A rack segment train position correction method and device

Abstract

The present application relates to the technical field of rail transit, in particular to a rack section train position correction method and device. The rack section train position correction device comprises: encoding modules symmetrically arranged on both sides of the rack and a vehicle-mounted detection module installed below the train bogie. The encoding module is configured with an encoding area for identifying the line position, and the encoding information on the encoding area is symmetrically distributed. The present application uses the eddy current induction of the vehicle-mounted detection module and the encoding module to read the line position when the train passes through the encoding module, so as to correct the train position. The present application only needs to install the encoding module on the track, without the need for additional construction of ground machine rooms, communication facilities and other supporting equipment. Moreover, the vehicle-mounted detection module can read the line position through the eddy current induction of the vehicle-mounted detection module and the encoding module only when the vehicle-mounted detection module is working normally, so the probability of being disturbed by environmental factors is extremely low, and the present application is easy to implement.

Description

Technical Field

[0001] This invention relates to the field of rail transit technology, and in particular to a method and apparatus for correcting the position of a train on a rack rail section. Background Technology

[0002] Precise absolute positioning and correction of the train are the core prerequisites for ensuring driving safety, achieving automatic train operation (ATO), precise stopping, and safety protection.

[0003] In the field of rail transit, there are currently two main methods for positioning trains. One is relative positioning based on onboard sensors such as odometers and inertial measurement units (IMUs), which calculates the train's position through integration. However, this method is susceptible to factors such as wheel-rail slippage, gear wear, and gear-rail meshing clearance, and the positioning error accumulates with the mileage, making it impossible to achieve long-term accurate positioning. To solve the positioning error of the first method, a second method of absolute position positioning correction has been added. This method is based on external reference devices such as trackside transponders or beacons. The onboard equipment obtains the absolute position by reading the signals from these trackside devices, thereby correcting its own accumulated error.

[0004] For rack railways, which are different from conventional railways, racks (i.e., racks) are installed between the two rails. It is often impossible to install transponders or beacons used by ordinary trains. Existing technology usually corrects the position of the train in the rack railway section by setting external reference equipment such as permanent magnet coded sleepers.

[0005] For example, Chinese Patent CN114889676B discloses a method, device, and system for correcting the position of a rack train. The technical solution includes: receiving wheelset pulse signals from a counting head group; obtaining train information from a region controller based on the head group sequence number; reading the current train's wheelset count from a pre-stored train parameter table based on the vehicle identification number; when the received pulse signal count from the counting head group matches the current train's wheelset count, reading the corresponding head's mileage information from a pre-stored head information table; generating absolute position correction information based on the read mileage information and the vehicle identification number; and sending the absolute position correction information to the region controller, so that the region controller sends the absolute position correction information to the corresponding train based on the vehicle identification number.

[0006] However, this technical solution requires the installation of a large number of counting magnetic heads along the entire rail spacing, as well as the construction of ground equipment rooms and communication lines, resulting in a large amount of supporting equipment. Furthermore, the necessary conditions for the normal operation of this technical solution include: the ground magnetic heads being intact, the vehicle-to-ground wireless communication being unimpeded, and the area controller being operating normally. If any of these components fails, the positioning will fail, and train correction will not be possible. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of existing geared rail section train position correction technology, such as the large number of supporting equipment and operating conditions, and to provide a geared rail section train position correction method and device.

[0008] In a first aspect, the present invention provides a train position correction device for a rack rail section. The rack rail section train position correction device includes: coded modules symmetrically arranged on both sides of the rack rail and an on-board detection module installed below the train bogie. The coded modules symmetrically arranged on both sides of the rack rail are used to identify the track position. One side of each coded module contacts the rack rail, and the other side is designated as a coded area. The coded area includes several coded segments, and the several coded segments are symmetrically distributed on the coded area. Each coded segment includes: a starting coded segment, a position coded segment, and an ending coded segment. The starting coded segment is located at both ends of the coded area, the ending coded segment is located in the middle of the coded area, and the position coded segment is located between the starting coded segment and the ending coded segment. The on-board detection module installed below the train bogie is used to read the track position through eddy current sensing between the on-board detection module and the coded module when the train passes the coded modules, thereby correcting the train position.

[0009] According to a preferred embodiment, the encoding region is divided into several encoding units. The encoding region performs binary encoding by varying the presence or absence of gaps in the encoding units.

[0010] According to a preferred embodiment, the encoding module is made of metal. The vehicle-mounted detection module employs an eddy current sensor. The vehicle-mounted detection module acquires undulating eddy current sensing signals as the signal passes through the encoding module.

[0011] According to a preferred embodiment, the geared track section train position correction device further includes an on-board processing module electrically connected to the on-board detection module. The on-board processing module acquires the eddy current induction signal and converts the eddy current induction signal into a digital signal.

[0012] According to a preferred embodiment, the on-board processing module reads a preset mapping table of line location codes and line kilometer markers, and queries the mapping table based on the digital signal to identify the current line location of the train.

[0013] According to a preferred embodiment, the on-board processing module converts the eddy current induction signal into a digital signal in the following manner:

[0014] Envelope correction is performed on the eddy current induction signal; The eddy current induction signal is standardized using a linear interpolation up / down sampling method; The standardized eddy current induction signal is sampled at equal intervals, and the signal intensity at each sampling point is compared with a threshold Q. ’ Compare and generate binary codes.

[0015] According to a preferred embodiment, the rack-and-pinion train position correction device further includes a storage module electrically connected to the on-board processing module. The storage module is used to store a mapping table between line position codes and line kilometer markers.

[0016] According to a preferred embodiment, the encoding module is fixedly installed on both sides of the waist of the toothed rail; the encoding module is installed below the teeth of the toothed rail or flush with the bottom of the teeth.

[0017] According to a preferred embodiment, the on-board detection module is installed on at least one side of the train relative to the rack rail.

[0018] The present invention also provides a method for correcting the position of a train on a rack track, which uses a rack track train position correction device provided by the present invention to correct the position of the train.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a train position correction device for a rack rail section. It uses encoding modules on both sides of the rack rail and an on-board detection module installed below the train bogie. When the train passes the encoding modules, the track position is read using eddy current induction between the on-board detection module and the encoding module to correct the train's position. This invention only requires the installation of encoding modules on the track, eliminating the need for additional ground equipment rooms, communication facilities, or other supporting equipment. Furthermore, the track position can be read using eddy current induction between the on-board detection module and the encoding module as long as the on-board detection module is functioning normally. The probability of interference from environmental factors is extremely low, making it easy to implement. Attached Figure Description

[0020] Figure 1 This is a block diagram of the device components of the present invention.

[0021] Figure 2 This is a schematic diagram of the encoding module of the present invention.

[0022] Figure 3 This is a schematic diagram of the installation of the encoding module of the present invention.

[0023] Figure 4 This is a flowchart of the method of the present invention.

[0024] Marked in the image: Encoding module 100; encoding area 110; starting encoding segment 111; position encoding segment 112; ending encoding segment 113; encoding unit 101; bolt 102; mounting base plate 120; vehicle detection module 200; vehicle processing module 300; storage module 400; rack rail 500; tooth 501; vehicle positioning system 600. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0026] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," and "outer," etc., used in the description of specific embodiments of the present invention to indicate orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, and for enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0027] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," "parallel," and "coaxial" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, parallel, or coaxial. Slight tilt or deviation is permissible, as long as it does not affect the normal function of the relevant component. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," not that the structure must be perfectly horizontal; a slight tilt is acceptable. "Coaxial" means that two components are arranged as coaxially as possible, allowing them to move coaxially or approximately coaxially when their relative positions change. Alternatively, it can be simplified to mean that the corresponding device / component / element, when arranged in "horizontal," "vertical," "suspended," "parallel," or "coaxial" directions, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. For example, the deviation in the "coaxial" direction is controlled within 0.2-1mm, preferably within 0.2-0.5mm. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the solution of the present invention.

[0028] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0029] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as two, three, four, five, six, seven, eight, or nine, and can even exceed nine.

[0030] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to connection methods commonly used in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0031] When a rack train is in motion, it determines its current position by counting the number of revolutions of its wheels. However, because the wheels may spin or slip during operation, the actual distance traveled by the train does not match the number of revolutions, resulting in an error between the theoretical and actual positions of the train. To eliminate this error, it is necessary to obtain the accurate position of the train after it has traveled a certain distance and update the train's position, which is called train position correction.

[0032] The method and apparatus for correcting the position of a train on a rack rail section provided by this invention are improvements made to address the shortcomings of existing rack rail section train position correction technologies, such as the large number of supporting equipment and operating conditions.

[0033] Example 1 This embodiment provides a train position correction device for a geared rail section. See also: Figure 1 , Figure 2 and Figure 3 The gear train position correction device includes: an encoding module 100 and an on-board detection module 200 installed under the train bogie.

[0034] The system includes symmetrically arranged coding modules 100 on both sides of the rack rail 500 and an on-board detection module 200 installed under the train bogie. The coding modules 100, symmetrically arranged on both sides of the rack rail 500, are used to identify the track position. One side of each coding module 100 contacts the rack rail 500, and the other side is designated as a coding area 110. The coding area 110 includes several coding segments, which are symmetrically distributed on the coding area 110. Each coding segment includes a starting coding segment 111, a position coding segment 112, and an ending coding segment 113. The starting coding segment 111 is located at both ends of the coding area 110, the ending coding segment 113 is located in the middle of the coding area 110, and the position coding segment 112 is located between the starting and ending coding segments 111 and 113. The on-board detection module 200, installed under the train bogie, is used to read the track position through eddy current sensing between the on-board detection module 200 and the coding module 100 when the train passes the coding module 100, in order to correct the train's position.

[0035] This embodiment provides a train position correction device for a rack rail section. It uses encoding modules 100 on both sides of the rack rail 500 and an on-board detection module 200 installed below the train bogie. When the train passes the encoding modules 100, the track position is read using eddy current induction between the on-board detection module 200 and the encoding module 100 to correct the train position. This invention only requires the installation of the encoding modules 100 on the track, eliminating the need for additional ground equipment rooms, communication facilities, or other supporting equipment. Furthermore, the on-board detection module 200 only needs to be functioning normally to read the track position through eddy current induction between the on-board detection module 200 and the encoding module 100, without considering other influencing factors, making it easy to implement.

[0036] Example 2 This embodiment is a further explanation of Embodiment 1, and repeated content will not be repeated.

[0037] The coding region 110 is divided into several coding units 101. The coding region 110 performs binary encoding by whether or not gaps are opened in the coding units 101.

[0038] Preferably, the encoding module 100 is made of metal. The vehicle-mounted detection module 200 uses an eddy current sensor. The vehicle-mounted detection module 200 acquires undulating eddy current sensing signals after passing through the encoding module 100.

[0039] Preferably, the geared track section train position correction device further includes an on-board processing module 300 electrically connected to the on-board detection module 200. The on-board processing module 300 acquires eddy current induction signals and converts the eddy current induction signals into digital signals.

[0040] Preferably, the on-board processing module 300 reads a preset mapping table of line location codes and line kilometer markers, and queries the mapping table based on digital signals to identify the current line location of the train.

[0041] Preferably, the on-board processing module 300 converts the eddy current induction signal into a digital signal in the following way: Envelope correction is performed on the eddy current induction signal; The eddy current induction signal is standardized by using a linear interpolation up / down sampling method; The standardized eddy current induction signal is sampled at equal intervals, and the signal intensity at each sampling point is compared with a threshold Q. ’ Compare and generate binary codes.

[0042] Preferably, the rack-and-pinion section train position correction device further includes a storage module 400 electrically connected to the on-board processing module 300. The storage module 400 is used to store a mapping table between the line position code and the line kilometer marker.

[0043] Preferably, the encoding module 100 is fixedly installed on both sides of the waist of the toothed rail 500; the encoding module 100 is installed below the teeth of the toothed rail 500 or flush with the bottom of the teeth.

[0044] Preferably, the on-board detection module 200 is installed on at least one side of the train relative to the rack rail 500.

[0045] See Figure 1 The gear train position correction device includes: an encoding module 100, an on-board detection module 200, an on-board processing module 300, and a storage module 400.

[0046] The encoding module 100 is made of metal and is mounted on the gear rail 500.

[0047] The on-board detection module 200, mainly composed of eddy current sensors, is installed under the train bogie.

[0048] When the on-board detection module 200 passes the encoding module 100 as the train travels, the on-board detection module 200 and the encoding module 100 generate eddy current induction, and the on-board detection module 200 will acquire the eddy current induction signal with high and low fluctuations.

[0049] The encoding module 100 is made of metal. See also Figure 2 and Figure 3The encoding module 100 is structured such that one side contacts the toothed rail 500, and the other side is designated as an encoding area 110. The encoding area 110 is provided with a plurality of encoding units 101. The encoding units 101 are evenly spaced on the encoding area 110. Binary encoding is achieved by whether or not gaps are created in the encoding units 101. Preferably, when an encoding unit 101 is left empty, it corresponds to binary code 0; when no gaps are created in the encoding unit 101, it corresponds to binary code 1.

[0050] When the on-board detection module 200 passes the encoding module 100 as the train travels, the encoding area 110 generates eddy current induction with the on-board detection module 200. Since some encoding units 101 are notched and some are made of metal, the on-board detection module 200 will acquire eddy current induction signals with high and low fluctuations.

[0051] See Figure 3 The encoding module 100 includes a mounting base 120. The mounting base 120 is connected to the toothed rail 500 by bolts 102. One side of the mounting base 120 contacts the side wall of the toothed rail 500, and the encoding area 110 is disposed on the other edge of the mounting base 120. The encoding area 110 is perpendicular to the mounting base 120.

[0052] See Figure 2 The coding region 110 includes several coding segments, including: a start coding segment 111, a position coding segment 112, and an end coding segment 113. The position coding segment 112 is located between the start coding segment 111 and the end coding segment 113.

[0053] The starting coding segment 111, the location coding segment 112, and the ending coding segment 113 together constitute a set of codes used to mark the kilometer of the line.

[0054] Preferably, the coding region 110 of the coding module 100 is provided with two sets of symmetrically distributed codes for marking the same line kilometer. Preferably, two starting coding segments 111 are located at both ends of the coding region 110, an ending coding segment 113 is located in the middle of the coding region 110, and a position coding segment 112 is located between the starting coding segment 111 and the ending coding segment 113. The composition of each coding unit 101 in the coding region 110 is symmetrically distributed on the coding region 110.

[0055] Preferably, two sets of symmetrically distributed codes for marking the same line kilometer are provided in the coding area 110, so that the same coding content can be identified when the train passes in both directions. Furthermore, even if an installation error occurs when the coding module 100 is installed, i.e., the coding module 100 is installed backwards, the symmetrical coding module 100 can still be identified normally, thus improving the fault tolerance rate of train position identification.

[0056] The vehicle-mounted processing module 300 is electrically connected to the vehicle-mounted detection module 200 and is used to identify and convert the eddy current induction signals with high and low fluctuations acquired by the vehicle-mounted detection module 200 into digital signals.

[0057] Preferably, the on-board processing module 300 is used to convert the eddy current induction signal with high and low fluctuations acquired by the on-board detection module 200 into a line position code composed of 0 / 1 binary code; and the on-board processing module 300 reads the mapping table between the line position code and the line kilometer marker pre-stored in the storage module 400 according to the converted line position code to determine the current position of the train (i.e., the line kilometer marker). The on-board processing module 300 transmits the current position of the train (i.e., the line kilometer marker) to the on-board positioning system 600 to realize the correction of the train position.

[0058] Storage module 400 is used to store a mapping table between line location codes and line kilometer markers.

[0059] Preferably, the vehicle positioning system 600 is used for real-time positioning monitoring and display, handling of positioning anomaly alarms, trajectory storage and playback tracing, and operation and maintenance management of vehicle positioning equipment. It can display the train's location on the driver's interface and provide location information to other trains.

[0060] See Figure 2 The encoding module 100 is made of corrosion-resistant metal, and the encoding area 110 has multiple notches set according to the encoding rules. When the vehicle detection module 200 passes through the encoding area 110 where there is a metal part, it has a strong eddy current induction; when the vehicle detection module 200 passes through the encoding area 110 where there is no metal part, there is no eddy current induction, thus obtaining a fluctuating eddy current induction signal.

[0061] See Figure 2 The encoding module 100 may include a starting encoding segment 111, a position encoding segment 112, and an ending encoding segment 113. Preferably, the starting encoding segment 111 may be configured with multiple repeated codes for initial position encoding correction, and the ending encoding segment 113 may use a continuous high eddy current induction signal for final position encoding correction. The purpose is to enable the on-board processing module 300 to effectively extract the position encoding segment 112. Simultaneously, the encoding module 100 adopts a symmetrical left-right structure design, which allows for accurate train position encoding to be obtained in both directions of train operation, and also enables comparison and verification of the accuracy of the decoding of the encoded portion.

[0062] See Figure 2 The encoding module 100 can be made of 430 ferritic stainless steel or 420 martensitic stainless steel, or other metals with good corrosion resistance and eddy current properties.

[0063] The encoding format of encoding module 100 can be referenced. Figure 2 Encoding unit 101 contains a metal corresponding to binary "1", and encoding unit 101 does not contain a metal corresponding to binary "2".

[0064] The starting encoding segment 111 is set to "1010" and the ending encoding segment 113 is set to "111". The positional encoding is determined by the line length in terms of the number of bits. For example, if the line length is 40km and the average spacing of encoding modules 100 is 200m, then 200 modules are needed, and an 8-bit binary encoding is sufficient. 8 =256 codes.

[0065] Figure 3 This is a schematic diagram showing the installation of the encoding module 100 and the toothed rail 500. Figure 3 (a) is a top view. Figure 3 (b) is a side view. Figure 3 (c) is the front view.

[0066] See Figure 3 The coding module 100 is installed on both sides of the waist of the rack 500 by welding, bolting 102 or integral molding. After installation, it is flush with or slightly lower than the waist of the rack 500 to avoid interference with other parts of the train.

[0067] The rack of the encoding module 100 is installed on both sides of the waist of the rack 500. It does not intrude into the meshing area of ​​the rack 500, does not change the core meshing parameters of the rack 500 such as tooth pitch and tooth profile, does not affect the normal meshing of the train drive gear and the rack 500, does not reduce the traction transmission efficiency, and is compatible with the drive requirements of existing rack 500 trains.

[0068] like Figure 3 As shown, the coding module 100 is set in two sets at each point, and is fixedly installed on both sides of the waist of the standard toothed rail 500 by bolts 102. The installation position does not intrude into the meshing area of ​​the toothed rail 500, and is installed below the tooth 501 or flush with the bottom of the tooth 501 to avoid interference with the train bogie and other components.

[0069] The on-board detection module 200 is installed under the train bogie. Since the length of the coding module 100 can be flexibly controlled, the on-board detection module 200 can be installed at a suitable position between the rack 500 and the wheel rail. Since the coding module 100 has been installed on both sides of the rack 500, the on-board detection module 200 can be installed on either side of the rack 500. If the reliability is improved, it can also be installed on both sides.

[0070] The on-board detection module 200 is mainly composed of eddy current sensors. The eddy current sensors of the on-board detection module 200 are non-contact eddy current sensors with a detection distance of 5-15mm from the coding area 110. They are resistant to dust, rain, snow, and vibration, and are suitable for the harsh operating environment of the geared rail section.

[0071] The on-board detection module 200 transmits the collected signals to the on-board processing module 300.

[0072] Based on existing rack railway standards and a maximum design speed of V=40km / h, and considering that a single coding unit can collect N=10 data points, to reduce the weight of coding module 100 and minimize the impact of train vibrations on the rack of coding module 100, the total length of coding module 100 should ideally not exceed 1m. (See also...) Figure 2 One encoding module 100 has 30 encoding units 101. The width L of each encoding unit 101 is calculated to be 0.03m. According to the formula N=L f / V, the sampling frequency of the eddy current sensor f=N V / L=10 (40 / 3.6) / 0.03=3704Hz, therefore it is recommended that the sampling frequency of the eddy current sensor be ≥5.12KHz.

[0073] The encoding area 110 of the encoding module 100 adopts a passive mechanical structure, requiring no power supply or electronic components, resulting in high reliability and long service life. The eddy current sensor used in the vehicle-mounted detection module 200 adopts a non-contact design, resulting in less wear and convenient maintenance.

[0074] The encoding area 110 of the encoding module 100 adopts a symmetrical structure design, which can meet the requirements of single-line bidirectional operation and assist in encoding recognition and verification.

[0075] Using this embodiment for train position correction on a rack track does not rely on trackside transponders or other equipment, significantly reducing construction and maintenance costs. It can also work stably in areas without signals, such as tunnels and mountainous regions, avoiding positioning failures caused by trackside equipment damage or signal interference.

[0076] The on-board processing module 300 is installed inside the train and mainly consists of an embedded processor with built-in error compensation, signal filtering, encoding parsing and matching algorithms.

[0077] Error compensation algorithms perform linear interpolation upsampling / downsampling on the signal, converting the entire sampled signal into a standardized point signal, reducing the differences in the number of sampling points caused by the different speeds of the train passing by.

[0078] Signal filtering algorithms filter and amplify signals to eliminate interference signals, obtain the signal envelope, and avoid local abrupt changes affecting the encoding and parsing results.

[0079] The encoding parsing algorithm obtains the corresponding value of the envelope by sampling at equal intervals based on the equal envelope, and identifies the number at that point as 0 / 1.

[0080] The matching algorithm is used to verify the encoding results and match the mapping table, and finally gives the absolute position information of the train.

[0081] The onboard processing module 300 identifies the absolute position information of the train and transmits it to the onboard positioning system 600. The onboard positioning system 600 updates, displays, stores (tracks), and interacts with the train's absolute position information (e.g., providing the signaling system with the train's position information for automatic train control, controlling the train to accelerate / decelerate).

[0082] The storage module 400 is used to pre-store the codes of each encoding module 100 and the corresponding location kilometer markers, and to store the sequential relationship between each code.

[0083] Example 3 This embodiment provides a method for correcting the position of a train on a rack rail section, which uses the rack rail section train position correction device described in Embodiment 1 or Embodiment 2 to correct the position of the train.

[0084] See Figure 4 The present invention provides a method for correcting the position of a train on a toothed track, comprising the following steps: S1. Real-time encoded signal acquisition: Obtain eddy current induction signal X=[X1, X2, ..., X...] n ].

[0085] The on-board detection module 200 reads eddy current induction signals in real time (values ​​obtained in chronological order based on the sampling frequency). When the on-board detection module 200 passes through the encoding module 100, it can read the fluctuating eddy current induction signals, forming a waveform diagram, and the eddy current induction signals collected by the on-board detection module 200 are recorded as X=[X1, X2, ..., X...]. n ].

[0086] S2. Real-time encoded signal processing: A standardized eddy current induction signal X is obtained through error compensation algorithms, signal filtering, and resampling. ’ =[X ’ 1. X ’ 2、...、X ’ n ].

[0087] Preferably, real-time encoded signal processing includes: Envelope correction is applied to the eddy current induction signal, which fluctuates in height, to reduce the impact of local signal fluctuations.

[0088] Since the sampling frequency of the on-board detection module 200 is fixed and the length of the encoding module 100 is fixed, but the speed of the train passing through the encoding module 100 is different, the total time of the train passing through the encoding module 100 is different, which in turn leads to different numbers of sampling points and different lengths of waveforms. Therefore, it is necessary to convert the waveforms into standard length waveforms through standardization processing (to ensure that the number of points in the waveforms is consistent).

[0089] The specific standardization process is as follows: The envelope-corrected eddy current induction signal is then standardized in time. This is achieved by using linear interpolation upsampling / downsampling to expand / compress the acquired eddy current induction signal to a specified number of data points N. The value of N is determined based on a specified standard operating speed V, evaluated using frequency f and the length of the encoder rack L. The formula is: N = L / (V / f) = L The purpose of f / V signal processing is to convert the eddy current induction signals from the train passing through the coded rack at different speeds into standardized induction signal lengths, which can improve the accuracy of coded signal recognition. The acquired real-time coded signal contains two sets of signals, positive and negative. The eddy current induction signal (waveform signal) is standardized so that both sets of signals can be used for subsequent position verification.

[0090] Real-time coded signal processing, through an error compensation algorithm, converts the eddy current induction signal into a standardized signal. Specifically, the eddy current sensor has a sampling frequency of 5.12 kHz, and the encoding module 100 has 30 encoding units 101, each 0.03 m wide. The standard signal is a conventional train rack rail section with a speed limit of 25 km / h. Therefore, the total number of sampling points in the encoding module 100 is N = 0.03. 30 5120 / (25 / 3.6) = 663.5, therefore, 660 points are used as the number of points for the standardized signal. The eddy current induced signal X is compensated to [X1, X2, ..., X] using a linear interpolation up / down sampling method. 660 Then, through signal filtering, the signal envelope is obtained, and then 660 points are sampled again to obtain the standardized eddy current induction signal X. ’ =[X ’ 1. X ’ 2、...、X ’ 660 ].

[0091] S3. Real-time encoded signal recognition: Perform equidistant sampling, compare the signal intensity of the sampling point with the threshold Q', and identify the specific code.

[0092] Specifically, according to the standard operating speed V, the rack unit length l, the coding recognition sampling interval t=V / l, the induced signal strength Q at the corresponding time is read at intervals of 0.5t, 1.5t, 2.5t, ..., (n-0.5)t, an induced signal strength threshold Q' is set, when Q≥Q', the code is recognized as 1, and when Q<Q', the code is recognized as 0.

[0093] When performing real-time coded signal recognition, since the coding module 100 includes 30 coding units 101 and the number of points is 660, each coding unit 101 has 22 sampling points, and 22 is also the number of intervals for signal recognition; Record [X ’ 11 , X ’ 33 , ..., X ’ 11+(i-1) 22 , ..., X ’ 649 , a total of 30 positions of signal strength, and compare them with the threshold Q'; When the signal strength is ≥Q', the code is recognized as 1, and when the signal strength is <Q', the code is recognized as 0, so as to identify the code of the coding module 100, such as the code "1010 10110110 111 111 01101101 0101" in Figure 1 .

[0094] S4. Position matching: Read out the absolute position of the train through the mapping table.

[0095] After the coded content is identified, the preset start coding section 111 and end coding section 113 are cut off, so that the position coding section 112 can be obtained, which is compared with the coding mapping table to obtain the absolute position information of the train.

[0096] For example, when performing position matching, the identified code "1010 10110110 111 111 011011010101" is cut off the start coding section 111 "1010" and the end coding section 113 "111" to obtain the position coding section 112 "10110110", and the mapping table is read from the storage module, so that the current absolute position information of the train can be matched.

[0097] S5. Position verification: First, judge whether the start code and the end code are equal to the preset constants; if equal, perform symmetry verification; if not equal, execute S6. Position correction.

[0098] Symmetric verification is performed by checking whether the two position codes are equal. If they are equal, the matching absolute position of the train is fed back to the on-board positioning system 600 for position correction. If they are not equal, S6, position correction, is executed.

[0099] Preferably, to confirm the accuracy of the location information, the correctness of the starting and ending coding positions needs to be checked first, that is, to identify whether the standard coding value set for this line is loaded; secondly, since the coding module 100 adopts a symmetrical structure design, it is necessary to identify whether the two location coding segments 112 are symmetrical. If both checks are satisfied, the absolute position of the train corresponding to the location code can be output to the vehicle positioning system 600.

[0100] Specifically, location verification includes: First, remove the 4-bit value of the starting encoding segment 111 and the 3-bit value of the ending encoding segment 113, and identify whether they are the constants "1010" and "111" set for this line. If they do not match, it means that the signal recognition is abnormal, the recognition of the position encoding segment 112 is not feasible, and the verification fails. The 15-bit value "111 01101101 0101" after encoding is reverse-identified again to determine whether its start and end codes are the constants "1010" and "111" set for this line. The codes at the two positions are compared to confirm whether they are the same. If they are different, the verification fails. If all verifications pass, the location matching result will be fed back to the vehicle positioning system 600 for location correction. If any check fails, execute S6, position correction.

[0101] S6. Position Correction: Based on the number of a correctly identified coding module 100 on the line and the direction of train travel, the number of the next coding module 100 that is expected to be passed is calculated. The system determines whether the difference between the calculated train position and the relative position of the train is less than a threshold. If it is less, the position matching result is fed back to the vehicle positioning system 600 for position correction. If it is not less, the system indicates that the positioning has failed.

[0102] Position Correction: Since the route planning has been completed after the route design is completed, for routes that run in one direction, the relationship between two consecutive coding modules 100 can be pre-set in the storage module 400. Therefore, after the position verification and identification of the current coding module 100, if the position verification of the previous coding module 100 is successful, and the difference between the real-time relative position of the train and the position of the coding module 100 at this location is within a certain range, the absolute position of the train corresponding to the coding module 100 that is expected to pass through in the storage module 400 can be given to the vehicle positioning system 600.

[0103] Considering the regularity of the line layout of the coding module 100, that is, when the train travels in one direction on a single line, the train will inevitably pass through multiple consecutively identified coding modules 100 one by one. Therefore, when the position verification fails or a non-existent code appears, the number of the next coding module 100 to be passed can be calculated based on the number of the previously correctly identified coding module 100 and the direction of train travel. The relative position of the train in the vehicle positioning system 600 is compared with the train position corresponding to the number of the next coding module 100. If the difference is within a set threshold, such as 10m, the absolute position of the train corresponding to the number of the next coding module 100 can be fed back to the vehicle positioning system 600 as the absolute position of the train detected this time, so as to realize the train position correction.

[0104] In cases of power outages, shutdowns, or restarts of the train, the calculated position cannot be used for correction; the position must be corrected using the absolute positioning method.

[0105] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A train position correction device for a rack rail section, characterized in that, include: The coding modules (100) symmetrically arranged on both sides of the toothed rail (500) are used to identify the line position; The encoding module (100) contacts the toothed rail (500) on one side and is configured as an encoding area (110) on the other side. The coding region (110) includes several coding segments, and the several coding segments are symmetrically distributed on the coding region (110); The coding segment includes: a start coding segment (111), a position coding segment (112), and an end coding segment (113). The starting coding segment (111) is located at both ends of the coding area (110), the ending coding segment (113) is located in the middle of the coding area (110), and the position coding segment (112) is located between the starting coding segment (111) and the ending coding segment (113). An on-board detection module (200) installed under the train bogie is used to read the track position through eddy current induction of the on-board detection module (200) and the encoding module (100) when the train passes the encoding module (100) in order to correct the train position.

2. The geared rail section train position correction device according to claim 1, characterized in that, The coding region (110) is divided into several coding units (101). The encoding region (110) is binary encoded by whether or not a gap is opened in the encoding unit (101).

3. The geared rail section train position correction device according to claim 2, characterized in that, The encoding module (100) is made of metal; the vehicle-mounted detection module (200) uses an eddy current sensor; The vehicle-mounted detection module (200) acquires eddy current sensing signals with high and low fluctuations after passing through the encoding module (100).

4. The geared rail section train position correction device according to claim 3, characterized in that, It also includes an on-board processing module (300) electrically connected to the on-board detection module (200). The on-board processing module (300) acquires the eddy current sensing signal and converts the eddy current sensing signal into a digital signal.

5. A train position correction device for a rack rail section according to claim 4, characterized in that, The on-board processing module (300) reads a preset mapping table of line location codes and line kilometer markers, and queries the mapping table according to the digital signal to identify the current line location of the train.

6. The geared rail section train position correction device according to claim 4, characterized in that, The on-board processing module (300) converts the eddy current induction signal into a digital signal in the following way: Envelope correction is performed on the eddy current induction signal; The eddy current induction signal is standardized using a linear interpolation up / down sampling method; The standardized eddy current induction signal is sampled at equal intervals, and the signal intensity at each sampling point is compared with a threshold Q. ’ Compare and generate binary codes.

7. A train position correction device for a rack rail section according to claim 5 or 6, characterized in that, It also includes a storage module (400) electrically connected to the on-board processing module (300). The storage module (400) is used to store a mapping table between line location codes and line kilometer markers.

8. The geared rail section train position correction device according to claim 1, characterized in that, The encoding module (100) is fixedly installed on both sides of the waist of the toothed rail (500); the encoding module (100) is installed below the teeth of the toothed rail (500) or flush with the bottom of the teeth.

9. A train position correction device for a rack rail section according to claim 1, characterized in that, The on-board detection module (200) is installed on at least one side of the train relative to the rack (500).

10. A method for correcting the position of a train on a rack rail section, characterized in that, The train position is corrected using a geared track section train position correction device as described in any one of claims 1-7.

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