Precision measurement and tamping operation method for operating conventional-speed railway without control network

Abstract

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Description

A method for precise measurement and tamping operations on conventional railways without a control network Technical Field

[0001] The present invention relates to the field of railway engineering and digitalization, and in particular to a precise measurement and tamping operation method for an operating conventional railway without a control network. Background Art

[0002] Track precision measurement and tamping involves measuring tracks based on a measurement control network and precision measurement technology, using the results to guide large-scale track maintenance machinery in digital precision tamping operations. While this precise measurement and tamping approach significantly improves the quality of track maintenance, it is a highly systematic process that encompasses multiple essential processes, including the deployment of a measurement control network, precise track measurement, design of alignment plans, and precision tamping operations.

[0003] The measurement and control network, the key infrastructure supporting the precision measurement and tamping operation model, is not installed on all conventional railways. First, a control network is not required for lines operating at speeds below 80 km / h, so low-grade conventional railways basically do not have a measurement and control network. Furthermore, due to the high cost of deploying a measurement and control network, some lines operating at speeds of 120 km / h do not have one either. The lack of a control network prevents the existing precision measurement and tamping operation model from fully functioning, impacting the quality, efficiency, and digitalization of line maintenance and repair. Furthermore, due to the lack of a control network, track inspection instruments can only rely on the "on-site mileage + axle counting positioning" mode, which not only has poor positioning accuracy but also requires marking the rails to provide mileage synchronization points for precision tamping operations, resulting in low operating efficiency.

[0004] Summary of the Invention

[0005] In order to solve the defects in the prior art, the present invention provides a method for precise measurement and precise tamping operations on conventional railways in operation without a control network, so as to improve tamping efficiency and save labor costs.

[0006] To this end, the present invention adopts the following technical solutions:

[0007] A method for precise measurement and precise tamping of conventional railways in operation without a control network comprises the following steps:

[0008] S100, temporary reference station deployment and initial track precision measurement, includes the following sub-steps:

[0009] S110, select a temporary reference point offline:

[0010] Set up offline temporary benchmarks at equal intervals within the scope of precise measurement and tamping of skylights. The ground elevation angle of the offline temporary benchmarks is ≥10°. The distance between the offline temporary benchmarks and the track is greater than 10m and they avoid electromagnetic interference sources and objects that cause multipath effects.

[0011] S120, set up a temporary base station:

[0012] Setting up a temporary reference station at the temporary reference point within the initial precision measurement operation area, and collecting raw data through the temporary reference station;

[0013] S130, initial track precision measurement:

[0014] Setting a track detector on the track line to be tamped, using the track detector to synchronously observe data with the temporary reference station to obtain initial track coordinate data;

[0015] S200, office data processing, includes the following steps:

[0016] S210, temporary reference station coordinate solution: using the original data collected in S120, the latitude and longitude coordinates and geoid height of the temporary reference station are obtained by precise point positioning (PPP) technology;

[0017] S220, integrated navigation solution: using the initial track coordinate data obtained in S130, first determine the attitude angle of the track inspection instrument, then perform double difference dynamic post-processing PPK solution on the original data and the initial track coordinate data, and finally use Kalman filtering for reverse smoothing to finally obtain the longitude and latitude coordinates of the track line and the track elevation;

[0018] S230, track elevation fitting: fitting the track elevation obtained in S220 by a "remove-fit-restore" method to obtain the normal height of the track line;

[0019] S240, Track Modeling and Optimization Scheme Design: Use the longitude and latitude coordinates of the track obtained in S220 and the normal height of the track obtained in S230 to design and determine the tamping operation plan;

[0020] S300, tamping operation and precision measurement, includes the following steps:

[0021] S310, performing tamping operation preparation, including:

[0022] S311, installing a tamping vehicle positioning device on the tamping vehicle;

[0023] S312, installing the track inspection instrument on the rail in the short mileage direction of the tamping vehicle;

[0024] S313, setting up the temporary reference station on the temporary reference point within the fine tamping area of ​​the tamping operation;

[0025] S320, tamping vehicle configuration, importing the tamping operation plan determined in S240 into the tamping vehicle control system;

[0026] S330: Tamping operation begins. The track inspection instrument follows the tamping vehicle to perform synchronous track precision measurement after the tamping operation. The longitude and latitude coordinates and normal height of the track after the tamping operation are obtained by the calculation method of steps S220 and S230 until the tamping operation is completed.

[0027] The tamping vehicle locator is used to obtain the current mileage of the tamping vehicle in real time through the temporary reference station.

[0028] Preferably, the interval between the temporary reference points determined in S110 is 5 km.

[0029] Preferably, the distance between the offline temporary reference point in S110 and the electromagnetic interference source and the ground object causing the multipath effect is ≥200m.

[0030] Preferably, the maximum horizontal altitude angle of the offline temporary reference point in S110 is 25°.

[0031] The raw data in S120 includes RINEX format observation value files and RINEX broadcast ephemeris files.

[0032] Preferably, S240 includes the following sub-steps:

[0033] S241, orbital 3D reconstruction:

[0034] Generate a three-dimensional track model using the track gauge, the longitude and latitude coordinates of the track line obtained in S220, the attitude angle of the track inspection instrument, and the normal height of the track line obtained in S230;

[0035] S242, target linear design;

[0036] S243, smoothness optimization adjustment;

[0037] S244, Review and evaluation of tamping operation plans;

[0038] S245, determine the tamping operation plan.

[0039] The longitude and latitude coordinates of the track line described in S241 include the track centerline coordinates, left track coordinates, and right track coordinates with a spacing of 0.15 meters; the track inspection instrument attitude angle includes roll angle, heading angle, and pitch angle; the track gauge is calculated through the longitude and latitude coordinates of the track line.

[0040] When the track to be modeled has track alignment data, the three-dimensional track model in S241 also includes track deviation, track height, and track gauge deviation.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. Track precision measurement: Due to the use of a temporary reference station and track inspection instrument, the present invention can adopt the "GNSS + inertial navigation" positioning mode, with a positioning accuracy of 2cm, no error accumulation, and no need to mark the rails, greatly improving the efficiency of track precision measurement;

[0043] 2. Alignment scheme design: Existing track inspection instruments can only collect internal track geometry parameters (track direction, height, gauge, level, and triangular pits) for scheme design, but cannot measure track alignment (the three-dimensional coordinates of the line centerline), which is not conducive to alignment optimization and alignment scheme design. This method can measure the absolute alignment of the track, and through alignment optimization and fitting, the alignment scheme design is more accurate and scientific.

[0044] 3. Precision tamping operation: In the prior art, the tamping vehicle can only locate its mileage by manually aligning it with the mileage synchronization points marked by the track inspection instrument, which has poor performance, low efficiency, and low degree of digitization. The present invention can integrate a tamping vehicle locator on the tamping vehicle. The tamping vehicle locator can rely on a temporary reference station to obtain the current mileage of the tamping vehicle in real time with an accuracy of 2cm. It can also automatically synchronize with the on-site mileage, reducing labor and improving the precision tamping performance, efficiency and digitization level. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] FIG1 is a flow chart of the method of the present invention;

[0046] Figure 2 is a schematic diagram of the operation process;

[0047] FIG3 is a comparison diagram of the effects before and after the precise measurement and precise tamping operation using the existing method without a control network;

[0048] FIG4 is a comparison diagram of the effects before and after the precise measurement and precise tamping operation using the method of the present invention without a control net;

[0049] In the picture:

[0050] 1. Offline temporary reference station; 2. Track inspection instrument; 3. Vehicle-mounted mobile station; 4. Tamping vehicle; 5. Tamping vehicle locator. DETAILED DESCRIPTION

[0051] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0052] A method for precise measurement and tamping operations on conventional railways operating without a control network utilizes precise point positioning (PPP) to deploy an offline temporary reference station 1 beneath the railway line to be operated. During track precision measurement, the offline temporary reference station serves as a reference station, working in conjunction with a vehicle-mounted rover 3 on a track gauge 2 to obtain precise coordinates of the track line through dynamic post-processing solution (PPK) technology. During precise tamping operations, particularly when a tamping vehicle 4 equipped with a tamping vehicle positioner 5 is used, the offline temporary reference station serves as a primary reference station, providing the tamping vehicle with real-time centimeter-level dynamic mileage positioning services, guiding the tamping vehicle's precise operation, and ultimately improving the efficiency of tamping operations on conventional railways.

[0053] The method includes the following steps, as shown in Figure 1:

[0054] S100, temporary reference station deployment and initial track precision measurement, including:

[0055] S110, select a temporary reference point offline:

[0056] Unlike the 15km spacing set by traditional CORS stations, the precision measurement and tamping system has a one-day operating window of 4-5km, so the spacing of offline temporary reference points is set at 5km. The offline temporary reference point environment should ensure a ground elevation angle of at least 10° to ensure satellite signal visibility (in complex geographical environments or where visibility is obstructed, the elevation angle can be adjusted to 25°). In addition, the distance between the offline temporary reference point and the track should be ≥10m, and the distance from electromagnetic interference sources and ground objects that may cause multipath effects should be ≥200m.

[0057] A temporary offline benchmark point is selected at a suitable location every 5 km along the track to be tamped.

[0058] S120, set up a temporary base station:

[0059] Based on the precise measurement area for the day, select a corresponding temporary reference point from the offline temporary reference points determined by S110 and bury the tripod. Install the temporary reference station on the tripod, ensuring it is centered and leveled. Record the height of the temporary reference station, configure and begin collecting raw data, including RINEX format observation files and RINEX broadcast ephemeris files.

[0060] S130, on-line initial track precision measurement operation: After the temporary reference station has stably collected data, the track is precisely measured online using a track inspection instrument equipped with a vehicle-mounted rover, odometer, and inertial navigation system. The temporary reference station and the vehicle-mounted rover are synchronized in time to obtain the initial track coordinate data.

[0061] Unlike the traditional "blind tamping" method, there is no need to manually paint the mileage synchronization points during the operation. After the measurement operation is completed, the temporary base station will be closed.

[0062] S200, office data processing, includes the following steps:

[0063] S210, temporary base station coordinate solution:

[0064] The deployment of a conventional track control network requires measuring the relative relationship between GNSS measuring stations, that is, relative positioning, so as to deduce the absolute coordinates of each point. This baseline solution method can eliminate common errors between measuring stations, has a simple model, and can achieve accuracy up to the millimeter level.

[0065] However, for the temporary reference station setup method of the present invention, there is only one station. Therefore, the coordinates of the temporary reference station can only be obtained through precise point positioning (PPP). Using PPP to solve the coordinates of the temporary reference station includes the following steps:

[0066] S211, input data into the host computer: the input data includes SP3 format precise orbit file, CLK format satellite clock error file, ERP format earth rotation parameter file, ANTEX format antenna phase clock error correction file, BLO format ocean tide load file, DCB format differential code deviation file, etc. The above data files are obtained by existing technology, and the input data also includes the original data obtained in S120;

[0067] S212, data preprocessing: The data in S211 are preprocessed in the host computer, including cycle slip detection, interpolation of satellite orbits and clock errors, calculation of initial values ​​of parameters such as station coordinates and tropospheric delay, as well as calculation of error correction items such as antenna phase center correction, phase wrap correction, and tidal correction;

[0068] S213, parameter estimation: Using the data obtained in S211 and S212, perform an extended Kalman filter (EKF) to estimate the vector to be estimated x, where:

[0069] The vector x to be estimated is:

[0070] Where s represents a temporary reference station; is the temporary base station coordinate; cdt s is the distance error converted using the temporary reference station clock error; Z S is the tropospheric delay in the zenith direction; G N,s , G E,s These are the two horizontal gradient components in the troposphere;

[0071] is the carrier phase ambiguity of the ionospheric elimination combination, and m is the number of satellites.

[0072] The observation vector y is:

[0073] Where, is the carrier phase of each satellite, is the pseudorange observation value of each satellite, wherein the carrier phase of each satellite and the pseudorange observation value of the satellite are calculated from the raw data obtained in S120;

[0074] In the process of Kalman filter estimation, the state vector to be estimated at time k and its covariance matrix P k The observation vector P at this moment can be used k y k To estimate, as shown in formula (3), formula (4) and formula (5):

[0075] Among them, (-) and (+) are used to distinguish before and after EKF update; K is the gain filter matrix; hx is the observation matrix; R k is the measurement error covariance matrix; H(x) is the partial derivative matrix:

[0076] Where: D is as shown in formula (7), E is as shown in formula (8), M is as shown in formula (9), and element 1 in formula (6) is in matrix form, as shown in formula (10), specifically:

[0077] In formula (9), M W is the mapping function of the tropospheric wet delay in the zenith direction, El and Az are the altitude and azimuth angles of the satellite at the temporary reference station, is the unit vector from the temporary base station to the satellite.

[0078] The state vector to be estimated and the covariance matrix P k The update of is expressed as formula (11) and formula (12), which is:

[0079] In formula (11) and formula (12), is the system noise transfer matrix from time k to time k+1; is the system noise covariance matrix from time k to time k+1.

[0080] S214, output result: The final output result of the Kalman filter in S213 is the coordinates of the temporary reference station in the International Terrestrial Reference Frame (ITRF) (B 临 L 临 H 临), B 临 and L 临 is the longitude and latitude of the temporary reference station, H 临 is the geodetic height of the temporary reference station. In addition, the output results also include coordinate covariance, temporary reference station clock error, ambiguity and other parameters.

[0081] Years of research and development have enabled Precise Point Positioning (PPP) to achieve a level of accuracy comparable to traditional relative positioning techniques. PPP directly provides highly accurate station coordinates consistent with the International Terrestrial Reference Frame (ITRF). Furthermore, during orbital precision measurement operations, the time required for PPP to achieve high-precision convergence is sufficient.

[0082] S220, integrated navigation solution:

[0083] This process mainly involves solving the data collected in S120 to obtain accurate orbit coordinate data. The integrated navigation solution process includes the following steps:

[0084] S221, inertial navigation solution:

[0085] Inertial navigation solution includes initial alignment and inertial navigation mechanical arrangement. The initial orbit coordinate data obtained by S130 is used to calculate the attitude angle of the track detector by sensitively calculating the earth's rotation and gravity in a stationary state. The calculation method is shown in formula (13):

[0086] Where n represents the navigation coordinate system, b represents the track inspection instrument coordinate system, e represents the Earth-centered Earth-fixed coordinate system, and i represents the inertial coordinate system. is the direction cosine matrix of the attitude angle between the track inspection instrument coordinate system and the navigation coordinate system, which can be converted into three attitude Euler angles, γ n is the projection matrix of gravity in the navigation coordinate system, is the projection matrix of the earth's rotation angular velocity in the navigation coordinate system, γ b is the accelerometer output matrix, is the gyroscope output matrix.

[0087] S222, GNSS data PPK solution:

[0088] Using the GNSS carrier phase measurements from the synchronously observed temporary reference station and the vehicle-mounted rover, a double-difference kinematic post-processing (PPK) solution is performed to obtain a centimeter-level relative position coordinate sequence between the track inspection instrument and the temporary reference station. The relative position coordinate sequence includes the track relative position coordinates and track elevation.

[0089] S223, Kalman filtering and inverse smoothing;

[0090] The GNSS / INS integrated navigation solution adopts a loosely coupled architecture and uses the Kalman filter to achieve high-precision fusion positioning. The Kalman filter state parameters are composed of 21 INS error states and an odometer error proportional factor. The longitude and latitude coordinates z of the Kalman filter track are obtained by subtracting the position calculated by the INS in S221 and the orbit relative position coordinates obtained by the Beidou PPK solution in S222, and are obtained by formula (14):

[0091] in, is the direction cosine matrix of the attitude angle between the Earth-centered Earth-fixed coordinate system and the navigation coordinate system, is the vector from the inertial navigation center to the Beidou antenna phase center in the track detector coordinate system, is the inertial navigation center coordinate in the earth-centered earth-fixed coordinate system obtained by the inertial navigation, is the track relative position coordinate between the track inspection instrument and the temporary reference station obtained in S222.

[0092] Finally, the longitude and latitude coordinates of the track line are obtained.

[0093] S230, track elevation fitting:

[0094] The track elevation obtained through S222 is based on the geoid height of an idealized reference ellipsoid and cannot reflect the actual changes in track elevation. Therefore, normal height based on the quasi-geoid is commonly used in railway engineering. The difference between normal height and geoid height is called elevation anomaly. In order to accurately convert from geoid height to normal height, a "remove-fit-restore" method is used to establish an elevation anomaly residual model for the work area, ultimately obtaining the normal track elevation. This step includes the following sub-steps:

[0095] S231, elevation anomaly decomposition:

[0096] Because the gravity field is superimposable, the decomposition of the elevation anomaly ζ is shown in formula (15):

[0097] ζ=ζ XGM +ζ SRTM3 +ζ Δ (1)

[0098] ζ XGM is the elevation anomaly of the medium-long wave / medium wave part obtained by the Earth gravity field model XGM2019e, ζ SRTM3 is the shortwave elevation anomaly obtained from the global digital elevation model SRTM3, ζ Δ It is the residual between the elevation anomaly calculated by the model and the actual elevation anomaly.

[0099] S232, calculate the Earth's gravity field model value:

[0100] The calculation of elevation anomaly based on the Earth gravity field model XGM2019e uses the following formula:

[0101] Where GM is the gravitational constant of the Earth, β is the radius from the center of the Earth, g is the normal gravity value, N is the highest order of the gravity field model expansion, α is the major radius of the reference ellipsoid, L and B are the longitude and latitude of the Earth respectively, and C is the maximum value of the gravity field model expansion. nt and S nt is the fully normalized bit coefficient, P nt (sinB) is the fully normalized Legendre associative function, n and t are the degree and order of the spherical harmonics, respectively.

[0102] S233, calculate terrain correction value:

[0103] The calculation method of the terrain correction value of all points in the global digital elevation model SRTM3 is shown in formula (17):

[0104] where δ1, δ2, δ3, and δ4 are the terrain corrections at the four grid points of the flow unit, dx and dy are the coordinate differences between the measured point and the grid point in the lower left corner of the flow unit in the X-axis direction and the Y-axis direction, respectively, and D represents the side length of the flow unit.

[0105] S234, calculate normal height:

[0106] Since conventional lines lack elevation benchmarks, it is impossible to obtain the residual between the elevation anomaly calculated by the model and the actual elevation anomaly. Therefore, this residual value can be regarded as 0, that is, ζ Δ = 0. Based on this, the normal height calculation formula of the track line is shown in formula (18):

[0107] H 正常高 =H 大地高 -ζ XGM -ζ SRTM3 (18)

[0108] Where H 正常高 H is the normal height of a point on the track after calibration. 大地高 It is the elevation of a certain point on the track line obtained in S222.

[0109] S240, Track Modeling and Optimization Design, includes the following sub-steps:

[0110] S241, orbital 3D reconstruction:

[0111] The three-dimensional track model is generated using the track line longitude and latitude coordinates, attitude Euler angles, track gauge obtained in S220 and the track line normal height obtained in S230. The track line longitude and latitude coordinates include: track centerline coordinates, left track coordinates, and right track coordinates with equal spacing (usually 0.15 meters); attitude Euler angles include roll angle, heading angle, and pitch angle; and track gauge is calculated using the track line longitude and latitude coordinates. When track line shape data is available, track deviation, track height, track gauge deviation, level and other parameters are calculated;

[0112] S242, Target Linear Design:

[0113] The target horizontal and longitudinal alignments are designed based on the survey data and constraints. The design alignment is based on the principle of minimizing deviation and meeting the alignment requirements of the specification. Since the track elevation is a relative value, the elevation starting point of the longitudinal alignment design can be the geodetic height in plain areas and the normal height in mountainous and hilly areas.

[0114] S243, smoothness optimization adjustment:

[0115] The smoothness optimization and adjustment function mainly optimizes the track lifting and shifting data based on the deviation calculated from the designed target alignment. The data meets the track smoothness requirements and the track lifting and shifting limit requirements. The correction plan can effectively reduce track irregularities.

[0116] S244, Review and evaluation of tamping operation plan:

[0117] According to regulatory requirements, track curve parameters, longitudinal slope length and rate, target speed, and other indicators are reviewed and non-compliant design solutions are automatically avoided during the optimization process.

[0118] Evaluate the scheme according to the China Railway Design and Construction Corporation standard "Guidelines for Optimization and Evaluation of Longitudinal Sections for Precision Measurement and Tamping of Operating Conventional Railway Tracks," comprehensively evaluate and score the target alignment and rectification scheme; and automatically calculate the static TQI based on the measurement data.

[0119] S245, determine the tamping operation plan.

[0120] S300, tamping operation and precision measurement, includes the following steps:

[0121] S310, performing tinkering preparation, as shown in FIG2 , includes:

[0122] S311, installing a tamping vehicle positioning device on the tamping vehicle;

[0123] S312, installing a track detector on the rail in the opposite direction of the tamping vehicle, with the track detector moving in the same direction as the tamping vehicle;

[0124] S313, set up a temporary base station again:

[0125] First, locate the offline temporary benchmark point determined in S110 based on the tamping area for the day's tamping operation and set up a temporary benchmark station at that location. This benchmark station has a dual function: on the one hand, it can serve as a master station, providing differential correction information to the tamping vehicle, thereby achieving precise positioning to guide the operation process; on the other hand, it can also serve as a reference station for the track inspection instrument to evaluate the effectiveness of the tamping operation.

[0126] S320, tamping vehicle configuration:

[0127] Import the tamping plan determined in S245 into the tamping vehicle control system. Specifically, import the Ver data of the track adjustment information in the tamping plan into the tamping vehicle control system, and simultaneously import the XML data of the line information in the tamping plan into the tamping vehicle locator system. Then, perform data initialization and mileage synchronization, and configure the operation information parameters according to the tamping plan. The tamping vehicle locator can obtain the current mileage of the tamping vehicle in real time from the temporary reference station with an accuracy of 2cm, and can also automatically synchronize with the on-site mileage.

[0128] S330, start tamping operation and conduct synchronous track precision measurement:

[0129] The tamping operation begins. The tamping process continues continuously without stopping at the synchronization point. Simultaneously, the track inspection instrument follows the tamping vehicle to perform post-tamping track precision measurement. Using the calculation methods in steps S220 and S230, the latitude and longitude coordinates and normal height of the track after the tamping operation are obtained until the tamping operation is completed.

[0130] The evaluation of tamping effectiveness generally focuses on the improvement rate of the track geometry quality index (TQI). This involves calculating the standard deviation of seven track geometry irregularities within a unit section: horizontal, left height difference, right height difference, left track direction, right track direction, triangular pit, and track gauge. There are two evaluation methods: static improvement rate evaluation and dynamic improvement rate evaluation. The static TQI evaluation focuses on the physical and geometric characteristics of the track, while the dynamic TQI evaluation focuses on the track performance during train operation. The ultimate goal of these two evaluation methods is to comprehensively evaluate the effectiveness of the operation plan and its specific improvement effect on improving track smoothness.

[0131] The longitude and latitude coordinates and normal height of the track line after the tamping operation obtained in S330 of the method of the present invention can be used to calculate the dynamic TQI value and the static TQI value, which are used to evaluate the effect of the tamping operation.

[0132] FIG3 and FIG4 are effect diagrams of precise measurement and precise tamping operations on an operating conventional railway using the existing method and the method of the present invention, respectively, without a control network. It can be seen from the figures that the tamping effect of the method of the present invention is significantly better than that of the prior art.

Claims

1. A method for precise measurement and precise tamping operation of an operating ordinary speed railway without a control network, characterized in that, It includes the following steps: S100, Layout of temporary reference stations and initial precise measurement of tracks, including the following sub-steps: S110, Select offline temporary reference points: Set offline temporary reference points equidistantly within the scope of the precise measurement and tamping skylight operation. The horizontal height angle of the offline temporary reference points ≥ 10°, and the distance between the offline temporary reference points and the track is greater than 10m, avoiding electromagnetic interference sources and ground objects causing multipath effects; S120, Set up temporary reference stations: Set up temporary reference stations on the temporary reference points within the initial precise measurement operation area, and collect raw data through the temporary reference stations; S130, Initial precise measurement operation of tracks: Set up track inspection instruments on the track line to be tamped, and use the track inspection instruments to synchronously observe data with the temporary reference stations to obtain initial track coordinate data; S200, Inward data processing, including the following sub-steps: S210, Solve the coordinates of the temporary reference station: Use the raw data collected in S120 to obtain the longitude, latitude coordinates and geodetic height of the temporary reference station through the precise point positioning PPP technology; S220, Integrated navigation solution: Use the initial track coordinate data obtained in S130. First, determine the attitude angle of the track inspection instrument, then perform double-difference dynamic post-processing PPK solution on the raw data and the initial track coordinate data, and finally use Kalman filtering for backward smoothing to finally obtain the longitude, latitude coordinates and track elevation of the track line; S230, Track elevation fitting: Fit the track elevation obtained in S220 through the "remove - fit - restore" method to obtain the normal height of the track line; S240, Track modeling and optimization scheme design: Use the longitude, latitude coordinates of the track line obtained in S220 and the normal height of the track line obtained in S230 to design and determine the tamping operation scheme; S300, Tamping operation and precise measurement, including the following steps: S310, Prepare for the tamping operation, including: S311, Set up a tamping vehicle locator on the tamping vehicle; S312, Set up the track inspection instrument on the rail in the small mileage direction of the tamping vehicle; S313, Set up the temporary reference station on the temporary reference points within the precise tamping area of the tamping operation; S320, Configure the tamping vehicle, and import the tamping operation scheme determined in S240 into the tamping vehicle control system; S330, Start the tamping operation, and the track inspection instrument follows the tamping vehicle to perform synchronous track precise measurement after the tamping operation, Obtain the longitude, latitude coordinates and normal height of the track line after the tamping operation through the calculation methods in steps S220 and S230 until the tamping is completed; The tamping vehicle locator is used to obtain the current mileage of the tamping vehicle in real time through the temporary reference station.

2. The method for precise measurement and tamping operation of an operating ordinary-speed railway without a control network according to claim 1, wherein: The distance between the temporary reference points determined in S110 is 5km.

3. The method for precise measurement and tamping operation of operating general speed railways without control network according to claim 1, wherein: The distance between the offline temporary reference points in S110 and the electromagnetic interference sources and ground objects causing multipath effects ≥ 200m.

4. The method for precise measurement and tamping operation of operating general speed railways without control network according to claim 1, wherein: The maximum horizon altitude angle of the offline temporary reference point described in S110 is 25°.

5. The method for precise measurement and tamping operation of an operating ordinary speed railway without a control network according to claim 1, characterized in that: The original data described in S120 includes RINEX format observation value files and RINEX broadcast ephemeris files.

6. The method for precise measurement and tamping operation of an operating ordinary speed railway without a control network according to claim 1, characterized in that: S240 includes the following sub-steps: S241, three-dimensional reconstruction of the track: Generate a three-dimensional track model using the gauge, the longitude and latitude coordinates of the track line obtained in S220, the attitude angle of the track inspection instrument, and the normal height of the track line obtained in S230; S242, target alignment design; S243, smoothness optimization adjustment; S244, review and evaluation of the tamping operation plan; S245, determine the tamping operation plan.

7. The method for precise measurement and tamping operation of an operating ordinary-speed railway without a control network according to claim 6, wherein: The longitude and latitude coordinates of the track line described in S241 include the coordinates of the track center line, the left rail coordinates, and the right rail coordinates with a spacing of 0.15 meters; the attitude angle of the track inspection instrument includes the roll angle, the heading angle, and the pitch angle; the gauge is calculated from the longitude and latitude coordinates of the track line.

8. The method for precise measurement and tamping operation of an operating general speed railway without a control network according to claim 6, characterized in that: When the track to be modeled has track alignment data, the three-dimensional track model described in S241 further includes the deviation amount of the track, the alignment and elevation, and the gauge deviation.