction to pinpoint its location. However, this approach is insufficient for detecting underground cables with unknown routes.

[0050] Based on this, the present invention provides a method and system for detecting the three-dimensional trajectory of underground cables by multi-point rotation measurement.

[0051] The following is a detailed description of an embodiment of the multi-point rotation measurement method for detecting the three-dimensional trajectory of underground cables according to the present invention.

[0052] Please see Figure 1 This embodiment provides a method for detecting the three-dimensional trajectory of underground cables using multi-point rotation measurement, including the following steps:

[0053] S100: Ground penetrating radar is used to detect at measurement points in the detection area at different heading angles. The measurement points are several points randomly selected in the detection area.

[0054] It should be noted that the ground-penetrating radar used to measure underground cables integrates a nine-axis high-precision gyroscope and a high-precision GPS positioning module, which can read the ground-penetrating radar heading angle and latitude and longitude information in real time.

[0055] During measurement, at each measurement point, the ground-penetrating radar heading angle is measured sequentially at 0°, (0+α)°, (0+2α)°, (0+3α)°…, 180 / α times. α is the rotation angle for each measurement, and 180 / α is a positive integer. The rotation angle α for each measurement can be selected according to actual needs.

[0056] S200: Based on the waveform diagram of the measurement points, determine the identification status of underground cables at each measurement point and record the number of times underground cables are detected at each measurement point.

[0057] Ground penetrating radar transmits high-frequency electromagnetic waves into the ground through a transmitting antenna and receives the reflected electromagnetic waves back to the ground through a receiving antenna. When the electromagnetic waves propagate in the underground medium, they are reflected when they encounter interfaces with electrical differences. Based on the waveform, amplitude, intensity, and time-related changes of the received electromagnetic waves, the spatial location, structure, shape, and burial depth of the underground medium can be inferred.

[0058] S300: Filter out measurement points that have exceeded the set number of times, randomly select two adjacent measurement points from them, and determine the coordinates of these two measurement points in the three-dimensional rectangular coordinate system.

[0059] It should be noted that, among the 180 / α measurements, those measuring points that detected underground cables more than the set number of times (in actual implementation, this was set to 3 times) were selected, and then any two measuring points A(x) were chosen from these. a y a , z a B(x) b y b , z b The corresponding heading angles for the waveforms A1, A2, A3, B1, B2, and B3 of the detected underground cable are α1, α2, α3, β1, β2, and β3. Measurement point A(x) a y a , z a B(x) b y b , z b Let (x, y) be two points in a three-dimensional Cartesian coordinate system with a fixed point on the ground as the origin, north as the x-axis, east as the y-axis, and the direction of gravity as the z-axis. a y a , z a ), (x b y b , z b It is derived from latitude and longitude information obtained by ground penetrating radar.

[0060] S400: Construct the linear expression of the portion of the underground cable corresponding to the two selected measurement points in a three-dimensional rectangular coordinate system.

[0061] Let the underground cable be a straight line in a three-dimensional Cartesian coordinate system, expressed as (x-x0) / m=(y-y0) / n=(z-z0) / p, where (x0,y0,z0) is a point on the line, and the vector (m,n,p) is a non-zero vector parallel to the line. The distribution of the constructed straight line in the three-dimensional Cartesian coordinate system is as follows. Figure 2 As shown.

[0062] S500: Identifies the distance between two selected measurement points and the underground cable at different heading angles based on the waveform diagram of the measurement points.

[0063] It should be noted that the distances DA1, DA2, DA3, DB1, DB2, and DB3 between the cables and the measurement points corresponding to waveforms A1, A2, A3, B1, B2, and B3 are identified. The distances DA1, DA2, and DA3 between the cables and the measurement points are the distances between the straight line and the point A(x) set in step S400. a y a , z a The planes intersect at heading angles α1, α2, and α3, respectively, at points A(x). a y a , za The distance between the line and point B(x) is the distance between the line set in step S400 and the line passing through point B(x). b y b , z b The distances from point B(xb, yb, zb) to the intersection points of the planes at heading angles β1, β2, and β3, respectively. The distances of the two measurement points from the underground cable are as follows: Figure 2 As shown.

[0064] S600: Based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, calculate the actual distribution of some underground cables in three-dimensional space.

[0065] Based on the detection angle and range of the ground penetrating radar, determine the area that measurement points A and B can cover, and extract the corresponding line segment L from the solved expression.

[0066] The three-dimensional distribution of the ground cables corresponding to measurement points A and B is calculated using the following formula:

[0067]

[0068] Where (x0, y0, z0) is a point on the straight line, and vector (m, n, p) is a non-zero vector parallel to the underground cable; any two measurement points A(x a y a , z a B(x) b y b , z b The underground cable was detected at measurement point A1(x) three times. A1 ,y A1 ,z A1 ), A2(x A2 ,y A2 ,z A2 ), A3(x A3 ,y A3 ,z A3 B1(x) B1 ,y B1 ,z B1 B2(x) B2 ,y B2 ,z B2 B3(x) B3 ,y B3 ,z B3 The corresponding heading angles are α1, α2, α3, β1, β2, β3, respectively; the distances from points A1, A2, A3 to A are D, respectively. A1 D A2 D A3 The distances of B1, B2, and B3 from B are respectively D B1D B2 D B3 .

[0069] S700: Calculate the actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points, and connect them with smooth lines to obtain the three-dimensional trajectory of underground cables in the detection area.

[0070] For all measurement points, the aforementioned method is used to calculate and determine the line segments L1, L2, L3, etc., representing the cable.

[0071] In a three-dimensional Cartesian coordinate system, the calculated line segments are connected by a smooth curve to form a complete curve, which represents the three-dimensional trajectory of the underground cable. This three-dimensional trajectory can be constructed in real time and visualized in three dimensions.

[0072] This embodiment provides a method for detecting the three-dimensional trajectory of underground cables using multi-point rotation measurement. The method includes: using ground-penetrating radar (GPR) to perform multiple rotational measurements at different heading angles at measurement points in the detection area; selecting measurement points that can detect underground cables more than a set number of times, and determining the coordinates of these measurement points in a three-dimensional Cartesian coordinate system; identifying the distance between the measurement points and the underground cables at different heading angles based on the waveform diagram of the measurement points; calculating the actual distribution of the underground cables in three-dimensional space based on the coordinates of the measurement points and the distances between the measurement points and the underground cables; calculating the actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points, and connecting them with smooth lines to obtain the three-dimensional trajectory of the underground cables in the detection area. This invention, by utilizing measurement data from multiple different heading angles of a two-dimensional GPR, can calculate the distribution of underground cables in three-dimensional space, making it applicable to situations where the direction of underground cables is unknown, and greatly simplifying the steps required for GPR to pre-plan the measurement path.

[0073] The above is a detailed description of an embodiment of a multi-point rotation measurement method for detecting the three-dimensional trajectory of underground cables according to the present invention. The following will provide a detailed description of an embodiment of a multi-point rotation measurement system for detecting the three-dimensional trajectory of underground cables according to the present invention.

[0074] This embodiment provides a three-dimensional trajectory detection system for underground cables using multi-point rotation measurement, comprising: a data acquisition unit, a recording unit, a filtering unit, a straight line construction unit, a first calculation unit, a second calculation unit, and a trajectory generation unit.

[0075] In this embodiment, the data acquisition unit is used to acquire data when the ground penetrating radar detects at different heading angles at measurement points in the detection area. The measurement points are several points randomly selected in the detection area.

[0076] It should be noted that the data acquisition unit acquires data from ground-penetrating radar measurements taken at different heading angles within the detection area, specifically including:

[0077] Set the rotation angle to α, and rotate the ground penetrating radar at the measurement point at intervals of α, for a total of 180 / α measurements, where 180 / α is an integer.

[0078] In this embodiment, the recording unit is used to determine the underground cable identification status of each measurement point based on the waveform diagram of the measurement point, and to record the number of times the underground cable is detected at each measurement point.

[0079] In this embodiment, the filtering unit is used to filter out measurement points that have exceeded a set number of times, and then arbitrarily select two adjacent measurement points to determine the coordinates of these two measurement points in a three-dimensional rectangular coordinate system.

[0080] It should be noted that, in the filtering unit, the coordinate axes of the three-dimensional rectangular coordinate system are specifically as follows:

[0081] In a three-dimensional rectangular coordinate system, the x-axis points to due north, the y-axis to due east, and the z-axis to the direction of gravity.

[0082] In this embodiment, the straight line construction unit constructs the straight line expression of the underground cable corresponding to the two selected measurement points in a three-dimensional rectangular coordinate system.

[0083] It should be noted that, in the straight-line construction unit, the straight-line expression of some underground cables in the three-dimensional rectangular coordinate system is as follows:

[0084] (x-x0) / m=(y-y0) / n=(z-z0) / p

[0085] Here, (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable.

[0086] In this embodiment, the first calculation unit is used to identify the distance between the two selected measurement points and the underground cable at different heading angles based on the waveform diagram of the measurement points.

[0087] In this embodiment, the second calculation unit is used to calculate the actual distribution of a portion of the underground cable in three-dimensional space based on the coordinates of the measurement point and the distance between the measurement point and the underground cable.

[0088] It should be noted that in the second calculation unit, based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of some underground cables in three-dimensional space is calculated, specifically using the following calculation formula:

[0089]

[0090] Where (x0, y0, z0) is a point on the straight line, and vector (m, n, p) is a non-zero vector parallel to the underground cable; any two measurement points A(x a y a , z a B(x) b y b , z b The underground cable was detected at measurement point A1(x) three times. A1 ,y A1 ,z A1 ), A2(x A2 ,y A2 ,z A2 ), A3(x A3 ,y A3 ,z A3 B1(x) B1 ,y B1 ,z B1 B2(x) B2 ,y B2 ,z B2 B3(x) B3 ,y B3 ,z B3 The corresponding heading angles are α1, α2, α3, β1, β2, β3, respectively; the distances from points A1, A2, A3 to A are D, respectively. A1 D A2 D A3 The distances of B1, B2, and B3 from B are respectively D B1 D B2 D B3 .

[0091] In this embodiment, the trajectory generation unit is used to obtain the actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points, and connect them with smooth lines to obtain the three-dimensional trajectory of underground cables in the detection area.

[0092] It should be noted that the trajectory detection system provided in this embodiment is used to implement the trajectory detection method provided in the foregoing embodiment. The specific settings of each unit are based on the complete implementation of the method, and will not be repeated here.

[0093] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting the three-dimensional trajectory of underground cables using multi-point rotation measurement, characterized in that, Includes the following steps: Ground-penetrating radar is used to detect points in the detection area at different heading angles. The measurement points are several points randomly selected in the detection area. The identification status of underground cables at each measurement point is determined based on the waveform diagram of the measurement point, and the number of times underground cables are detected at each measurement point is recorded; Filter out measurement points that exceed the set number of times, randomly select two adjacent measurement points from them, and determine the coordinates of these two measurement points in the three-dimensional rectangular coordinate system; Construct the linear expressions of the underground cables corresponding to the two selected measurement points in the three-dimensional rectangular coordinate system; Based on the waveform diagram of the measurement points, the distance between the two selected measurement points and the underground cable is identified at different heading angles; Based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of the underground cables in three-dimensional space is calculated. The actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points is calculated, and then connected with smooth lines to obtain the three-dimensional trajectory of underground cables in the detection area. Based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of the underground cables in three-dimensional space is calculated using the following formula: Where (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable; Any two measurement points A(x) a y a , z a B(x) b y b , z b The underground cable was detected at measurement point A1(x) three times. A1 , y A1 , z A1 ), A2(x A2 , y A2 , z A2 ), A3(x A3 , y A3 , z A3 B1(x) B1 , y B1 , z B1 B2(x) B2 , y B2 , z B2 B3(x) B3 , y B3 , z B3 The corresponding heading angles are α1, α2, α3, β1, β2, β3, respectively; the distances from points A1, A2, A3 to A are D, respectively. A1 D A2 D A3 The distances of B1, B2, and B3 from B are respectively D B1 D B2 D B3 .

2. The method for detecting the three-dimensional trajectory of underground cables by multi-point rotation measurement according to claim 1, characterized in that, Ground-penetrating radar is used to detect points in the detection area at different heading angles, specifically including: Set the rotation angle to α, and then place the ground-penetrating radar at the measurement points at intervals of α. Rotation measurements were performed a total of 180 / α times, where 180 / α is an integer.

3. The method for detecting the three-dimensional trajectory of underground cables by multi-point rotation measurement according to claim 1, characterized in that, The coordinate axes of the three-dimensional rectangular coordinate system are specifically as follows: The x-axis of the three-dimensional rectangular coordinate system is due north, the y-axis is due east, and the z-axis is the direction of gravity.

4. The method for detecting the three-dimensional trajectory of underground cables by multi-point rotation measurement according to claim 3, characterized in that, The linear expressions for some underground cables in the three-dimensional rectangular coordinate system are as follows: (x-x0) / m=(y-y0) / n=(z-z0) / p Here, (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable.

5. A three-dimensional trajectory detection system for underground cables using multi-point rotation measurement, characterized in that, include: The data acquisition unit is used to acquire data when the ground penetrating radar detects at measurement points in the detection area at different heading angles, wherein the measurement points are several points randomly selected in the detection area; The recording unit is used to determine the identification status of underground cables at each measurement point based on the waveform diagram of the measurement point, and to record the number of times underground cables are detected at each measurement point; The filtering unit is used to filter out measurement points that have exceeded a set number of times, and then randomly select two adjacent measurement points to determine the coordinates of these two measurement points in a three-dimensional rectangular coordinate system. A straight line construction unit is used to construct the straight line expression of the portion of the underground cable corresponding to the two selected measurement points in the three-dimensional rectangular coordinate system; The first calculation unit is used to identify the distance between the two selected measurement points and the underground cable at different heading angles based on the waveform diagram of the measurement points; The second calculation unit is used to calculate the actual distribution of the underground cable in three-dimensional space based on the coordinates of the measurement point and the distance between the measurement point and the underground cable; The trajectory generation unit is used to obtain the actual distribution of underground cables corresponding to all adjacent measurement points among the selected measurement points, and connect them with smooth lines to obtain the three-dimensional trajectory of underground cables in the detection area. In the second calculation unit, based on the coordinates of the measurement points and the distance between the measurement points and the underground cables, the actual distribution of the underground cables in three-dimensional space is calculated, specifically using the following calculation formula: Where (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable; Any two measurement points A(x) a y a , z a B(x) b y b , z b The underground cable was detected at measurement point A1(x) three times. A1 , y A1 , z A1 ), A2(x A2 , y A2 , z A2 ), A3(x A3 , y A3 , z A3 B1(x) B1 , y B1 , z B1 B2(x) B2 , y B2 , z B2 B3(x) B3 , y B3 , z B3 The corresponding heading angles are α1, α2, α3, β1, β2, β3, respectively; the distances from points A1, A2, A3 to A are D, respectively. A1 D A2 D A3 The distances of B1, B2, and B3 from B are respectively D B1 D B2 D B3 .

6. The underground cable three-dimensional trajectory detection system for multi-point rotation measurement according to claim 5, characterized in that, The data acquisition unit acquires data from ground-penetrating radar measurements taken at different heading angles within the detection area, specifically including: Set the rotation angle to α, and then place the ground-penetrating radar at the measurement points at intervals of α. Rotation measurements were performed a total of 180 / α times, where 180 / α is an integer.

7. The underground cable three-dimensional trajectory detection system for multi-point rotation measurement according to claim 5, characterized in that, In the filtering unit, the coordinate axis directions of the three-dimensional rectangular coordinate system are specifically as follows: The x-axis of the three-dimensional rectangular coordinate system is due north, the y-axis is due east, and the z-axis is the direction of gravity.

8. The underground cable three-dimensional trajectory detection system for multi-point rotation measurement according to claim 7, characterized in that, In the aforementioned straight-line construction unit, the linear expression of a portion of the underground cable in the three-dimensional rectangular coordinate system is as follows: (x-x0) / m=(y-y0) / n=(z-z0) / p Here, (x0,y0,z0) is a point on the line, and vector (m,n,p) is a non-zero vector that is parallel to the underground cable.

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