A method and device for constructing three-dimensional geometric shape of rail space

Abstract

The present invention relates to a method and device for constructing a three-dimensional geometric shape of a rail space, comprising: obtaining motion state information of a rail measuring device and rail laser scanning data; establishing a three-dimensional point cloud model of the rail according to the laser scanning data; judging the change point of the rail design linear shape based on the motion state information of the rail measuring device; extracting the midpoint of the top of the rail section in the model, fitting the rail top centerline parameters according to the curve equation corresponding to the track linear shape, generating the rail top centerline, and optimizing the spatial position of the rail top centerline by combining the angular velocity and linear velocity information; combining the rail section geometric design parameters and the rail top centerline coordinates to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and finally reconstructing the three-dimensional shape of the rail space. The present invention can realize more accurate measurement of rail geometric state parameters, and can also calculate the rail geometric state parameters at any length interval and any position.

Description

Technical Field

[0001] The present invention relates to the technical field of data measurement, and in particular to a method and device for constructing a three-dimensional geometric shape of a rail space by combining motion state information with a three-dimensional point cloud. Background Art

[0002] Railway is an important national infrastructure, a major artery of the national economy and a popular means of transportation. The large-scale development of high-speed railways with advantages such as large transportation capacity, safety and comfort, all-weather transportation, environmental friendliness and sustainability is the only way and inevitable choice to solve the contradiction of insufficient supply of transportation capacity in my country under the current energy and environmental constraints. With the large number of high-speed railways put into operation, ensuring the system safety and sustainability of high-speed railways as a whole is a major challenge facing high-speed railways, among which the impact of railway track unevenness is particularly important. Track unevenness refers to the deviation between the actual size, geometry and position of the track and its ideal state. The existence of track unevenness will introduce noise and vibration, affect the comfort of driving, and cause the railway wheel-rail force to increase, accelerate the damage of the wheel-rail and the railway, increase maintenance costs, and even cause driving accidents in severe cases. The track unevenness state needs to be accurately measured to guide railway maintenance personnel to repair it. Therefore, how to accurately measure the specific parameters of track unevenness has become the focus of research.

[0003] The combination of total station and track inspection trolley is an important method at present. The total station is used to set up stations freely at certain intervals. By looking back at multiple CPⅢ control points, the absolute coordinates of the total station are calculated, the detection equipment is positioned, and then the geometric information of the rail is reconstructed through the spatial state of the detection equipment, and the absolute geometric unevenness of the rail is calculated on this basis. However, the "stop-and-go" working mode of this method seriously limits its work efficiency and requires high specialized knowledge and skills of the measurement operator.

[0004] Another important method is to use inertial measurement sensors or optoelectronic devices to measure separately to obtain short-distance relative geometric dimension parameters of the track. For example, a gyroscope-based measurement vehicle for measuring track geometry irregularities is developed. In addition, there is also a method that uses the collimation characteristics of lasers to perform high-precision detection and evaluation of track geometry irregularities. Such methods cannot detect and eliminate the influence of gross errors, and optical instruments have strict requirements on the environment and are easily affected by the atmosphere, temperature, etc.

[0005] In addition, there are methods that use visual measurement technology to calculate and analyze parameters related to track irregularity. However, two-dimensional image detection lacks geometric and depth information and can only obtain some geometric parameters from a certain direction. This method is usually used to identify superficial defects such as partial damage on the rail surface. Summary of the invention

[0006] In view of the technical problems existing in the prior art, the present invention provides a method and device for constructing the three-dimensional geometric shape of rail space by combining motion state information with three-dimensional point cloud. Firstly, the three-dimensional spatial distribution information of the rail point cloud is used to reconstruct the rail top centerline, and then the motion state information measured by the inertial sensor built into the detection equipment is used to infer the track linear parameters, and the two are fused to optimize the spatial position and shape of the rail top centerline, so as to achieve more accurate measurement of the track linear shape and finally achieve accurate calculation of the track geometric state parameters.

[0007] The technical solution of the present invention to solve the above technical problems is as follows:

[0008] In a first aspect, the present invention provides a method for constructing a three-dimensional geometric shape of a rail space, comprising:

[0009] Acquire motion state information of the rail measuring device and laser scanning data collected by the rail measuring device; the motion state information includes angular velocity and linear velocity;

[0010] Establishing a three-dimensional point cloud model of the rail according to the laser scanning data and extracting the midpoint of the top of the rail section in the model;

[0011] Determine the rail design linear change point based on the motion state information of the rail measuring device, and segment the rail linear shape according to the linear change point; the rail linear shape includes a straight line, a transition curve and a circular curve;

[0012] Fitting the rail top centerline parameters according to the curve equation corresponding to the track line shape to generate the rail top centerline, and optimizing the spatial position of the rail top centerline using the angular velocity and linear velocity information;

[0013] The geometric design parameters of the rail section and the optimized rail top centerline coordinates are combined to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and construct the three-dimensional geometric shape of the rail space.

[0014] Further, based on the motion state information of the rail measuring device, the rail design linear change point is determined, and the track linear segmentation is performed according to the linear change point, including:

[0015] Extracting the position information of the rail measuring equipment from the motion state information;

[0016] If the heading angle is constant and the roll angle is 0, it is judged that the rail measuring device is located in the straight section of the track;

[0017] If the heading angle changes constantly and the roll angle is constant and not 0, it is judged that the rail measuring device is located in the circular curve section of the track;

[0018] If the heading angle change speed increases and the absolute value of the roll angle gradually increases, it is judged that the rail measuring equipment is located in the transition curve section from the straight track section to the circular curve section;

[0019] If the changing speed of the heading angle decreases and the absolute value of the roll angle gradually decreases, it is judged that the rail measuring equipment is located in the transition curve section from the circular curve section to the straight section of the track.

[0020] Furthermore, the rail top centerline parameters are fitted according to the curve equation corresponding to the track line shape to generate the rail top centerline, including:

[0021] The straight line segment linear formula and the circular curve fitting adjustment solution basic relationship are used to fit the straight line segment and the circular curve segment track centerline respectively;

[0022] Based on the track centerline parameters of the adjacent straight and circular curve segments before and after the transition curve segment, its parameters are determined according to the linear law of the transition curve.

[0023] Furthermore, the angular velocity and linear velocity information is used to optimize the spatial position of the centerline of the rail top, including:

[0024] Obtain the angular velocity and linear velocity data of the rail measuring equipment at the target mileage, as well as the midline point cloud coordinates of the fitted point cloud;

[0025] The first track curvature radius and the corresponding curvature radius variance are calculated by using the angular velocity and linear velocity data of the rail measuring equipment, and the second track curvature radius and the corresponding curvature radius variance are calculated by using the fitting rail top centerline point cloud coordinates;

[0026] Optimizing and solving the curvature radius at the target mileage by using the first track curvature radius and the corresponding curvature radius variance and the second track curvature radius and the corresponding curvature radius variance;

[0027] The curvature radius at the target mileage is substituted into the circular curve or transition curve fitting formula as a priori linear parameter of the rail, and the rail top centerline is subjected to overall constraint adjustment to determine the spatial position of the rail top centerline of the circular curve segment or transition curve segment.

[0028] Furthermore, the curvature radius at the target mileage is solved according to the following formula:

[0029]

[0030] In the formula, R 0 is the curvature radius at the target mileage, is the first track curvature radius and the corresponding curvature radius variance, is the radius of curvature of the second track and the corresponding variance of the curvature radius.

[0031] Furthermore, the first track curvature radius and the corresponding curvature radius variance are calculated by using the angular velocity and linear velocity data of the rail measuring equipment. The calculation method is as follows:

[0032]

[0033] In the formula, is the first track curvature radius, V is the linear speed, is the angular velocity in radians;

[0034] Based on the curvature radius error propagation formula:

[0035] ,

[0036] Get the error propagation coefficient and , and use the error propagation coefficient to calculate the variance corresponding to the first track curvature radius :

[0037]

[0038] , are the linear velocity variance and angular velocity variance respectively.

[0039] Furthermore, the geodetic coordinates of key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage are calculated by combining the geometric design parameters of the rail section and the coordinates of the centerline of the rail top, including:

[0040] Establish a rail section coordinate system, with the midpoint of the line connecting the midpoints of the left and right rail tops at the target mileage as the origin of the coordinate system, the X-axis points to the midpoint of the right rail top, the vertical direction is the Y-axis, pointing to the sky as positive, and the Z-axis points to the forward direction to form a right-hand rectangular coordinate system with the X and Y axes;

[0041] Constructing a first coordinate conversion matrix from the rail measuring device coordinate system to the navigation coordinate system and a second coordinate conversion matrix from the rail section coordinate system to the rail measuring device coordinate system;

[0042] According to the geometric design parameters of the rail section, based on the origin of the rail section coordinate system and the first coordinate transformation matrix and the second coordinate transformation matrix, the geodetic coordinates of any key point of the rail section are calculated;

[0043] If the target mileage is located on a circular curve segment, the heading angle at the target mileage is calculated using the following formula: , Pitch angle , Roll Angle :

[0044] ,

[0045] If the target mileage is located on a transition curve, the heading angle at the target mileage is calculated using the following formula: , Pitch angle , Roll Angle :

[0046]

[0047] In the formula, S i Indicates the mileage value at the target mileage. S 0. S t They represent the starting mileage value and the ending mileage value of the track segment where the target mileage is located. , , are the heading angle, pitch angle, and roll angle of the starting point of the track segment where the target mileage is located. , , They are respectively the heading angle, pitch angle, and roll angle of the end point of the track segment where the target mileage is located.

[0048] In a second aspect, the present invention provides a device for constructing a three-dimensional geometric shape of a rail space, comprising:

[0049] A data acquisition module, which acquires the motion state information of the rail measuring device and the laser scanning data collected by the rail measuring device; the motion state information includes angular velocity and linear velocity;

[0050] A model building module, which builds a three-dimensional point cloud model of the rail according to the laser scanning data and extracts the midpoint of the top of the rail section in the model;

[0051] A track segmentation module, which determines the rail design line shape change point based on the motion state information of the rail measuring device, and performs track line shape segmentation according to the line shape change point; the track line shape includes a straight line, a transition curve and a circular curve;

[0052] The rail top centerline generation and optimization module performs rail top centerline parameter fitting according to the curve equation corresponding to the track line shape to generate the rail top centerline, and optimizes the spatial position of the rail top centerline using the angular velocity and linear velocity information;

[0053] The calculation module combines the geometric design parameters of the rail section and the optimized rail top centerline coordinates to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and constructs the three-dimensional geometric shape of the rail space.

[0054] In a third aspect, the present invention provides an electronic device, comprising:

[0055] Memory for storing computer software programs;

[0056] The processor is used to read and execute the computer software program, thereby realizing the method for constructing the three-dimensional geometric shape of the rail space described in the first aspect of the present invention.

[0057] In a fourth aspect, the present invention provides a non-transitory computer-readable storage medium, wherein the storage medium stores a computer software program, and when the computer software program is executed by a processor, the method for constructing a three-dimensional geometric shape of a rail space as described in the first aspect of the present invention is implemented.

[0058] The beneficial effects of the present invention are as follows: 1) The present invention uses the motion state information of the equipment to establish the geometric shape parameters of the rail, and fuses it with the fitted derailment top center line in the rail point cloud, so as to achieve more accurate measurement of the geometric state parameters of the rail.

[0059] 2) The present invention adopts a method of combining the rail section geometry model, the centerline point of the rail top surface and the coordinates of the key points of the track section to calculate the track geometry state parameters at any length interval and any position. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 A schematic diagram of a flow chart of a method for constructing a three-dimensional geometric shape of a rail space provided by an embodiment of the present invention;

[0061] Figure 2 A schematic diagram of the structure of a device for constructing a three-dimensional geometric shape of a rail provided in an embodiment of the present invention;

[0062] Figure 3 A schematic diagram of an electronic device according to an embodiment of the present invention;

[0063] Figure 4 A schematic diagram of an embodiment of a computer-readable storage medium provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0064] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0065] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0066] In the description of the present application, the term "for example" is used to mean "used as an example, illustration or description". Any embodiment described as "for example" in the present application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any technician in the field to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present invention can be implemented without using these specific details. In other examples, well-known structures and processes will not be elaborated in detail to avoid unnecessary details to obscure the description of the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in the present application.

[0067] like Figure 1 As shown, an embodiment of the present invention provides a method for constructing a three-dimensional geometric shape of a rail space, comprising:

[0068] S100, obtaining the motion state information of the rail measuring equipment and the laser scanning data collected by the rail measuring equipment. The rail measuring equipment is implemented by a mobile three-dimensional laser scanning system. The mobile three-dimensional laser scanning system is used for track measurement and is generally composed of components such as a GNSS antenna, a laser scanner, a laser inertial navigation, a wheel encoder, and a gyroscope. The rail measuring equipment moves on the rails, and the rail point cloud and the motion state information of the equipment are collected through the above components. The motion state information includes angular velocity and linear velocity, and may also include positioning information, and the positioning information may be determined jointly by GNSS and laser inertial navigation.

[0069] S200, establishing a three-dimensional point cloud model of the rail according to the laser scanning data and extracting the midpoint of the top of the rail section in the model.

[0070] The laser point cloud data includes the point cloud position coordinates. Since the manufacture of rails must strictly comply with relevant standards, it relies on the design model of the rails. A three-dimensional point cloud model of the rails can be constructed based on the laser point cloud data. The construction process belongs to the existing technology and will not be repeated here.

[0071] S300, judging the rail design line shape change points based on the motion state information of the rail measuring equipment, and segmenting the track line shape according to the line shape change points; the track line shape includes a straight line, a transition curve and a circular curve.

[0072] Extracting the position information of the rail measuring equipment from the motion state information;

[0073] If the heading angle is constant and the roll angle is 0, it is judged that the rail measuring device is located in the straight section of the track;

[0074] If the heading angle changes constantly and the roll angle is constant and not 0, it is judged that the rail measuring device is located in the circular curve section of the track;

[0075] If the heading angle change speed increases and the absolute value of the roll angle gradually increases, it is judged that the rail measuring equipment is located in the transition curve section from the straight track section to the circular curve section;

[0076] If the changing speed of the heading angle decreases and the absolute value of the roll angle gradually decreases, it is judged that the rail measuring equipment is located in the transition curve section from the circular curve section to the straight section of the track.

[0077] S400, fitting the rail top centerline parameters according to the curve equation corresponding to the track line shape to generate the rail top centerline, and optimizing the spatial position of the rail top centerline by using the angular velocity and linear velocity information.

[0078] Fitting the track centerline parameters using curve equations can effectively eliminate the gross error caused by sudden changes due to some unexpected situations. First, the straight line segment and circular curve segment track centerline are fitted using the straight line segment linear formula and the circular curve fitting adjustment solution basic relationship; then, based on the track centerline parameters of the adjacent straight line segment and circular curve segment before and after the transition curve segment, its parameters are determined according to the transition curve linear law.

[0079] The orbit linear fitting formula is as follows:

[0080] a. Linear formula for the straight line stage

[0081] (1)

[0082] x i , y i They are respectively i The horizontal and vertical coordinates of the center point. Let the straight line pass through the selected center point of the rail top. The fitting process is to solve the parameters while ensuring that the sum of squares of the fitting residuals is minimized. a and b , the criterion formula is:

[0083] (2)

[0084] b. Circular curve stage fitting and expression formula

[0085] The basic relationship of circular curve fitting adjustment solution is as follows:

[0086] (3)

[0087] A and B are the horizontal and vertical coordinates of the center of the circle, R is the radius of the circle, , , are the correction values ​​of the center coordinates and radius estimates, respectively. The least squares principle is also used to solve the three parameters by adjustment. The constraint criteria are:

[0088] (4)

[0089] Since the fitting is based on the relative shape information between the center lines of the rail tops in the normal area, it is believed that there are no factors such as gross errors, so the weights are set to be equal in the adjustment.

[0090] Parameters to be requested for:

[0091] (5)

[0092] The same iterative calculation is used. After each adjustment calculation,

[0093]

[0094] Then recalculate until the absolute value of the parameter correction number obtained twice is less than the fixed threshold or the number of adjustments exceeds the limit, then the calculation is terminated. The method for determining the threshold is based on the track curvature radius and is determined based on the design specifications of the track types such as high-speed rail, ordinary rail, and subway corresponding to the measurement section. In this embodiment, the threshold value of the number of adjustments is set to 5, and usually two to three adjustments can obtain stable and accurate parameters to be determined.

[0095] c. Easing curve stage fitting and expression formula

[0096] A transition curve is a transition line between a straight line and a circular curve. Its curvature is inversely proportional to the distance from the starting point of the straight line. The curvature at the starting point is infinite, and the curvature at the transition point is equal to the curvature of the circular curve. In railway design, transition curves are usually described by the radial spiral formula, and the corresponding curve equation is:

[0097] (6)

[0098] in, C = R·l 0, R is the radius of curvature of the circular curve, l 0 is the total length of the transition curve, l i The length of the curve from the current point to the straight and smooth point. The parameters of the smooth curve are difficult to determine by direct fitting. First, fit the adjacent straight lines and circular curves, and then determine them uniquely according to the linear law of the smooth curve.

[0099] After completing the rail top centerline parameter fitting, the angular velocity and linear velocity information are used to optimize the rail top centerline spatial position, specifically including:

[0100] Obtain the angular velocity and linear velocity data of the rail measuring equipment at the target mileage, as well as the midline point cloud coordinates of the fitted point cloud;

[0101] The first track curvature radius and the corresponding curvature radius variance are calculated by using the angular velocity and linear velocity data of the rail measuring equipment, and the second track curvature radius and the corresponding curvature radius variance are calculated by using the rail top centerline point cloud coordinates;

[0102] The first track curvature radius and the corresponding curvature radius variance are calculated as follows:

[0103]

[0104] In the formula, is the first track curvature radius, V is the linear speed, is the angular velocity in radians;

[0105] Based on the curvature radius error propagation formula:

[0106] ,

[0107] Get the error propagation coefficient and , and use the error propagation coefficient to calculate the variance corresponding to the first track curvature radius :

[0108]

[0109] , are the linear velocity and angular velocity variances, respectively.

[0110] The second track curvature radius and the corresponding curvature radius variance are obtained by first weighting the second track curvature radius calculated by fitting the coordinates of the track top centerline point cloud, and then obtaining the curvature radius variance corresponding to the second track curvature radius by inverting the coefficient matrix of the indirect adjustment method equation of the circular curve parameters. .

[0111] The target curvature radius is optimized and solved by using the first track curvature radius and the corresponding curvature radius variance and the second track curvature radius and the corresponding curvature radius variance.

[0112] The target curvature radius is solved according to the following formula:

[0113]

[0114] In this formula,R 0 is the target curvature radius, is the first track curvature radius and the corresponding curvature radius variance, is the radius of curvature of the second track and the corresponding variance of the curvature radius.

[0115] The target curvature radius is substituted into the circular curve fitting formula as a priori linear parameter of the rail, and the spatial position of the rail top center line is determined by performing overall constraint adjustment on the rail top center line.

[0116] S500, combines the geometric design parameters of the rail section and the coordinates of the centerline of the rail top to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage. The key point here does not refer to a specific point. According to the calculation requirements, any point on the track section can be used as a key point, usually the center point of the rail top, a point 16mm below the rail top for measuring the track gauge, etc.

[0117] Specifically, the step includes:

[0118] Establish a rail section coordinate system, with the midpoint of the line connecting the midpoints of the left and right rail tops at the target mileage as the origin of the coordinate system, the X-axis points to the midpoint of the right rail top, the vertical direction is the Y-axis, pointing to the sky as positive, and the Z-axis points to the forward direction to form a right-hand rectangular coordinate system with the X and Y axes;

[0119] Construct the first coordinate transformation matrix from the rail measuring equipment coordinate system to the navigation coordinate system And the second coordinate transformation matrix from the rail section coordinate system to the rail measuring equipment coordinate system ;

[0120] According to the geometric design parameters of the rail section, based on the origin of the rail section coordinate system and the first coordinate transformation matrix and the second coordinate transformation matrix, the geodetic coordinates of any key point of the rail section are calculated;

[0121] S i The coordinates of the center points of the left and right rail tops at the mileage , , the geodetic coordinates of the origin of the rail section coordinate system for:

[0122] ,

[0123] The geodetic coordinates of key points in the rail section model are calculated as follows:

[0124] .

[0125] and Represents the cross-section coordinates at mileage i.

[0126] If the target mileage is located on a circular curve segment, the heading angle at the target mileage is calculated using the following formula: , Pitch angle , Roll Angle :

[0127] ,

[0128] If the target mileage is located on a transition curve, the heading angle at the target mileage is calculated using the following formula: , Pitch angle , Roll Angle :

[0129]

[0130] In the formula, S i Indicates the mileage value at the target mileage. S 0. S t They represent the starting mileage value and the ending mileage value of the track segment where the target mileage is located. , , are the heading angle, pitch angle, and roll angle of the starting point of the track segment where the target mileage is located. , , They are respectively the heading angle, pitch angle, and roll angle of the end point of the track segment where the target mileage is located.

[0131] like Figure 2 As shown, an embodiment of the present invention further provides a device for constructing a three-dimensional geometric shape of a rail space, comprising:

[0132] A data acquisition module, which acquires the motion state information of the rail measuring device and the laser scanning data collected by the rail measuring device; the motion state information includes angular velocity and linear velocity;

[0133] A model building module, which builds a three-dimensional point cloud model of the rail according to the laser scanning data and extracts the midpoint of the top of the rail section in the model;

[0134] A track segmentation module, which determines the rail design line shape change point based on the motion state information of the rail measuring device, and performs track line shape segmentation according to the line shape change point; the track line shape includes a straight line, a transition curve and a circular curve;

[0135] The rail top centerline generation and optimization module performs rail top centerline parameter fitting according to the curve equation corresponding to the track line shape to generate the rail top centerline, and uses the angular velocity and linear velocity information to jointly determine the track line shape information to optimize the spatial position of the rail top centerline;

[0136] The calculation module combines the geometric design parameters of the rail section and the coordinates of the centerline of the rail top to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage.

[0137] See also Figure 3 , Figure 3 Schematic diagram of an electronic device provided by an embodiment of the present invention. Figure 3 As shown, an embodiment of the present invention provides an electronic device 500, including a memory 510, a processor 520, and a computer program 511 stored in the memory 510 and executable on the processor 520. When the processor 520 executes the computer program 511, the following steps are implemented:

[0138] S100, acquiring motion state information of a rail measuring device and laser scanning data collected by the rail measuring device; the motion state information includes an angular velocity and a linear velocity;

[0139] S200, establishing a three-dimensional point cloud model of the rail according to the laser scanning data and extracting the midpoint of the top of the rail section in the model;

[0140] S300, determining a rail design linear change point based on the motion state information of the rail measuring device, and segmenting the rail linear shape according to the linear change point; the rail linear shape includes a straight line, a transition curve and a circular curve;

[0141] S400, performing rail top centerline parameter fitting according to a curve equation corresponding to the track line shape to generate the rail top centerline, and optimizing the spatial position of the rail top centerline using the angular velocity and linear velocity information;

[0142] S500 combines the geometric design parameters of the rail section and the optimized rail top centerline coordinates to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and construct the three-dimensional geometric shape of the rail space.

[0143] See also Figure 4 , Figure 4 A schematic diagram of an embodiment of a computer-readable storage medium provided in an embodiment of the present invention. Figure 4 As shown, this embodiment provides a computer-readable storage medium 600, on which a computer program 611 is stored. When the computer program 611 is executed by a processor, the following steps are implemented:

[0144] S100, acquiring motion state information of a rail measuring device and laser scanning data collected by the rail measuring device; the motion state information includes an angular velocity and a linear velocity;

[0145] S200, establishing a three-dimensional point cloud model of the rail according to the laser scanning data and extracting the midpoint of the top of the rail section in the model;

[0146] S300, determining a rail design linear change point based on the motion state information of the rail measuring device, and segmenting the rail linear shape according to the linear change point; the rail linear shape includes a straight line, a transition curve and a circular curve;

[0147] S400, performing rail top centerline parameter fitting according to a curve equation corresponding to the track line shape to generate the rail top centerline, and optimizing the spatial position of the rail top centerline using the angular velocity and linear velocity information;

[0148] S500 combines the geometric design parameters of the rail section and the optimized rail top centerline coordinates to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and construct the three-dimensional geometric shape of the rail space.

[0149] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0150] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0151] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0152] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1A function specified in one or more boxes.

[0153] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0154] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0155] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for constructing a three-dimensional geometric shape of a rail space, characterized in that: include: Acquire motion state information of the rail measuring device and laser scanning data collected by the rail measuring device; the motion state information includes angular velocity and linear velocity; Establishing a three-dimensional point cloud model of the rail according to the laser scanning data and extracting the midpoint of the top of the rail section in the model; Determine the rail design linear change point based on the motion state information of the rail measuring device, and segment the rail linear shape according to the linear change point; the rail linear shape includes a straight line, a transition curve and a circular curve; Fitting the rail top centerline parameters according to the curve equation corresponding to the track line shape to generate the rail top centerline, and optimizing the spatial position of the rail top centerline using the angular velocity and linear velocity information; Combine the rail section geometry design parameters and the optimized rail top centerline coordinates to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and construct the three-dimensional geometry of the rail space; Utilizing the angular velocity and linear velocity information, optimizing the rail top centerline spatial position includes: Obtain the angular velocity and linear velocity data of the rail measuring equipment at the target mileage, as well as the midline point cloud coordinates of the fitted point cloud; The first track curvature radius and the corresponding curvature radius variance are calculated by using the angular velocity and linear velocity data of the rail measuring equipment, and the second track curvature radius and the corresponding curvature radius variance are calculated by using the fitting rail top centerline point cloud coordinates; Optimizing and solving the curvature radius at the target mileage by using the first track curvature radius and the corresponding curvature radius variance and the second track curvature radius and the corresponding curvature radius variance; The curvature radius at the target mileage is substituted into the circular curve or transition curve formula as a priori linear parameter of the rail, and the rail top centerline is subjected to overall constraint adjustment to determine the spatial position of the rail top centerline of the circular curve segment or transition curve segment.

2. The method according to claim 1, characterized in that The method comprises: determining a rail design linear change point based on the motion state information of the rail measuring device, and performing track linear segmentation according to the linear change point, including: Extracting the position information of the rail measuring equipment from the motion state information; If the heading angle is constant and the roll angle is 0, it is judged that the rail measuring device is located in the straight section of the track; If the heading angle changes constantly and the roll angle is constant and not 0, it is judged that the rail measuring device is located in the circular curve section of the track; If the heading angle change speed increases and the absolute value of the roll angle gradually increases, it is judged that the rail measuring equipment is located in the transition curve section from the straight track section to the circular curve section; If the changing speed of the heading angle decreases and the absolute value of the roll angle gradually decreases, it is judged that the rail measuring equipment is located in the transition curve section from the circular curve section to the straight section of the track.

3. The method according to claim 1, characterized in that: The rail top centerline parameters are fitted according to the curve equation corresponding to the track line shape to generate the rail top centerline, including: The straight line segment linear formula and the circular curve fitting adjustment solution basic relationship are used to fit the straight line segment and the circular curve segment track centerline respectively; Based on the track centerline parameters of the adjacent straight and circular curve segments before and after the transition curve segment, the parameters are determined according to the linear law of the transition curve to generate the track centerline of the transition curve segment.

4. The method according to claim 1, characterized in that: The curvature radius at the target mileage is calculated according to the following formula: In the formula, R 0 is the curvature radius at the target mileage, is the first track curvature radius and the corresponding curvature radius variance, is the radius of curvature of the second track and the corresponding variance of the curvature radius.

5. The method according to claim 1, characterized in that: The first track curvature radius and the corresponding curvature radius variance are calculated using the angular velocity and linear velocity data of the rail measuring equipment. The calculation method is as follows: In the formula, is the first track curvature radius, V is the linear speed, is the angular velocity in radians; Based on the curvature radius error propagation formula: ， Get the error propagation coefficient and , and use the error propagation coefficient to calculate the variance corresponding to the first track curvature radius : , are the linear velocity variance and angular velocity variance respectively.

6. The method according to claim 1, characterized in that Combine the rail section geometry design parameters and rail top centerline coordinates to calculate the geodetic coordinates of key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, including: Establish a rail section coordinate system, with the midpoint of the line connecting the midpoints of the left and right rail tops at the target mileage as the origin of the coordinate system, the X-axis points to the midpoint of the right rail top, the vertical direction is the Y-axis, pointing to the sky as positive, and the Z-axis points to the forward direction to form a right-hand rectangular coordinate system with the X and Y axes; Constructing a first coordinate conversion matrix from the rail measuring device coordinate system to the navigation coordinate system and a second coordinate conversion matrix from the rail section coordinate system to the rail measuring device coordinate system; According to the geometric design parameters of the rail section, based on the origin of the rail section coordinate system and the first coordinate transformation matrix and the second coordinate transformation matrix, the geodetic coordinates of any key point of the rail section are calculated; If the target mileage is located on a circular curve segment, the heading angle at the target mileage is calculated using the following formula: , Pitch angle , Roll Angle : ， If the target mileage is located on a transition curve, the heading angle at the target mileage is calculated using the following formula: , Pitch angle , Roll Angle : In the formula, S i Indicates the mileage value at the target mileage. S 0. S t They represent the starting mileage value and the ending mileage value of the track segment where the target mileage is located. , , are the heading angle, pitch angle, and roll angle of the starting point of the track segment where the target mileage is located. , , They are respectively the heading angle, pitch angle, and roll angle of the end point of the track segment where the target mileage is located.

7. A device for constructing a three-dimensional geometric shape of a rail space, characterized in that: include: A data acquisition module, which acquires the motion state information of the rail measuring device and the laser scanning data collected by the rail measuring device; the motion state information includes angular velocity and linear velocity; A model building module, which builds a three-dimensional point cloud model of the rail according to the laser scanning data and extracts the midpoint of the top of the rail section in the model; A track segmentation module, which determines the rail design line shape change point based on the motion state information of the rail measuring device, and performs track line shape segmentation according to the line shape change point; the track line shape includes a straight line, a transition curve and a circular curve; The rail top centerline generation and optimization module performs rail top centerline parameter fitting according to the curve equation corresponding to the track line shape to generate the rail top centerline, and optimizes the spatial position of the rail top centerline using the angular velocity and linear velocity information; The calculation module combines the rail section geometry design parameters and the optimized rail top centerline coordinates to calculate the geodetic coordinates of the key points of the track section and the heading angle, pitch angle, and roll angle at the target mileage, and construct the three-dimensional geometry of the rail space; Utilizing the angular velocity and linear velocity information, optimizing the rail top centerline spatial position includes: Obtain the angular velocity and linear velocity data of the rail measuring equipment at the target mileage, as well as the midline point cloud coordinates of the fitted point cloud; The first track curvature radius and the corresponding curvature radius variance are calculated by using the angular velocity and linear velocity data of the rail measuring equipment, and the second track curvature radius and the corresponding curvature radius variance are calculated by using the fitting rail top centerline point cloud coordinates; Optimizing and solving the curvature radius at the target mileage by using the first track curvature radius and the corresponding curvature radius variance and the second track curvature radius and the corresponding curvature radius variance; The curvature radius at the target mileage is substituted into the circular curve or transition curve formula as a priori linear parameter of the rail, and the rail top centerline is subjected to overall constraint adjustment to determine the spatial position of the rail top centerline of the circular curve segment or transition curve segment.

8. An electronic device, characterized in that: include: Memory for storing computer software programs; A processor is used to read and execute the computer software program, thereby implementing a method for constructing a three-dimensional geometric shape of a rail space as described in any one of claims 1-6.

9. A non-transitory computer-readable storage medium, characterized in that: The storage medium stores a computer software program, and when the computer software program is executed by the processor, the method for constructing the three-dimensional geometric shape of the rail space as described in any one of claims 1 to 6 is implemented.

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