Railway line profile measurement method and measurement system

Abstract

The present application relates to a kind of track alignment survey method and measuring system, track alignment survey method includes the following steps, first by inertial navigation system obtains the offset angle of bogie frame, according to the offset angle obtains the displacement of each sampling point of bogie frame in predetermined direction, calculate the displacement of each sampling point of bogie frame relative to track, and further obtain the geometric irregularity state change of steel rail.The present application utilizes inertial navigation technology digital and digital laser sensing technology, provides a kind of high-precision, can realize real-time dynamic detection non-contact track alignment identification method.Inertial navigation technology obtains vehicle running posture, digital laser sensing technology obtains rail profile and generates three-dimensional image, by spatial coordinate change relationship analysis track geometric irregularity state change, realize the purpose of track alignment identification, quickly master the rail state of whole line.

Description

Technical Field

[0001] This invention relates to the field of track inspection technology, specifically to a method and system for measuring track alignment. Background Technology

[0002] With the rapid development of my country's rail transit industry, railway capacity and usage frequency are constantly increasing. Coupled with the influence of the natural environment, roadbed deformation and changes in track geometry seriously affect train operation quality and safety. Therefore, regular rail profile inspection and maintenance are essential. Track alignment identification is the foundation and prerequisite for the detection and analysis of track geometry, and it is of great significance for guiding track maintenance and ensuring train operation safety.

[0003] Traditional track inspection methods are static, relying on manual measurement or specialized lightweight inspection trolleys, which suffer from large errors and low efficiency. Dynamic inspection is the future direction of track inspection technology, and a high-precision dynamic measurement method for track is urgently needed. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for measuring the shape of a track line, which can identify the shape of the track line and quickly grasp the condition of the rails of the entire line.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for measuring the shape of a track line, comprising the following steps:

[0006] Obtain the offset angle of the steering frame;

[0007] The displacement of each sampling point of the steering frame in a predetermined direction is obtained based on the offset angle;

[0008] Calculate the displacement of the bogie frame relative to the track at each sampling point;

[0009] Obtain the changes in the geometric irregularities of the rail.

[0010] As a preferred option, the track alignment measurement method is used for track alignment identification, and includes the following steps:

[0011] Step 1: Obtain the yaw angle γ of the bogie frame through the inertial navigation system. The yaw angle γ is the rotation angle along the z-axis.

[0012] Step 2: Based on the yaw angle γ, obtain the absolute lateral displacement distance of each sampling point of the steering frame as follows:

[0013] Δy b =sinγ·(dx+y x );

[0014] In the formula, y x dx represents the longitudinal distance from the measurement point of the inertial navigation system to the center of the structure, and dx represents the speed of the train at each sampling point.

[0015] Step 3: Obtain the displacement Δy0 of each sampling point of the bogie frame relative to the track:

[0016]

[0017] In the formula, y1 and y2 represent the displacement of the left and right rails at each sampling point of the digital laser sensor, respectively;

[0018] Step four, obtain the track irregularity data Δy as follows:

[0019] Δy=∫(Δy b -Δy0)dt;

[0020] dt is the time derivative.

[0021] As a preferred embodiment, the track alignment measurement method is used for identifying the elevation and depression alignment of a track, and includes the following steps:

[0022] Step 1: Obtain the pitch angle β of the bogie frame through the inertial navigation system. The pitch angle β is the rotation angle of the track inspection beam along the y-axis.

[0023] Step 2: Obtain the vertical displacement Δz of the bogie frame based on the pitch angle β. b for:

[0024] Δz b =sinβ·(x b +dx);

[0025] In the formula, x b dx represents the longitudinal distance from the center of the frame to the end of the frame, and dx represents the speed of the train at each sampling point;

[0026] Step 3: Obtain the vertical displacement Δz of the bogie frame relative to the track. l for:

[0027] Δz l =z l -z0;

[0028] In the formula, z0 is the static vertical distance from the end of the frame to the gauge measurement point, z l The measured vertical distance from the end of the frame to the gauge measurement point;

[0029] Step four, obtain the track elevation irregularity data Δz as follows:

[0030] Δz=∫(Δz b -Δz l )dt;

[0031] dt is the time derivative.

[0032] As a preferred embodiment, the inertial navigation system is flush with the end face of the bogie frame and is located at the center of the left and right side beams of the bogie frame.

[0033] As a preferred option, the rail profile is detected to obtain the single cross-sectional profile of the rail, and three-dimensional spatial coordinate inversion is performed to form a continuous three-dimensional rail profile.

[0034] As a preferred option, a digital laser sensor is used to detect the profile of the rail.

[0035] The present invention also provides a track alignment measurement system, including a memory and a processor. The memory stores a computer program executable by the processor, and the processor executes the computer program to implement the track alignment measurement method described in any of the above embodiments.

[0036] Compared with existing technologies, the advantages of this invention are as follows: This solution utilizes inertial navigation technology and digital laser sensing technology to provide a high-precision, real-time, dynamic, non-contact method for track alignment recognition. Inertial navigation technology acquires the vehicle's running attitude, while digital laser sensing technology acquires the rail profile and generates a three-dimensional image. By analyzing the changes in track geometric irregularities through spatial coordinate variations, the purpose of track alignment recognition is achieved, quickly grasping the rail condition of the entire line. The measurement method provided by this invention possesses technical advantages such as high intelligence, high detection accuracy, and high efficiency. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the track measurement device in this invention;

[0038] Figure 2 This is a schematic diagram of the framework in this invention;

[0039] Figure 3 This is a schematic diagram of the rail alignment.

[0040] Figure 4 This is a schematic diagram of the detection results of track irregularities in Embodiment 1 of the present invention;

[0041] Figure 5 This is a schematic diagram of the detection results for uneven surfaces in Embodiment 2 of the present invention;

[0042] Figure 6 This is a schematic diagram of the track alignment measurement system in this invention.

[0043] In the diagram: 1. Track inspection beam; 2. Connecting seat; 3. Digital laser sensor; 4. Inertial navigation system; 5. Data acquisition equipment; 6. Rail; 7. Measurement system; 71. Memory; 72. Processor. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only 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.

[0045] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0046] This invention discloses a method for measuring track alignment based on a track alignment measuring device, which enables real-time, dynamic, and high-precision identification of track alignment, allowing for rapid assessment of the rail condition of the entire track. See also... Figure 1 and Figure 2 The track measurement device includes a track inspection beam 1, and digital laser sensors 3, an inertial navigation system 4, and data acquisition equipment 5 connected to the track inspection beam 1. Specifically, bogies are connected to both ends of the track inspection beam 1. Digital laser sensors 3 are connected to the corresponding ends of the track inspection beam 1 and the rails 6 via connecting seats 2. Considering the measurement range and accuracy requirements of the digital laser sensors 3, the angle θ between the digital laser sensors 3 and the track plane is set to 45–60°. The distance L1 between the laser emission point and the gauge measurement point of the rail 6 is 300–400 mm, and the measurement line width L2 is 195–260 mm. The digital laser sensors 3 are used to detect the profile of the rails 6 and analyze the inner distance of the track. The inertial navigation system 4 is installed flush with the end face of the bogie frame and at the center of the left and right side beams of the frame. It is used to measure the attitude of the bogie frame and the angular changes of the bogie frame during operation. Its central position prevents deviations in the measurement angle caused by structural changes in the track inspection beam 1. The data acquisition equipment 5 is used for data acquisition and transmission.

[0047] The track alignment measurement method provided by this invention uses an inertial navigation system 4 to identify the alignment changes and curvature characteristics of the track line, and combines the profile detected by the digital laser sensor 3 to perform three-dimensional spatial coordinate inversion. Specifically, it first arranges the coordinates of sampling points on the same cross-section to obtain the profile of a single cross-section of the rail 6, and then converts this into the length of the rail 6 based on the laser sampling frequency and vehicle speed, thereby forming the profile state of the entire track line. The method includes the following steps:

[0048] Step 1: The attitude of the bogie frame is measured by the inertial navigation system 4 to obtain the offset angle of the bogie frame during operation;

[0049] Step 2: Obtain the displacement of each sampling point of the bogie frame in the predetermined direction based on the above offset angle;

[0050] Step 3: Calculate the displacement of each sampling point of the bogie frame relative to the track;

[0051] Step 4: Calculate the changes in the geometric irregularities of rail 6.

[0052] Step 5: By shaping the cross-sectional profile of rail 6, a continuous three-dimensional profile of rail 6 is formed.

[0053] The present invention also provides a track alignment measurement system 7, which may include one or more of the following components: a memory 71, a processor 72, and one or more computer programs, wherein the one or more computer programs may be stored in the memory 71 and configured to be executed by one or more processors 72, and the one or more computer programs are configured to perform the aforementioned track alignment measurement method.

[0054] The memory 71 may include random access memory (RAM) or read-only memory (ROM). The memory 71 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 71 may include a program storage area and a data storage area. The program storage area may store instructions for implementing an operating system, instructions for implementing at least one function, instructions for implementing the various method embodiments described below, etc. The data storage area may also store data created by the measurement system 7 during use.

[0055] The processor 72 may include one or more processing cores. The processor 72 connects to various parts of the measurement system 7 using various interfaces and lines, and performs various functions and processes data of the measurement system 7 by running or executing instructions, programs, code sets, or instruction sets stored in the memory 71, and by calling data stored in the memory 71. Optionally, the processor 72 may be implemented using at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 72 may integrate one or a combination of several of the following: a Central Processing Unit (CPU) and a modem. The CPU primarily handles the operating system and applications; the modem is used for wireless communication. It is understood that the modem may also not be integrated into the processor 72 and may be implemented separately using a communication chip.

[0056] To facilitate understanding, the present invention will be further described in detail below with reference to embodiments. It should also be understood that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention shall fall within the scope of protection of the present invention.

[0057] Example 1

[0058] The track alignment measurement method provided in this embodiment is used for track alignment identification. Track alignment usually refers to the lateral unevenness of the gauge point on the inner side of the rail head along the length direction along the track extension direction. It is caused by track laying construction, track maintenance, accumulation of lateral residual strain of the track panel, uneven wear of the rail side, fastener failure, inconsistent lateral elasticity of the track, etc.

[0059] The measurement method includes the following steps:

[0060] Step 1: Obtain the yaw angle γ of the bogie frame through the inertial navigation system 4. The yaw angle γ is the rotation angle along the z-axis.

[0061] Step 2: Based on the yaw angle γ, obtain the absolute lateral displacement distance of each sampling point of the steering frame as follows:

[0062] Δy b =sinγ·(dx+y x )

[0063] In the formula, see Figure 2 y xdx represents the longitudinal distance from the four measurement points of the inertial navigation system to the center of the structure, and dx represents the speed of the train at each sampling point.

[0064] Step 3, obtain the displacement Δy0 of each sampling point of the bogie frame relative to the track:

[0065]

[0066] In the formula, y1 and y2 represent the displacement of the left and right rails 6 at each sampling point of the digital laser sensor 3, respectively;

[0067] Step 4: Obtain the track irregularity data Δy, see [link / reference] Figure 3 and Figure 4 :

[0068] Δy=∫(Δy b -Δy0)dt,

[0069] In the formula, dt is the time derivative.

[0070] Example 2

[0071] The track alignment measurement method provided in this embodiment is used for identifying track elevation and unevenness. Elevation and unevenness are mainly caused by elevation deviations due to track construction, bridge deflection deformation, and residual deformation of the track bed and subgrade. Track elevation irregularities are mainly calculated using the relationship between the pitch angle of the gyroscope in the inertial navigation system 4 and the change in the displacement of the structure.

[0072] The measurement method includes the following steps:

[0073] Step 1: Obtain the pitch angle β of the bogie frame through the inertial navigation system 4. The pitch angle β is the rotation angle of the track inspection beam 1 along the y-axis.

[0074] Step 2: Obtain the vertical displacement Δz of the bogie frame based on the pitch angle β. b (That is, the vertical displacement of track inspection beam 1 along the z-axis) is:

[0075] Δz b =sinβ·(x b +dx)

[0076] In the formula, see Figure 2 x b dx represents the longitudinal distance from the center of the frame to the end of the frame, and dx represents the speed of the train at each sampling point;

[0077] Step 3: Obtain the vertical displacement Δz of the bogie frame relative to the track. l for:

[0078] Δz l =z l -z0

[0079] In the formula, z0 is the static vertical distance from the end of the frame to the gauge measurement point, z l The measured vertical distance from the end of the frame to the gauge measurement point;

[0080] Step four, obtain the track elevation irregularity data Δz as follows:

[0081] Δz=∫(Δz b -Δz l )dt,,where dt is the time derivative, see details Figure 5 .

[0082] This invention provides a high-precision, real-time, dynamic, non-contact method for track alignment recognition, utilizing inertial navigation technology and digital laser sensing technology. Inertial navigation technology acquires the vehicle's running attitude, while digital laser sensing technology acquires the rail profile and generates a 3D image. By analyzing the changes in track geometric irregularities through spatial coordinate variations, the method achieves track alignment recognition and quickly grasps the rail status of the entire track. The measurement method provided by this invention boasts advantages such as high intelligence, high detection accuracy, and high efficiency.

[0083] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for measuring the shape of a track line, characterized in that, Includes the following steps: Obtain the offset angle of the steering frame; The displacement of each sampling point of the steering frame in a predetermined direction is obtained based on the offset angle; Calculate the displacement of the bogie frame relative to the track at each sampling point; Obtain the changes in the geometric irregularities of the rail; The measurement method is used for track alignment identification and specifically includes the following steps: Step 1: Obtain the yaw angle γ of the bogie frame; Step 2: Obtain the absolute lateral displacement Δy of each sampling point of the steering frame based on the yaw angle γ. b for: ； In the formula, y x dx represents the longitudinal distance from the measurement point of the measuring device to the center of the frame, and dx represents the speed of the train at each sampling point. Step 3, obtain the displacement Δy0 of the framework relative to the track at each sampling point: ； In the formula, y1 and y2 represent the displacement of the left and right rails at each sampling point, respectively; Step four, obtain the track irregularity data Δy as follows: ； In the formula, dt is the time derivative.

2. The method for measuring the shape of a track line according to claim 1, characterized in that, It can also be used for identifying the elevation and eccentricity of tracks.

3. The method for measuring the shape of a track line according to claim 2, characterized in that, Includes the following steps: Step 1: Obtain the pitch angle β of the bogie frame; Step 2: Obtain the vertical displacement Δz of the bogie frame based on the pitch angle β. b for: ； In the formula, x b dx represents the longitudinal distance from the center of the frame to the end of the frame, and dx represents the speed of the train at each sampling point; Step 3: Obtain the vertical displacement Δz of the bogie frame relative to the track. l for: Δz l =with l - z0; In the formula, z0 is the static vertical distance from the end of the frame to the gauge measurement point, z l The measured vertical distance from the end of the frame to the gauge measurement point; Step 4: Obtain uneven data for: ； In the formula, dt is the time derivative.

4. The method for measuring the shape of a track line according to claim 1, characterized in that, The bogie frame offset angle is measured using an inertial navigation system.

5. The method for measuring the shape of a track line according to claim 4, characterized in that, The inertial navigation system is flush with the end face of the bogie frame and is located at the center of the left and right side beams of the bogie frame.

6. The method for measuring the shape of a track line according to claim 1, characterized in that, It also includes the following steps: The rail profile is inspected, and the inspected profile is combined with three-dimensional spatial coordinate inversion to form a continuous three-dimensional rail profile.

7. The method for measuring the shape of a track line according to claim 6, characterized in that, The profile of the rail is detected using a digital laser sensor.

8. A track alignment measurement system, characterized in that, It includes a memory and a processor, the memory storing a computer program executable by the processor, the processor executing the computer program to implement the track alignment measurement method according to any one of claims 1-7.

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