Method and system for collecting a wire point cloud

Abstract

The application discloses a kind of acquisition method and system of wire point cloud, laser radar is arranged on driving equipment, for adjusting the pitch angle and roll angle of laser radar, to adjust the position change of the measurement area of laser radar;Acquisition method includes: acquisition obtains multiple representative wire points on wire and the representative tangent corresponding to each representative wire point;According to representative wire point and representative tangent, adjust the pitch angle and roll angle of laser radar, so that laser radar is sequentially through each representative wire point according to the way that measurement area and corresponding representative tangent are parallel to each other, to measure the wire point of each different position on wire, obtain the position data of each wire point on wire.In the present application, the adjustment change of the pitch angle and roll angle of laser radar can be realized, so that the measurement area of laser radar can be parallel to representative tangent, realize more wire point measurement at a time, improve scanning efficiency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of power grid maintenance technology, and in particular to a method for acquiring conductor point clouds and a system for acquiring conductor point clouds. Background Technology

[0002] Conductors in power transmission lines are one of the important circuit components that maintain the operation of the power grid and ensure the normal transmission of electrical energy. Accurate and effective monitoring of the conductor's posture is of great significance in the daily maintenance of the power grid.

[0003] Scanning various points on a guideline using lidar to obtain its position and orientation in space is an effective way to monitor its state. However, current methods for monitoring guidelines also suffer from low efficiency in scanning point clouds on the guideline. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for acquiring point clouds on a guideline, which can improve the efficiency and accuracy of point cloud scanning on a guideline to a certain extent.

[0005] To address the aforementioned technical problems, this invention provides a method for acquiring conductor point clouds. The method employs a lidar (LiDAR) to acquire conductor point clouds, and the lidar is mounted on a driving device. The driving device controls the lidar to rotate about its pitch and roll axes, respectively, to adjust the position of the lidar's measurement area. The pitch and roll axes are perpendicular to each other, both lying within the lidar's measurement plane and passing through the lidar's center point.

[0006] The data acquisition method includes:

[0007] Multiple representative conductor points on the conductor and a representative tangent corresponding to each representative conductor point are collected; the representative tangent is the conductor tangent that passes through the corresponding representative conductor point on the conductor.

[0008] Based on the representative guide points and the representative tangents, the pitch and roll angles of the lidar are adjusted so that the lidar passes through each of the representative guide points sequentially in a manner in which the measurement area and the corresponding representative tangents are parallel to each other, in order to measure the guide points at different positions on the guide and obtain the position data of each guide point on the guide.

[0009] Optionally, acquiring multiple representative traverse points on the traverse and a representative tangent corresponding to each representative traverse point includes:

[0010] With the roll angle of the lidar controlled to be 0 and the pitch angle changing sequentially within a set pitch angle range, the lidar sequentially scans and measures the coarse position data of multiple coarse measurement points on the guide wire; wherein, the set pitch angle range is the angle range corresponding to each different position point on the guide wire that the measurement area of ​​the lidar completely scans.

[0011] Based on the coarse measurement location data, multiple representative guide points and corresponding representative tangents are determined.

[0012] Optionally, determining multiple representative guide points and corresponding representative tangents based on the coarse measurement location data includes:

[0013] Based on the coarse survey position data corresponding to each coarse survey traverse point, the equation of the coarse survey traverse where the traverse is located is determined by fitting.

[0014] Multiple representative traverse points are selected on the coarse traverse equation, and the representative tangent corresponding to each representative traverse point is determined according to the coarse traverse equation.

[0015] Optionally, the coarse position data of multiple coarse survey points on the guide wire are sequentially scanned and measured by the lidar, including:

[0016] The distance, pitch, roll, and yaw angle data of each coarse survey point on the guide are sequentially scanned and measured by the laser radar and used as the coarse survey position data.

[0017] Wherein, the distance data is the relative distance between the coarse survey traverse point and the lidar;

[0018] The pitch angle data and the roll angle data are the pitch angle and roll angle of the lidar when the lidar measures the coarse survey guide point, respectively.

[0019] The yaw angle is the angle between the line connecting the coarse survey guide point and the center point of the lidar and the axial direction of the lidar's roll axis.

[0020] Optionally, the equation of the coarse traverse where the traverse lies is determined by fitting the coarse location data, including:

[0021] Based on the distance data and yaw angle data in the coarse measurement position data, the first coordinate value of each coarse measurement traverse point in the polar coordinate system is determined; wherein, the origin of the polar coordinate system is the center point of the lidar, and the polar axis and the axis of the roll axis coincide.

[0022] By combining the first coordinate value of each coarse survey traverse point with the corresponding pitch angle data and roll angle data, the second coordinate value of each coarse survey traverse point in a standard three-dimensional rectangular coordinate system is determined; wherein, the origin of the standard three-dimensional rectangular coordinate system is the center point of the lidar, the X-axis is parallel to the roll axis corresponding to the pitch angle of the lidar being 0, and the Y-axis is parallel to the pitch axis corresponding to the roll angle of the lidar being 0;

[0023] Singular value decomposition is used to perform plane fitting on the second coordinate values ​​of each of the coarse survey traverse points to obtain the traverse plane in which the traverse lies.

[0024] A two-dimensional rectangular coordinate system is established in the traverse plane, and each of the coarse traverse points is projected onto the two-dimensional rectangular coordinate system to obtain the third coordinate value corresponding to the coarse traverse point in the two-dimensional rectangular coordinate system;

[0025] The coarse traverse points are fitted based on the third coordinate values ​​to obtain the coarse traverse equation;

[0026] Accordingly, the representative tangent line corresponding to each representative traverse point is determined based on the coarse traverse equation, including:

[0027] Based on the coarse traverse equation, the representative tangent line corresponding to each representative traverse point is determined in the two-dimensional rectangular coordinate system.

[0028] Optionally, multiple representative traverse points are selected on the coarse traverse equation, including:

[0029] Multiple representative traverse points are selected with spacing on the coarse traverse equation; wherein the spacing between two adjacent representative traverse points is not greater than a set spacing.

[0030] Optionally, the pitch and roll angles of the lidar are adjusted based on the representative guide point and the representative tangent, including:

[0031] Based on the representative guide point and the corresponding representative tangent, determine the plane equation of the target plane of the lidar's measurement surface in the standard three-dimensional rectangular coordinate system;

[0032] Based on the plane equation, determine the roll angle adjustment and the pitch angle adjustment corresponding to adjusting the measurement surface of the lidar to the target plane;

[0033] The lidar is adjusted according to the roll angle adjustment and the pitch angle adjustment.

[0034] Optionally, adjusting the lidar based on the roll angle adjustment and the pitch angle adjustment includes:

[0035] When the lidar is adjusted according to the roll angle adjustment amount and the pitch angle adjustment amount, and the representative guide point is not measured in the measurement surface of the lidar, the pitch angle of the lidar is adjusted according to an integer multiple of the pitch angle compensation amount pre-marked by the drive device until the representative guide point falls into the measurement surface of the lidar.

[0036] A point cloud acquisition system for traverse lines, applied to the point cloud acquisition method for traverse lines as described in any of the preceding claims, the acquisition system comprising a lidar and a driving device connected to the lidar;

[0037] The drive device is used to control the position change of the lidar in the measurement area according to the pitch axis and the roll axis respectively; the pitch axis and the roll axis are perpendicular to each other, and both are in the measurement plane of the lidar and pass through the center point of the lidar.

[0038] Optionally, the driving device is a dual-axis gimbal.

[0039] The present invention provides a method and system for acquiring traverse point clouds, which uses a lidar to acquire traverse point clouds, and the lidar is mounted on a driving device. The driving device controls the lidar to rotate about the pitch axis and roll axis, respectively, to adjust the position of the lidar's measurement area. The pitch axis and roll axis are perpendicular to each other and both are within the measurement plane of the lidar and pass through the center point of the lidar. The acquisition method includes: acquiring multiple representative traverse points on the traverse and the representative tangent corresponding to each representative traverse point; the representative tangent is the traverse tangent that passes through the corresponding representative traverse point on the traverse; and adjusting the pitch angle and roll angle of the lidar according to the representative traverse points and the representative tangent, so that the lidar passes through each representative traverse point sequentially in a manner in which the measurement area and the corresponding representative tangent are parallel to each other, to measure the traverse points at different positions on the traverse and obtain the position data of each traverse point on the traverse.

[0040] The driving device for driving the lidar to scan the guideline in this application can not only drive and control the lidar's pitch angle adjustment, but also control the lidar's roll angle adjustment. Therefore, when the lidar scans each representative guideline point on the guideline, by adjusting the lidar's pitch and roll angles, the representative guideline point is positioned within the lidar's measurement area, further ensuring that the measurement area and the corresponding representative tangent of the representative guideline point are parallel to each other. This allows the lidar to scan more guideline points in the adjacent segment of each representative guideline point at once, not only improving the scanning efficiency of measuring points on the guideline to a certain extent, but also increasing the scanning density of points on the guideline to obtain a denser guideline point cloud, thereby improving the accuracy of guideline scanning. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of 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.

[0042] Figure 1 This is a schematic diagram of the laser signal scanning guide wire of a lidar.

[0043] Figure 2 A flowchart illustrating the method for acquiring guideline point clouds provided in this application embodiment;

[0044] Figure 3 This is a schematic diagram of the measurement area of ​​the lidar provided in an embodiment of this application and the scanning guides representing parallel tangents. Detailed Implementation

[0045] like Figure 1 As shown, when a lidar outputs a laser signal to scan various points on a guideline, the laser signal radiates approximately 360 degrees around the lidar device within a plane. This plane is the lidar's measurement surface. When the lidar scans and measures various points on the guideline, the points where this measurement surface intersects with the guideline are the measurable points on that guideline. Furthermore, the measurement surface for laser signal transmission is a relatively thin surface; the measurement area refers to the cross-sectional area where the lidar's measurement surface intersects with the guideline. This measurement area should also be a long, narrow region of a certain width, and the points on the guideline that fall within this measurement area are the measurable points.

[0046] Currently, the conventional method for scanning and measuring guideways using lidar involves maintaining the measurement surface of the lidar's output laser signal roughly perpendicular to the vertical plane. The lidar's elevation angle is adjusted to scan the guideway vertically, meaning the measurement area intersecting the guideway is essentially horizontal. However, the larger the angle between the guideway and the horizontal, the smaller the section of the guideway falling within the measurement area. Since at least half of the guideway has a relatively large angle with the horizontal, the section of the guideway that falls within the measurement area each time is relatively small. This necessitates adjusting the lidar's elevation angle with small increments each time to completely scan all points on the guideway, significantly reducing scanning efficiency. Conversely, increasing the elevation angle adjustment increment each time results in a sparser distribution of scannable points on the guideway, reducing scanning accuracy.

[0047] Therefore, this application provides a technical solution that can ensure both the accuracy and efficiency of conductor scanning measurement.

[0048] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] like Figure 2 and Figure 3 As shown, Figure 2 A flowchart illustrating the method for acquiring guideline point clouds provided in this application embodiment; Figure 3 This is a schematic diagram of the measurement area of ​​the lidar provided in an embodiment of this application and the scanning guides representing parallel tangents.

[0050] In this application, the acquisition of the guide point cloud is achieved using a lidar; and the lidar is connected to a driving device; the driving device can control the lidar to rotate about the pitch axis and roll axis respectively, so as to adjust the position change of the lidar's measurement area; wherein, the pitch axis and roll axis are perpendicular to each other, both within the measurement plane of the lidar and both passing through the center point of the lidar.

[0051] like Figure 1As shown, the pitch axis and roll axis of the lidar are two mutually perpendicular axes located on the measurement surface of the lidar, and the intersection of the pitch axis and roll axis is also the center point of the lidar. When the lidar rotates about the pitch axis and roll axis as rotation centers, the position of the lidar's measurement surface in space can also rotate and change, thereby changing the position and orientation of the measurement area where the measurement surface intersects with the guide wire.

[0052] It should be noted that the pitch axis of the lidar is preferably parallel to the vertical plane containing the suspension rods at both ends of the guide wire. As the lidar rotates around its roll axis, the pitch axis also rotates and changes within this vertical plane. Of course, in practical applications, the fact that the pitch axis and the vertical plane containing the suspension rods are not parallel does not affect the implementation of the technical solution of this application. However, in order to reduce the difficulty of adjusting the pitch and roll angles of the lidar, in practical applications, the angle between the pitch axis and the vertical plane containing the suspension rods can be minimized as much as possible.

[0053] In addition, for ease of explanation, in the following embodiments, the zero position of the pitch angle of the lidar is taken when the pitch axis is in the horizontal direction, and the zero position of the roll angle of the lidar is taken when the roll angle is in the horizontal direction; that is to say, when both the pitch angle and roll angle of the lidar are 0, the measurement surface of the lidar is located in the horizontal plane.

[0054] However, it is understandable that the zero positions corresponding to the pitch and roll angles of the lidar do not necessarily correspond to the pitch and roll axes being in the horizontal direction. Using the pitch and roll axes being in other directions in space as the zero positions of the lidar's pitch and roll angles will not affect the implementation of the technical solution of this application.

[0055] like Figure 2 As shown, Figure 2 This is a flowchart illustrating a method for acquiring guideline point clouds provided in an embodiment of this application. In one specific embodiment of this application, the method for acquiring guideline point clouds may include:

[0056] S11: Collect multiple representative traverse points on the traverse and the representative tangent corresponding to each representative traverse point; the representative tangent is the traverse tangent that passes through the corresponding representative traverse point on the traverse.

[0057] S12: Adjust the pitch and roll angles of the lidar according to the representative traverse points and the representative tangents, so that the lidar passes through each representative traverse point in sequence in a manner in which the measurement area and the corresponding representative tangents are parallel to each other, so as to measure the traverse points at different positions on the traverse and obtain the position data of each traverse point on the traverse.

[0058] like Figure 3As shown, for each point on a conductor, the distances between the tangent to that point and each point in the adjacent conductor segment are relatively small. Since the lidar's measuring surface has a certain thickness, when a point on the conductor falls into the lidar's measuring area, all points in the adjacent conductor segment will also fall into that measuring area and be measured. That is, when the lidar's measuring area is parallel to the tangent of a point, and the point is located within the measuring area, the lidar can measure all points in a nearby conductor segment at once. Clearly, the conductor segment measured in this way is much larger than that measured when the measuring area and the conductor form a certain angle; in other words, the lidar can measure more points in a longer conductor segment at once.

[0059] Therefore, by controlling and adjusting the pitch and roll angles of the lidar through the drive device, the measurement surface of the lidar rotates accordingly, thereby adjusting the measurement area of ​​the lidar sequentially to pass through several representative traverse points on the traverse in a manner parallel to the representative tangents corresponding to each representative traverse point. This allows the lidar to measure the position data of all traverse points within a traverse segment near each representative traverse point in each measurement, thus greatly increasing the length of the traverse segment that can be measured in a single lidar scan and increasing the density of the traverse point cloud that can be measured.

[0060] Furthermore, the representative conductor points on the conductor can be any conductor points randomly selected based on actual needs. For example, multiple conductor points evenly distributed on the conductor can be used as representative conductor points. The distance between two adjacent representative conductor points can also be set according to the length of the conductor segment that can simultaneously fall into the measurement area. For example, the distance between representative conductor points in conductor segments with relatively large radii of curvature can be relatively larger, while the distance between representative conductor points in conductor segments with relatively small radii of curvature can be smaller. The distance between representative conductor points can also be set according to the severity of the bending deformation of the conductor. These are not listed one by one in this embodiment.

[0061] It is understandable that the distance between two adjacent representative guide points reflects the magnitude of the movement of the lidar's measurement area on the guide. Since the measurement area in this embodiment can measure guide points in a longer segment of the guide each time, the lidar can move a larger range of measurement area when measuring each representative guide point in sequence, thereby improving the efficiency of lidar scanning the guide point cloud while ensuring the density of the scanned guide point cloud.

[0062] In summary, the driving device for driving the lidar to scan the guideline in this application can drive and control the lidar's pitch and roll angle adjustments. When the lidar scans each representative guideline point on the guideline, by adjusting the lidar's pitch and roll angles, the representative guideline point is positioned within the lidar's measurement area, further ensuring that the measurement area and the corresponding representative tangent of the representative guideline point are parallel to each other. This allows the lidar to scan more guideline points in the adjacent segment of each representative guideline point at once, which not only improves the scanning efficiency of measuring points on the guideline to a certain extent but also increases the scanning density of points on the guideline, resulting in a denser guideline point cloud and thus improving the accuracy of guideline scanning.

[0063] Based on the above embodiments, in an optional embodiment of this application, the process of obtaining multiple representative traverse points may include:

[0064] S21: With the roll angle of the laser radar controlled to be 0 and the pitch angle changing sequentially within the set pitch angle range, the laser radar sequentially scans and measures the coarse position data of multiple coarse survey points on the guide line.

[0065] The pitch angle range is defined as the angle range corresponding to each different position point on the guide wire through the complete scan of the lidar's measurement area.

[0066] It is understandable that when the lidar scans and determines the coarse measurement position data corresponding to each coarse measurement traverse point, it should be the position point of the coarse measurement traverse point relative to the lidar.

[0067] The coarse position data corresponding to each coarse survey traverse point can include distance data, pitch angle data, roll angle data, and yaw angle data;

[0068] Among them, the distance data is the relative distance between the coarse survey traverse points and the lidar;

[0069] The pitch angle data and roll angle data are the pitch angle and roll angle of the lidar when measuring the coarse survey traverse points, respectively; obviously, in this embodiment, the roll angle corresponding to each coarse survey traverse point is 0.

[0070] The yaw angle is the angle between the line connecting the coarse survey traverse point and the center point of the lidar and the axis of the lidar's roll axis.

[0071] S22: Determine multiple representative traverse points and corresponding representative tangents based on the rough measurement location data.

[0072] To roughly determine the position of the conductor in space, and thus identify multiple representative conductor points and corresponding representative tangents, this embodiment uses a lidar coarse survey to determine the conductor's spatial distribution. To simplify the complexity of the coarse survey, this embodiment keeps the lidar's roll angle at 0, only changing the pitch angle. Clearly, the length direction of the lidar's measurement area is horizontal at this point, and as the lidar scans vertically, this measurement area can move vertically to scan various points on the conductor.

[0073] After obtaining the positions of each coarse traverse point through lidar scanning, it is clear that the approximate spatial distribution of the entire traverse can be determined. Thus, several representative traverse points can be selected on the traverse, and the representative tangent passing through each representative traverse point can be determined.

[0074] Furthermore, the lidar scans and measures the conductor at predetermined time intervals. If the wind speed and other environmental factors in the conductor's environment do not change drastically in a short period, the conductor's position in space will not change significantly. In this case, it is also possible to directly select a portion of the conductor points from the previously measured conductor point cloud as coarse conductor points to determine representative conductor points and representative tangents, thus achieving the technical solution of this application. Of course, in practical applications, other methods or devices may be used to perform coarse measurements of the conductor and determine its spatial distribution; this application does not impose specific restrictions on this.

[0075] After obtaining the coarse position data corresponding to the coarse traverse points that characterize the approximate spatial distribution of the traverse, the following can be further included:

[0076] Based on the coarse survey position data corresponding to each coarse survey traverse point, the equation of the coarse survey traverse where the traverse is located is determined by fitting.

[0077] Multiple representative traverse points are selected on the coarse traverse equation, and the representative tangent corresponding to each representative traverse point is determined according to the coarse traverse equation.

[0078] After determining the coarse location data of the coarse traverse points in space, a coarse traverse equation representing the spatial distribution of the traverse can be fitted and determined. Based on this equation, several suitable representative traverse points can be selected on the traverse, for example, multiple representative traverse points can be selected at equal intervals along the traverse; and based on the equation, the representative tangent corresponding to each representative traverse point can be determined. Given the known coarse location data of each coarse traverse point, the coarse traverse equation can be directly fitted and determined using methods similar to least squares or other linear fitting techniques.

[0079] In another optional embodiment of this application, the process of determining the equation of the coarse traverse may include:

[0080] S31: Based on the distance data and yaw angle data in the coarse measurement position data, determine the first coordinate value of each coarse measurement traverse point in the polar coordinate system; wherein, the origin of the polar coordinate system is the center point of the lidar, and the axes of the polar axis and the roll axis coincide.

[0081] S32: Combine the first coordinate value of each coarse survey traverse point with the corresponding pitch angle data and roll angle data to determine the second coordinate value of each coarse survey traverse point in the standard three-dimensional rectangular coordinate system.

[0082] In this system, the origin of the standard three-dimensional rectangular coordinate system is the center point of the lidar. The X-axis is parallel to the roll axis corresponding to the lidar's pitch angle of 0, and the Y-axis is parallel to the pitch axis corresponding to the lidar's roll angle of 0.

[0083] Obviously, when the roll axis and pitch axis of the lidar are horizontal, the zero points of the roll angle and pitch angle of the lidar are the same, and the Z-axis of the standard rectangular coordinate system is the vertical direction.

[0084] S33: Use singular value decomposition to perform plane fitting on the second coordinate values ​​of each coarse survey traverse point to obtain the traverse plane in which the traverse lies.

[0085] S34: Establish a two-dimensional rectangular coordinate system in the traverse plane, and project each coarse traverse point into the two-dimensional rectangular coordinate system to obtain the third coordinate value of the coarse traverse point in the two-dimensional rectangular coordinate system.

[0086] S35: Fit the coarse traverse points based on the third coordinate value to obtain the coarse traverse equation.

[0087] Accordingly, determining the representative tangent corresponding to each representative traverse point can include:

[0088] Based on the equation of the coarse traverse, the representative tangent line corresponding to each representative traverse point is determined in a two-dimensional rectangular coordinate system.

[0089] In the polar coordinate system, the first coordinate value of the coarse survey traverse point is expressed as: Where, ρ i and These represent the distance and yaw angle data for the i-th coarse survey traverse point, respectively; i = 1, 2, 3, ..., N, where N is the number of coarse survey traverse points collected. To achieve coordinate value conversion between the polar coordinate system and the standard three-dimensional rectangular coordinate system, a three-dimensional rectangular coordinate system for the lidar can be further established with the roll axis as the X-axis and the pitch axis as the Y-axis. Therefore, the coordinate values ​​of the i-th coarse survey traverse point in the lidar's three-dimensional rectangular coordinate system are... and

[0090] Based on this, according to the elevation angle data θ corresponding to the i-th coarse survey traverse point i Construct the pitch transformation matrix R y (θ i )for:

[0091]

[0092] Construct the roll transformation matrix R based on the roll angle data corresponding to the i-th coarse survey traverse point. x (γ i )for:

[0093]

[0094] Therefore, the second coordinate value of the i-th coarse survey traverse point in the standard three-dimensional rectangular coordinate system is:

[0095]

[0096] After determining the second coordinate values ​​of each coarse traverse point in the standard three-dimensional rectangular coordinate system, the equation of the coarse traverse can be fitted. In this embodiment, it is further considered that fitting a curve in three-dimensional space based on discrete points is relatively difficult. Therefore, this embodiment transforms the curve fitting in three-dimensional space into curve fitting in a two-dimensional plane, reducing the difficulty of the coarse traverse equation.

[0097] Based on the second coordinate values ​​of each coarse traverse point in the standard three-dimensional rectangular coordinate system, the centroid coordinate values ​​of the point cloud of each coarse traverse point are constructed as follows:

[0098] Based on the centroid coordinates of the point cloud, the decentralized matrix corresponding to each coarse survey traverse point is constructed as follows:

[0099]

[0100] Perform singular value decomposition on matrix D:

[0101] Among them, U and V T All are orthogonal matrices, with S being a diagonal matrix containing singular values ​​on its diagonal, where the singular values ​​σ1 ≥ σ2 ≥ σ3; the singular vectors corresponding to the singular values ​​σ1, σ2, and σ3 are v1, v2, and v3, respectively. Clearly, the plane formed by v1 and v2 is the traverse plane containing the fitted points of each coarse survey traverse. Therefore, the directions of v1 and v2 can be defined as the X-axis and Y-axis directions, respectively, with the centroid of the point cloud as the reference point. Establish a two-dimensional rectangular coordinate system on the plane containing the traverse plane, with the origin as the origin. Based on this, project all coarse traverse points onto this traverse plane. The coordinate matrix formed by the coordinates of the projection points of each coarse traverse point onto the traverse plane in the two-dimensional rectangular coordinate system can then be represented as:

[0102]

[0103] It should be noted that most of the traverse points on the traverse are located in the same plane, but when the traverse bends in a complex manner, a small number of traverse points may fluctuate up and down within the plane. In order to simplify the process of determining the coarse traverse equation, this embodiment performs plane fitting on each coarse traverse point to obtain the traverse plane where some traverse points on the traverse are located, and projects the coarse traverse points that are not located on the traverse plane onto the traverse plane. The coarse traverse equation is then fitted using the projection points of each coarse traverse point in the traverse plane, which simplifies the fitting difficulty of the coarse traverse equation to a certain extent.

[0104] Based on this, after determining the projection points of each coarse survey traverse point on the traverse plane, the reason for further establishing a two-dimensional rectangular coordinate system in the traverse plane and fitting the coordinate values ​​of the projection points of each coarse survey traverse point on the traverse plane in this two-dimensional rectangular coordinate system to determine the coarse survey traverse equation is equivalent to changing the curve fitting distributed in three-dimensional space into a curve fitting distributed in two-dimensional space, reducing the dimension of the curve distribution, which also reduces the difficulty of fitting the coarse survey traverse equation.

[0105] Taking the projection of the traverse onto the traverse plane as a parabola as an example, the equation of this coarse traverse survey can be expressed as: y(x)=A1x 2 +B1x+C1.

[0106] Constructing a matrix Let w = [A1, B1, C1] T Then Aw≈v y Therefore, we can obtain w = (A T A) - 1 A T v y Therefore, based on the coordinates of the projection points of each coarse survey traverse point in a two-dimensional rectangular coordinate system, w = [A1, B1, C1] can be determined. T That is, the equation of the rough survey traverse is determined.

[0107] Of course, in practical applications, determining the traverse plane based on the fitting of each coarse traverse point does not necessarily have to be done by singular value decomposition. Other methods can also be used, and this application does not impose specific restrictions on this.

[0108] The equation of the coarse traverse is determined by fitting in a two-dimensional rectangular coordinate system. After selecting several representative traverse points on the coarse traverse equation, the tangents of each representative traverse point can also be directly determined in the two-dimensional rectangular coordinate system based on the coarse traverse equation, thereby reducing the difficulty of determining the representative tangents.

[0109] Several points are selected on the coarse traverse equation as representative traverse points q. j =(q jx q jy ), where q jx q jy Let be the coordinates of the j-th representative traverse point in a two-dimensional rectangular coordinate system, where j = 1, 2, ..., n, and n is the total number of representative traverse points.

[0110] Taking the parabola equation as an example, the equation of the coarse traverse line can be expressed as follows in a two-dimensional rectangular coordinate system: The equation of the tangent line corresponding to the j-th representative traverse point can be:

[0111] Therefore, the tangent direction is: [1, 2A1q] jx +B1];

[0112] The location of the tangent point is Clearly, the location of this tangent point is also the location of the conductor point.

[0113] In another optional embodiment of this application, the process of further determining the pitch and roll angles of the lidar based on determining the representative guide point and the representative tangent may include:

[0114] Based on the representative guide points and the corresponding representative tangents, determine the plane equation of the target plane of the lidar measurement surface in the standard three-dimensional rectangular coordinate system.

[0115] Based on the plane equation, determine the roll angle and pitch angle adjustment amounts corresponding to adjusting the measurement surface of the lidar to the target plane;

[0116] The lidar is adjusted based on the roll angle and pitch angle adjustments.

[0117] It is understood that the target plane in this embodiment is the plane in which the measurement surface of the lidar is located when the measurement area of ​​the lidar passes through the representative guide point and is parallel to the corresponding representative tangent.

[0118] Taking the equation of the coarse traverse as a parabola equation as an example, the tangent direction and the position of the tangent point in the two-dimensional rectangular coordinate system are further transformed to the standard three-dimensional rectangular coordinate system; thus, in the standard three-dimensional rectangular coordinate system, the tangent direction representing the tangent can be determined as M = [1, (2A1q jx +B1), 0]·V T=v1+(2A1q jx +B1)v2; and the position of the tangent point of the conductor is...

[0119] Therefore, the plane equation of the target plane in the standard three-dimensional rectangular coordinate system can be further determined as: (M×T)·[xyz] T =N[xyz] T =n x x+n y y+n z z = 0.

[0120] Clearly, the pitch and roll angles of the target plane relative to the lidar in its zero-point state (both pitch and roll angles are 0) are the pitch and roll angle adjustments corresponding to the lidar's measurement surface being adjusted to the target plane. Therefore, the pitch angle adjustment is: The roll angle is:

[0121] Additionally, it should be noted that in order to drive the lidar, such as a dual-axis gimbal, there may often be errors in the actual process of adjusting the lidar's pitch angle. To ensure that the lidar's measurement area passes through the representative guide point, this is mainly achieved by adjusting the pitch angle. Therefore, if the pitch angle is adjusted too small, it may directly cause the representative guide point on the guide to fail to fall into the measurement area, and thus the guide point may not be measured at all.

[0122] Therefore, in another optional embodiment of this application, the process of adjusting the lidar according to the roll angle adjustment and pitch angle adjustment may further include:

[0123] When the lidar is adjusted according to the roll angle adjustment and pitch angle adjustment, if the representative guide point is not measured in the lidar's measurement plane, the pitch angle of the lidar is adjusted according to an integer multiple of the pitch angle compensation amount pre-marked by the drive device until the representative guide point falls into the lidar's measurement plane.

[0124] In this embodiment, the pitch angle error during the pitch angle adjustment process of the lidar driven by the driving device is marked in advance, thereby determining the pitch angle compensation amount. During the actual adjustment of the lidar pitch angle, the pitch angle adjustment amount of the lidar can be compensated and corrected according to the pitch angle compensation amount. For example, the pitch angle of the lidar can be increased by double the pitch angle compensation amount first, and it can be determined whether the representative guide point can be measured in the measurement plane of the lidar. If not, the pitch angle of the lidar is increased by the pitch angle compensation amount again. This process is repeated until the representative guide point falls into the measurement plane, thereby ensuring that the representative guide point can fall into the measurement area.

[0125] This application also provides a conductor point cloud acquisition system, applied to the conductor point cloud acquisition method described in any of the preceding claims, the acquisition system including a lidar and a driving device connected to the lidar;

[0126] The driving device is used to control the position change of the measurement area of ​​the lidar according to the pitch axis and the roll axis respectively; the pitch axis and the roll axis are perpendicular to each other, and both are in the measurement plane of the lidar and pass through the center point of the lidar.

[0127] Alternatively, the drive device can be a dual-axis gimbal.

[0128] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that the elements inherent in a process, method, article, or apparatus that includes a list of elements are included. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Additionally, portions of the technical solutions provided in the embodiments of this application that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0129] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for acquiring point clouds of conductors, characterized in that, A lidar is used to collect point clouds of a conductor, and the lidar is mounted on a driving device. The driving device is used to control the lidar to rotate about the pitch axis and the roll axis, respectively, so as to adjust the position of the lidar's measurement area. The pitch axis and the roll axis are perpendicular to each other, and both are within the measurement plane of the lidar and pass through the center point of the lidar. The data acquisition method includes: Multiple representative conductor points on the conductor and a representative tangent line corresponding to each representative conductor point are collected; the representative tangent line is the tangent line passing through the corresponding representative conductor point on the conductor. Based on the representative guide points and the representative tangents, the pitch and roll angles of the lidar are adjusted so that the lidar passes through each of the representative guide points in sequence with the measurement area and the corresponding representative tangents parallel to each other, in order to measure the guide points at different positions on the guide and obtain the position data of each guide point on the guide. The pitch and roll angles of the lidar are adjusted based on the representative guide point and the representative tangent, including: Based on the representative guide points and the corresponding representative tangents, the plane equation of the target plane of the lidar measurement surface in the standard three-dimensional rectangular coordinate system is determined. Based on the plane equation, determine the roll angle and pitch angle adjustment amounts corresponding to adjusting the measurement surface of the lidar to the target plane; The lidar is adjusted according to the roll angle adjustment and the pitch angle adjustment. Adjusting the lidar according to the roll angle adjustment and the pitch angle adjustment includes: When the lidar is adjusted according to the roll angle adjustment amount and the pitch angle adjustment amount, and the representative guide point is not measured in the measurement surface of the lidar, the pitch angle of the lidar is adjusted according to an integer multiple of the pitch angle compensation amount pre-marked by the drive device until the representative guide point falls into the measurement surface of the lidar.

2. The method for acquiring point clouds of guide lines as described in claim 1, characterized in that, Acquire multiple representative traverse points on the traverse and the representative tangent corresponding to each representative traverse point, including: With the roll angle of the lidar controlled to be 0 and the pitch angle changing sequentially within a set pitch angle range, the lidar sequentially scans and measures the coarse position data of multiple coarse measurement points on the guide wire; wherein, the set pitch angle range is the angle range corresponding to each different position point on the guide wire that the measurement area of ​​the lidar completely scans. Based on the coarse measurement location data, multiple representative guide points and corresponding representative tangents are determined.

3. The method for acquiring point clouds of guide lines as described in claim 2, characterized in that, Based on the coarsely measured position data, multiple representative guide points and corresponding representative tangents are determined, including: Based on the coarse survey position data corresponding to each coarse survey traverse point, the equation of the coarse survey traverse where the traverse is located is determined by fitting. Multiple representative traverse points are selected on the coarse traverse equation, and the representative tangent corresponding to each representative traverse point is determined according to the coarse traverse equation.

4. The method for acquiring point clouds of guide lines as described in claim 3, characterized in that, The coarse position data of multiple coarse survey points on the guide wire are obtained by sequentially scanning with the laser radar, including: The distance, pitch, roll, and yaw angle data corresponding to each coarse survey traverse point on the traverse are sequentially scanned and measured by the lidar and used as the coarse survey position data. Wherein, the distance data is the relative distance between the coarse survey traverse point and the lidar; The pitch angle data and the roll angle data are the pitch angle and roll angle of the lidar when the lidar measures the coarse survey guide point, respectively. The yaw angle is the angle between the line connecting the coarse survey guide point and the center point of the lidar and the axial direction of the lidar's roll axis.

5. The method for acquiring guideline point clouds as described in claim 4, characterized in that, The equation of the coarse traverse where the traverse is located is determined by fitting the coarse location data, including: Based on the distance data and yaw angle data in the coarse measurement position data, the first coordinate value of each coarse measurement traverse point in the polar coordinate system is determined; wherein, the origin of the polar coordinate system is the center point of the lidar, and the polar axis and the axis of the roll axis coincide. By combining the first coordinate value of each coarse survey traverse point with the corresponding pitch angle data and roll angle data, the second coordinate value of each coarse survey traverse point in a standard three-dimensional rectangular coordinate system is determined; wherein, the origin of the standard three-dimensional rectangular coordinate system is the center point of the lidar, the X-axis is parallel to the roll axis corresponding to the pitch angle of the lidar being 0, and the Y-axis is parallel to the pitch axis corresponding to the roll angle of the lidar being 0; Singular value decomposition is used to perform plane fitting on the second coordinate values ​​of each of the coarse survey traverse points to obtain the traverse plane in which the traverse lies. A two-dimensional rectangular coordinate system is established in the traverse plane, and each of the coarse traverse points is projected onto the two-dimensional rectangular coordinate system to obtain the third coordinate value of the coarse traverse point in the two-dimensional rectangular coordinate system; The coarse traverse points are fitted based on the third coordinate values ​​to obtain the coarse traverse equation; Accordingly, the representative tangent line corresponding to each representative traverse point is determined based on the coarse traverse equation, including: Based on the coarse traverse equation, the representative tangent line corresponding to each representative traverse point is determined in the two-dimensional rectangular coordinate system.

6. The method for acquiring point clouds of guide lines as described in claim 3, characterized in that, Multiple representative traverse points are selected on the coarse traverse equation, including: Multiple representative traverse points are selected with spacing on the coarse traverse equation; wherein the spacing between two adjacent representative traverse points is not greater than a set spacing.

7. A system for acquiring point clouds of conductors, characterized in that, The method for acquiring point clouds of conductors as described in any one of claims 1 to 6, wherein the acquisition system includes a lidar and a driving device connected to the lidar; The drive device is used to control the lidar to rotate on the pitch axis and the roll axis respectively, so as to adjust the position change of the measurement area; the pitch axis and the roll axis are perpendicular to each other, and both are in the measurement plane of the lidar and pass through the center point of the lidar.

8. The point cloud acquisition system for guide lines as described in claim 7, characterized in that, The drive device is a dual-axis gimbal.

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