Cable obstacle height difference measurement method based on laser rangefinder

Abstract

The invention discloses a cable obstacle height difference measurement method based on a laser rangefinder, relates to the field of tree obstacle measurement, and solves the problem that the existing cable obstacle height difference measurement method consumes a lot of equipment cost and has high maintenance cost. The method comprises the following steps: obtaining an initial image corresponding to a target cable according to a preset angle, and analyzing to obtain an initial tree crown spacing between a tree crown top and a data acquisition terminal; obtaining the tree crown spacing and cable spacing of the target cable under different detection postures; constructing a spatial three-dimensional coordinate system for the target cable, and analyzing the tree obstacle distance of the target cable; generating an abnormal signal, a warning signal or a normal signal corresponding to the target cable according to the tree obstacle distance of the target cable. The invention can reduce the measurement cost of the cable-tree obstacle height difference and realize all-round measurement of the cable-tree obstacle height difference. At the same time, the invention also considers the influence of the tree crown tops on both sides of the cable line on the cable line when the cable line swings.

Description

Technical Field

[0001] The invention relates to the technical field of tree obstacle measurement, in particular to a cable obstacle height difference measurement method based on a laser rangefinder. Background Art

[0002] High-voltage transmission line corridors are mostly located in wild mountainous forest areas. There are a large number of trees growing below or near the transmission line corridors. The rapid growth of trees on both sides of the transmission line and below the line will bring safety hazards to the operation of the transmission line. Therefore, the transmission operation and maintenance department needs to cut down the trees at the corresponding positions to ensure the safe and stable operation of the transmission line. Therefore, it is necessary to measure the height difference of cable obstacles.

[0003] In the prior art, the traditional cable obstacle height difference measurement method usually deploys multiple sensors, then constructs a spatial coordinate system, and then combines the multi-sensor results to calculate the distance between the cable and the top of the tree canopy. The current measurement method consumes a lot of equipment costs, and once a sensor fails, due to the large number of deployed sensor devices, it is necessary to check and confirm the faulty sensor device one by one, which also wastes a lot of manpower and material resources. At the same time, the current cable obstacle height difference measurement method is usually used to analyze the distance between the top of the tree canopy and the cable line in the vertical direction, and does not consider the influence of the top of the tree canopy on both sides of the cable line on the cable line when the cable line swings;

[0004] To this end, the present application proposes a cable obstacle height difference measurement method based on a laser rangefinder. Summary of the invention

[0005] The purpose of the present invention is to propose a cable obstacle height difference measurement method based on a laser rangefinder to solve the problems raised in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A cable obstacle height difference measurement method based on a laser rangefinder, the method comprising the following steps:

[0008] Step S1, obtaining an initial image corresponding to the target cable according to a preset angle, and analyzing to obtain an initial tree crown distance between the top of the tree crown and the data acquisition terminal;

[0009] Step S2, obtaining the tree crown spacing and cable spacing of the target cable under different detection postures;

[0010] Step S3, constructing a spatial three-dimensional coordinate system for the target cable and analyzing the tree obstacle distance of the target cable;

[0011] Step S4, generating an abnormal signal, a warning signal or a normal signal corresponding to the target cable according to the tree obstacle distance of the target cable.

[0012] Furthermore, the step S1 includes the following sub-steps:

[0013] Step S11, the data acquisition terminal acquires an initial image corresponding to the target cable, and simultaneously acquires initial posture information corresponding to the data acquisition terminal; wherein the initial posture information is an initial height and an initial shooting angle corresponding to the data acquisition terminal, and the initial shooting angle is a line-plane angle between a collection direction corresponding to the data acquisition terminal and a horizontal plane where the data acquisition terminal is located;

[0014] Step S12, identifying the tree crown in the initial image corresponding to the target cable;

[0015] Step S13, measuring the initial tree crown distance SGJc between the tree crown top and the data collection terminal.

[0016] Furthermore, the step S12 includes the following sub-steps:

[0017] Step S121, obtaining RGB values ​​corresponding to all pixels in the initial image, and comparing the RGB values ​​of all pixels in the initial image with the RGB tree crown interval;

[0018] Step S122, performing weighted average calculation on the RGB values ​​(Rn, Gn, Bn) corresponding to the pixels in the initial image, converting the RGB values ​​of the pixels in the initial image into grayscale values ​​HDn, and then obtaining a grayscale image corresponding to the initial image;

[0019] Step S123, identifying corresponding edge lines in the grayscale image;

[0020] Step S124, comparing the edge lines in the grayscale image with a preset tree crown outline set;

[0021] If the edge lines in the grayscale image fail to match the crown contour set, the initial image corresponding to the target cable is reselected;

[0022] If the edge line in the grayscale image successfully matches the crown contour set, the corresponding edge line is recorded as the crown edge;

[0023] Step S125, comparing the initial RGB values ​​of all pixels inside the crown edge with the crown RGB interval; recording the pixels whose initial RGB values ​​are in the crown RGB interval as crown pixels, and counting the proportion of the number of crown pixels to all pixels inside the crown edge;

[0024] Step S126, if the tree crown ratio is less than the preset ratio, it is determined that there is no tree crown in the initial image corresponding to the target cable, and the subsequent steps are not performed;

[0025] If the crown ratio is greater than or equal to the preset ratio, it is determined that there is a crown inside the initial image, the crown edge is the position corresponding to the crown in the initial image, and the subsequent steps are entered.

[0026] Further, the detection posture includes a first detection posture and a second detection posture.

[0027] Furthermore, the step S2 includes the following sub-steps:

[0028] Step S21, obtaining the initial posture information corresponding to the data acquisition terminal, and obtaining the initial shooting angle PYJ and initial height CSG of the data acquisition terminal;

[0029] Step S22, obtaining the tree crown top height SGD by the formula SGD=CSG+SGJc×sinPYJ;

[0030] Step S23, setting the data acquisition terminal according to the height of the tree crown top, and acquiring the first tree crown spacing and the first cable spacing corresponding to the target cable in a first detection posture;

[0031] Step S24, obtaining a second tree crown spacing and a second cable spacing corresponding to the target cable in a second detection posture.

[0032] Furthermore, the first detection posture is that the data acquisition terminal is located at the same height corresponding to the top of the tree canopy, that is, the height of the data acquisition terminal is the same as the height of the top of the tree canopy, and the second detection posture is that the data acquisition terminal is located at the same height corresponding to the lowest point of the target cable, that is, the height of the data acquisition terminal is the same as the height of the lowest point of the target cable.

[0033] Furthermore, the step S3 includes the following sub-steps:

[0034] Step S31, establishing a spatial three-dimensional coordinate system with the straight line where the data acquisition terminal is located as the Z axis, the direction along the target cable as the X axis, and the Y axis perpendicular to the ZOX plane as the Y axis;

[0035] Step S32, the position of the data acquisition terminal corresponding to the first detection posture is recorded as P, a vertical line is drawn from the top of the tree crown E to the plane ZOX, the foot of the vertical line is N, and then a vertical line is drawn from N to the target cable, the foot of the vertical line is F, and F is recorded as the cable observation point;

[0036] Step S33, connecting PE, EF and FP to obtain the first observation triangle PEF; wherein PE is the first tree crown distance SGJy;

[0037] Since the horizontal coordinates of point E and point F are equal, EF is perpendicular to plane ZOX, and it can be known that EF is perpendicular to FP, that is, triangle PEF is a right triangle, and the tree barrier deflection angle α is the line-plane angle between straight line EP and plane ZOX, that is, the first deflection angle corresponding to the first detection posture;

[0038] Step S34: The first tree obstacle distance SZJy corresponding to the first detection posture is calculated by the formula SZJy=SGJy×sinα.

[0039] Furthermore, the step S3 also includes the following sub-steps:

[0040] Step S35, record the data acquisition terminal at the position corresponding to the second detection posture as Q, record the lowest point of the target cable as K, record the top of the tree crown as J, connect QJ, JK and KQ to obtain the second observation triangle QJK; wherein QJ is the second tree crown spacing GJe, KQ is the second cable spacing DLJe,

[0041] It can be seen that the tree obstacle deflection angle β is the line-plane angle between the straight line JQ and the plane ZOX, that is, the second deflection angle corresponding to the second detection posture;

[0042] Step S36, by formula Calculate and obtain the second tree obstacle distance SZJe corresponding to the second detection posture;

[0043] Step S37, if the first cable spacing does not exist, the first tree barrier distance corresponding to the first detection posture and the second tree barrier distance corresponding to the second detection posture are compared, and the minimum value is selected as the tree barrier distance corresponding to the target cable;

[0044] Step S38: If there is a first cable spacing, the first tree barrier distance and the third tree barrier distance corresponding to the first detection posture and the second tree barrier distance corresponding to the second detection posture are compared, and the minimum value is selected as the tree barrier distance corresponding to the target cable.

[0045] Furthermore, the calculation process of the third tree barrier distance is:

[0046] The method of determining the cable observation point F is changed to: draw a vertical line of the X axis through point H, intersecting the target cable at point G, and set point G as the cable observation point;

[0047] Connect GH, HI and IG to obtain the third observation triangle GHI; where HI is the third cable spacing DLJy, HG is the third tree crown spacing SGJy, and γ is the angle between the direction of the detection terminal corresponding to the first detection posture and the plane ZOX, that is, the third deflection angle corresponding to the first detection posture;

[0048] By formula The third tree obstacle distance SZJt corresponding to the first detection posture in special circumstances is calculated.

[0049] Furthermore, the step S4 includes the following sub-steps:

[0050] Step S41, obtaining the tree barrier distance corresponding to the target cable, and generating an abnormal signal if the tree barrier distance is located in the first tree barrier interval;

[0051] Step S42, if the tree obstacle distance is within the second tree obstacle interval, generating a warning signal;

[0052] Step S43: if the tree barrier distance is within the third tree barrier interval, a normal signal is generated; wherein the right endpoint of the first tree barrier interval is smaller than the left endpoint of the second tree barrier interval, and the right endpoint of the second tree barrier interval is smaller than the left endpoint of the third tree barrier interval.

[0053] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0054] The present invention obtains an initial image corresponding to the target cable according to a preset angle, analyzes and obtains the initial crown spacing between the crown top and the data acquisition terminal, and then obtains the crown spacing and cable spacing of the target cable under different detection postures, and then constructs a spatial three-dimensional coordinate system for the target cable, and analyzes the tree obstacle distance of the target cable, and generates an abnormal signal, a warning signal or a normal signal corresponding to the target cable according to the tree obstacle distance of the target cable. While reducing the cost of measuring the height difference between the cable and the tree obstacle, the present invention can also realize all-round measurement of the height difference between the cable and the tree obstacle. At the same time, the present invention also considers the influence of the crown tops on both sides of the cable line on the cable line when the cable line swings. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0056] Figure 1 The figure is a flowchart of the method of the present invention.

[0057] Figure 2 This is the initial setting diagram corresponding to the data acquisition terminal in the present invention.

[0058] Figure 3 Schematic diagram of tree obstacle distance calculation corresponding to the first detection posture in the present invention.

[0059] Figure 4 Schematic diagram of tree obstacle distance calculation corresponding to the second detection posture in the present invention.

[0060] Figure 5 It is a schematic diagram of calculating the tree obstacle distance corresponding to a special situation of the first detection posture in the present invention.

[0061] Figure 6 It is a schematic diagram of the structure of the electronic device in the present invention. DETAILED DESCRIPTION

[0062] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0063] Example 1: Please refer to Figure 1-Figure 5 As shown, the technical solution provided by the present invention is: a method for measuring the height difference of a cable obstacle based on a laser rangefinder, and the method is specifically as follows:

[0064] Step S1, obtaining an initial image corresponding to the target cable according to a preset angle, and analyzing to obtain an initial tree crown distance between the top of the tree crown and the data acquisition terminal;

[0065] In this embodiment, step S1 includes the following sub-steps:

[0066] Step S11, the data acquisition terminal acquires an initial image corresponding to the target cable, and simultaneously acquires initial posture information corresponding to the data acquisition terminal;

[0067] The initial posture information specifically refers to the initial height and initial shooting angle corresponding to the data acquisition terminal. In practice, the data acquisition terminal may be a monitoring camera and an infrared rangefinder. In specific implementation, the data acquisition terminal is set up on a power tower. By adjusting the setting height and shooting angle corresponding to the data acquisition terminal, images of the target cable at different viewing angles can be collected.

[0068] Step S12, identifying the tree crown in the initial image corresponding to the target cable;

[0069] Step S121, obtaining RGB values ​​corresponding to all pixels in the initial image, and comparing the RGB values ​​of all pixels in the initial image with the RGB tree crown interval;

[0070] Step S122, performing weighted average calculation on the RGB values ​​(Rn, Gn, Bn) corresponding to the pixels in the initial image, converting the RGB values ​​of the pixels in the initial image into grayscale values ​​HDn, and then obtaining a grayscale image corresponding to the initial image;

[0071] The gray value calculation formula is as follows:

[0072] HDn=A1×Rn+A2×Gn+A3×Bn, where n is the number of the pixel point, Rn represents the R value component corresponding to the pixel point n, Gn represents the G value component corresponding to the pixel point n, and Bn represents the B value component corresponding to the pixel point n; A1, A2 and A3 are weight coefficients, and A1<A3<A2, exemplarily A1=0.114, A2=0.578, A3=0.299;

[0073] Step S123, identifying corresponding edge lines in the grayscale image by edge detection technology;

[0074] Among them, the core codes related to edge detection are as follows:

[0075] import cv2

[0076] import numpy as np

[0077] from matplotlib import pyplot as plt

[0078] img=cv2.imread("Images / 1-1.jpg", 0)

[0079] #Sobel: x, y direction

[0080] x=cv2.Sobel(img,cv2.CV_16S,1,0)

[0081] y=cv2.Sobel(img,cv2.CV_16S,0,1)

[0082] #Data conversion

[0083] Scale_absx=cv2.convertScaleAbs(x)

[0084] Scale_absy=cv2.convertScaleAbs(y)

[0085] result=cv2.addWeighted(Scale_absx, 0.5, Scale_absy, 0.5, 0)

[0086] plt.figure(figsize=(10,8),dpi=100)

[0087] plt.subplot(121), plt.imshow(img, cmap=plt.cm.gray), plt.title('yuantu')

[0088] plt.xticks([]), plt.yticks([])

[0089] plt.subplot(122), plt.imshow(result, cmap=plt.cm.gray), plt.title('Sobel')

[0090] plt.xticks([]), plt.yticks([])

[0091] plt.show()

[0092] Step S124, comparing the edge lines in the grayscale image with the preset crown contour set. If the edge lines in the grayscale image fail to match the crown contour set, reselecting the initial image corresponding to the target cable. If the edge lines in the grayscale image successfully match the crown contour set, recording the corresponding edge lines as crown edges.

[0093] Step S125, comparing the initial RGB values ​​of all pixels inside the crown edge with the crown RGB interval; recording the pixels whose initial RGB values ​​are in the crown RGB interval as crown pixels, and counting the proportion of the number of crown pixels to all pixels inside the crown edge;

[0094] Step S126, if the tree crown ratio is less than the preset ratio, it is determined that there is no tree crown in the initial image corresponding to the target cable, and the subsequent steps are not performed;

[0095] If the crown ratio is greater than or equal to the preset ratio, it is determined that there is a crown inside the initial image, and the crown edge is the position corresponding to the crown in the initial image, and the subsequent steps are entered; wherein the crown RGB interval is specifically the RGB value interval of the color corresponding to the crown;

[0096] Step S13, measuring the initial tree crown distance SGJc between the tree crown top and the data collection terminal by using a laser rangefinder.

[0097] Step S2, obtaining the tree crown spacing and cable spacing of the target cable under different detection postures;

[0098] Wherein, the detection posture includes a first detection posture and a second detection posture;

[0099] In this embodiment, step S2 includes the following sub-steps:

[0100] Step S21, as Figure 2 As shown, the initial posture information corresponding to the data acquisition terminal is obtained, and the initial shooting angle PYJ and the initial height CSG of the data acquisition terminal are obtained; wherein the initial shooting angle is specifically the line-surface angle between the acquisition direction corresponding to the data acquisition terminal and the horizontal plane where the data acquisition terminal is located;

[0101] Step S22, obtaining the tree crown top height SGD by the formula SGD=CSG+SGJc×sinPYJ;

[0102] Step S23, resetting the data acquisition terminal according to the height of the tree crown top, and acquiring the first tree crown spacing and the first cable spacing corresponding to the target cable in the first detection posture;

[0103] Step S24, obtaining a second tree crown spacing and a second cable spacing corresponding to the target cable in a second detection posture; wherein the process of obtaining the second tree crown spacing is the same as the process of obtaining the first tree crown spacing, and the process of obtaining the second cable spacing is the same as the process of obtaining the first cable spacing;

[0104] Specifically, the first detection posture is that the data acquisition terminal is located at the same height corresponding to the top of the tree canopy, that is, the height of the data acquisition terminal is the same as the height of the top of the tree canopy, and the second detection posture is that the data acquisition terminal is located at the same height corresponding to the lowest point of the target cable, that is, the height of the data acquisition terminal is the same as the height of the lowest point of the target cable, and the height of the lowest point of the target cable can be obtained by continuous measurement along the direction of the cable line by a continuous laser rangefinder; the first detection posture corresponds to the first tree canopy spacing and the first cable spacing, and the second detection posture corresponds to the second tree canopy spacing and the second cable spacing;

[0105] Among them, the cable spacing is the spacing obtained by emitting laser from the data acquisition terminal toward the front, that is, along the direction of the target cable; the crown spacing is the spacing obtained by emitting laser from the data acquisition terminal toward the top of the crown and measuring, and the crown spacing may not exist.

[0106] Step S3, constructing a spatial three-dimensional coordinate system for the target cable and analyzing the tree obstacle distance of the target cable;

[0107] The step S3 includes the following sub-steps:

[0108] Step S31, establishing a spatial three-dimensional coordinate system with the straight line where the data acquisition terminal is located as the Z axis, the direction along the target cable as the X axis, and the Y axis perpendicular to the ZOX plane as the Y axis;

[0109] Step S32, as Figure 3 As shown, the position of the data acquisition terminal corresponding to the first detection posture is recorded as P, and a vertical line is drawn from the top of the tree crown E to the plane ZOX, and the foot of the vertical line is N, and then a vertical line is drawn from N to the target cable, and the foot of the vertical line is F, and F is recorded as the cable observation point;

[0110] Step S33, connecting PE, EF and FP to obtain the first observation triangle PEF; wherein PE is the first tree crown distance SGJy;

[0111] Since the horizontal coordinates of point E and point F are equal, EF is perpendicular to plane ZOX, and it can be known that EF is perpendicular to FP, that is, triangle PEF is a right triangle; through the theorem of three perpendicular lines, it can be known that the tree barrier deflection angle α is the line-plane angle between the straight line EP and the plane ZOX, that is, the first deflection angle corresponding to the first detection posture;

[0112] Step S34, the first tree obstacle distance SZJy corresponding to the first detection posture is calculated by a formula, and the formula is as follows:

[0113] SZJy=SGJy×sinα;

[0114] Step S35, as Figure 4 As shown, the data acquisition terminal is recorded as Q at the position corresponding to the second detection posture, the lowest point of the target cable is recorded as K, the top of the tree crown is recorded as J, and QJ, JK and KQ are connected to obtain the second observation triangle QJK; wherein, QJ is the second tree crown spacing GJe, KQ is the second cable spacing DLJe, and the three perpendicular line theorem shows that the tree barrier deflection angle β is the line-surface angle between the straight line JQ and the plane ZOX, that is, the second deflection angle corresponding to the second detection posture;

[0115] Step S36, the second tree obstacle distance SZJe corresponding to the second detection posture is calculated by a formula, and the specific formula is:

[0116]

[0117] Step S37, if the first cable spacing does not exist, the first tree barrier distance corresponding to the first detection posture and the second tree barrier distance corresponding to the second detection posture are compared, and the minimum value is selected as the tree barrier distance corresponding to the target cable;

[0118] Step S38, Figure 5 As shown, if there is a first cable spacing, then as a special case of the first observation triangle, the method of determining the cable observation point F is changed to: draw a perpendicular line of the X axis through point H, intersecting the target cable at point G, and record point G as the cable observation point;

[0119] Connect GH, HI and IG to obtain the third observation triangle GHI; at this time, HI is the third cable spacing DLJy, HG is the third tree crown spacing SGJy, and γ is the angle between the direction of the detection terminal corresponding to the first detection posture and the plane ZOX, that is, the third deflection angle corresponding to the first detection posture;

[0120] The third tree obstacle distance SZJt corresponding to the first detection posture in special cases is calculated by the formula;

[0121] The formula is as follows:

[0122] The first tree barrier distance and the third tree barrier distance corresponding to the first detection posture and the second tree barrier distance corresponding to the second detection posture are compared, and the minimum value is selected as the tree barrier distance corresponding to the target cable.

[0123] Step S4, generating an abnormal signal, a warning signal or a normal signal corresponding to the target cable according to the tree barrier distance of the target cable;

[0124] Step S41, obtaining the tree barrier distance corresponding to the target cable, and generating an abnormal signal if the tree barrier distance is located in the first tree barrier interval;

[0125] Step S42, if the tree obstacle distance is within the second tree obstacle interval, generating a warning signal;

[0126] Step S43: if the tree barrier distance is within the third tree barrier interval, a normal signal is generated; wherein the right endpoint of the first tree barrier interval is smaller than the left endpoint of the second tree barrier interval, and the right endpoint of the second tree barrier interval is smaller than the left endpoint of the third tree barrier interval.

[0127] In practice, normal signals, abnormal signals or warning signals can be sent to the user terminal, and the user responds to the degree of tree obstacle hazard corresponding to the target cable according to different signals. If a normal signal is received, no operation is performed. If an abnormal signal is received, the user immediately goes to the corresponding position of the target cable for inspection. If a warning signal is received, the target cable is continuously monitored.

[0128] In this application, if corresponding calculation formulas appear, the above calculation formulas are all dimensionless and take their numerical calculations. The weight coefficients, proportional coefficients and other coefficients in the formulas are set to a result value obtained by quantifying each parameter. The size of the weight coefficient and the proportional coefficient can be determined as long as it does not affect the proportional relationship between the parameter and the result value.

[0129] Embodiment 2: Figure 6 The present invention is a structural diagram of an electronic device, which may include: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus. The processor may call the logic instructions in the memory to execute a cable obstacle height difference measurement method based on a laser rangefinder, the method comprising: obtaining an initial image corresponding to a target cable according to a preset angle, and analyzing and obtaining an initial tree crown spacing between the top of the tree crown and a data acquisition terminal; obtaining the tree crown spacing and cable spacing of the target cable under different detection postures; constructing a spatial three-dimensional coordinate system for the target cable, and analyzing the tree obstacle distance of the target cable; analyzing the tree obstacle distance of the target cable, and generating an abnormal signal, a warning signal, or a normal signal corresponding to the target cable.

[0130] In addition, the logic instructions in the above-mentioned memory can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art, and the computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0131] Embodiment 3: The present application also provides a computer program product, which includes a computer program stored on a computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the cable obstacle height difference measurement method based on a laser rangefinder provided by the above methods, and the method includes: obtaining an initial image corresponding to the target cable according to a preset angle, and analyzing to obtain an initial crown spacing between the top of the crown and the data acquisition terminal; obtaining the crown spacing and cable spacing of the target cable under different detection postures; constructing a spatial three-dimensional coordinate system for the target cable, and analyzing the tree obstacle distance of the target cable; analyzing the tree obstacle distance of the target cable, and generating an abnormal signal, a warning signal or a normal signal corresponding to the target cable.

[0132] Embodiment 4: The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the above-mentioned cable obstacle height difference measurement method based on a laser rangefinder, the method comprising: obtaining an initial image corresponding to the target cable according to a preset angle, and analyzing to obtain an initial tree crown spacing between the top of the tree crown and the data acquisition terminal; obtaining the tree crown spacing and cable spacing of the target cable under different detection postures; constructing a spatial three-dimensional coordinate system for the target cable, and analyzing the tree obstacle distance of the target cable; analyzing the tree obstacle distance of the target cable, and generating an abnormal signal, a warning signal or a normal signal corresponding to the target cable.

[0133] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0134] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A cable obstacle height difference measurement method based on a laser rangefinder, characterized in that: The method comprises the following steps: Step S1, obtaining an initial image corresponding to the target cable according to a preset angle, and analyzing to obtain an initial tree crown distance between the top of the tree crown and the data acquisition terminal; Step S2, obtaining the tree crown spacing and cable spacing of the target cable in different detection postures; the detection posture includes a first detection posture and a second detection posture; Wherein, the step S2 includes the following sub-steps: Step S21, obtaining the initial posture information corresponding to the data acquisition terminal, and obtaining the initial shooting angle PYJ and initial height CSG of the data acquisition terminal; Step S22, the crown top height SGD is obtained by the formula SGD=CSG+SGJc×sinPYJ; wherein SGJc is the initial crown spacing; Step S23, setting the data acquisition terminal according to the height of the tree crown top, and acquiring the first tree crown spacing and the first cable spacing corresponding to the target cable in a first detection posture; Step S24, obtaining a second tree crown spacing and a second cable spacing corresponding to the target cable in a second detection posture; Step S3, constructing a spatial three-dimensional coordinate system for the target cable and analyzing the tree obstacle distance of the target cable; Wherein, the step S3 includes the following sub-steps: Step S31, establishing a spatial three-dimensional coordinate system with the straight line where the data acquisition terminal is located as the Z axis, the direction along the target cable as the X axis, and the Y axis perpendicular to the ZOX plane as the Y axis; Step S32, the position of the data acquisition terminal corresponding to the first detection posture is recorded as P, a vertical line is drawn from the top of the tree crown E to the plane ZOX, the foot of the vertical line is N, and then a vertical line is drawn from N to the target cable, the foot of the vertical line is F, and F is recorded as the cable observation point; Step S33, connecting PE, EF and FP to obtain a first observation triangle PEF; wherein PE is the first tree crown distance SGJy; Since the horizontal coordinates of point E and point F are equal, EF is perpendicular to plane ZOX, and it can be known that EF is perpendicular to FP, that is, triangle PEF is a right triangle, and the tree barrier deflection angle α is the line-plane angle between straight line EP and plane ZOX, that is, the first deflection angle corresponding to the first detection posture; Step S34, calculating the first tree obstacle distance SZJy corresponding to the first detection posture by the formula SZJy=SGJy×sinα; Step S35, record the position of the data acquisition terminal at the second detection posture as Q, record the lowest point of the target cable as K, record the top of the tree crown as J, connect QJ, JK and KQ to obtain the second observation triangle QJK; wherein QJ is the second tree crown spacing GJe, and KQ is the second cable spacing DLJe; It can be seen that the tree obstacle deflection angle β is the line-plane angle between the straight line JQ and the plane ZOX, that is, the second deflection angle corresponding to the second detection posture; Step S36, by formula Calculate and obtain the second tree obstacle distance SZJe corresponding to the second detection posture; Step S37, if the first cable spacing does not exist, the first tree barrier distance corresponding to the first detection posture and the second tree barrier distance corresponding to the second detection posture are compared, and the minimum value is selected as the tree barrier distance corresponding to the target cable; Step S38, if there is a first cable spacing, compare the first tree barrier distance and the third tree barrier distance corresponding to the first detection posture, and the second tree barrier distance corresponding to the second detection posture, and select the minimum value as the tree barrier distance corresponding to the target cable; The calculation process of the third tree barrier distance is: The method of determining the cable observation point F is changed to: draw a vertical line of the X axis through point H, intersecting the target cable at point G, and set point G as the cable observation point; Connect GH, HI and IG to obtain the third observation triangle GHI; where HI is the third cable spacing DLJy, HG is the third tree crown spacing SGJy, and γ is the angle between the direction of the detection terminal corresponding to the first detection posture and the plane ZOX, that is, the third deflection angle corresponding to the first detection posture; By formula Calculate and obtain the third tree obstacle distance SZJt corresponding to the first detection posture; Step S4, generating an abnormal signal, a warning signal or a normal signal corresponding to the target cable according to the tree obstacle distance of the target cable.

2. The cable obstacle height difference measurement method based on a laser rangefinder according to claim 1, characterized in that: The step S1 includes the following sub-steps: Step S11, the data acquisition terminal acquires an initial image corresponding to the target cable, and simultaneously acquires initial posture information corresponding to the data acquisition terminal; wherein the initial posture information is an initial height and an initial shooting angle corresponding to the data acquisition terminal, and the initial shooting angle is a line-plane angle between a collection direction corresponding to the data acquisition terminal and a horizontal plane where the data acquisition terminal is located; Step S12, identifying the tree crown in the initial image corresponding to the target cable; Step S13, measuring the initial tree crown distance SGJc between the tree crown top and the data collection terminal.

3. The cable obstacle height difference measurement method based on laser rangefinder according to claim 2 is characterized in that: The step S12 includes the following sub-steps: Step S121, obtaining RGB values ​​corresponding to all pixels in the initial image, and comparing the RGB values ​​of all pixels in the initial image with the RGB tree crown interval; Step S122, performing weighted average calculation on the RGB values ​​(Rn, Gn, Bn) corresponding to the pixels in the initial image, converting the RGB values ​​of the pixels in the initial image into grayscale values ​​HDn, where n is the number of the pixel, and then obtaining a grayscale image corresponding to the initial image; Step S123, identifying corresponding edge lines in the grayscale image; Step S124, comparing the edge lines in the grayscale image with a preset tree crown outline set; If the edge lines in the grayscale image fail to match the crown contour set, the initial image corresponding to the target cable is reselected; If the edge line in the grayscale image successfully matches the crown contour set, the corresponding edge line is recorded as the crown edge; Step S125, comparing the initial RGB values ​​of all pixels inside the crown edge with the crown RGB interval; recording the pixels whose initial RGB values ​​are in the crown RGB interval as crown pixels, and counting the proportion of the number of crown pixels to all pixels inside the crown edge; Step S126, if the tree crown ratio is less than the preset ratio, it is determined that there is no tree crown in the initial image corresponding to the target cable, and the subsequent steps are not performed; If the crown ratio is greater than or equal to the preset ratio, it is determined that there is a crown inside the initial image, the crown edge is the position corresponding to the crown in the initial image, and the subsequent steps are entered.

4. The cable obstacle height difference measurement method based on laser rangefinder according to claim 1, characterized in that: The first detection posture is that the data acquisition terminal is located at the same height corresponding to the top of the tree canopy, that is, the height of the data acquisition terminal is the same as the height of the top of the tree canopy. The second detection posture is that the data acquisition terminal is located at the same height corresponding to the lowest point of the target cable, that is, the height of the data acquisition terminal is the same as the height of the lowest point of the target cable.

5. The cable obstacle height difference measurement method based on laser rangefinder according to claim 1, characterized in that: The step S4 includes the following sub-steps: Step S41, obtaining the tree barrier distance corresponding to the target cable, and generating an abnormal signal if the tree barrier distance is located in the first tree barrier interval; Step S42, if the tree obstacle distance is within the second tree obstacle interval, generating a warning signal; Step S43: if the tree barrier distance is in the third tree barrier interval, a normal signal is generated; wherein the right endpoint of the first tree barrier interval is smaller than the left endpoint of the second tree barrier interval, and the right endpoint of the second tree barrier interval is smaller than the left endpoint of the third tree barrier interval.

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