Vehicle position detection device and vehicle position detection method

Abstract

The present invention provides a vehicle position detection device and a vehicle position detection method that can estimate the turning angle of a railway vehicle using a sensor that detects angular velocity. [Solution] The on-board device (vehicle position detection device) 2 comprises a sensor unit (angular velocity detection means) 220 for detecting the angular velocity of the on-board device 2, a railway GIS (map information storage means) 231 for storing map information of multiple railway tracks R, and a position calculation unit (vehicle position calculation means) 241 for calculating which railway track the railway vehicle is located on (either a reference line or a branch line). The position calculation unit 241 acquires information on the angular velocity of the on-board device 2 in the horizontal direction from the sensor unit 220, calculates the distance between the branch point and the railway vehicle in the direction of the reference line, and calculates the perpendicular distance from the reference line to the current position of the railway vehicle based on the angular velocity and distance. It also determines which railway track the railway vehicle is located on based on the distance and perpendicular distance.

Description

Technical Field

[0001] The present invention relates to a vehicle position detection device and a vehicle position detection method for detecting the position of a railway vehicle on a railway track.

Background Art

[0002] In order to prevent accidents such as contact between railway vehicles and workers during railway construction, etc., a train approach warning system is used (for example, see Patent Document 1). In the train approach warning system described in Patent Document 1, the position of a railway vehicle is measured using a GNSS (Global Navigation Satellite System) such as GPS (Global Positioning System), and a railway GIS (Geographic Information System), which is map information including the position information of a railway track, is referred to calculate the position (approximate kilometers) of a railway vehicle running on the railway track. Then, when the railway vehicle approaches a worker within a predetermined distance (warning distance), an alarm is generated on an alarm terminal carried by the worker, and the alarm is stopped when the railway vehicle passes the working position of the worker. Also, while the alarm is being transmitted, the worker retreats to a position away from the railway track.

[0003] Also, when positioning data from GPS satellites cannot be used, such as inside a tunnel, a position detection device for ensuring the safety of a maintenance vehicle for inspecting rails, etc. is used (for example, see Patent Document 2). The position detection device described in Patent Document 2 inputs the distance from a reference line into a neural network when detecting the position of a railway vehicle running in a predetermined area having a plurality of branch lines with respect to the reference line, and outputs the reliability of each line. Then, the track position with the highest reliability is taken as the position of the vehicle itself.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

[0005] Incidentally, conventional train approach warning systems using GNSS can only detect the position of railway vehicles in the direction of the rails (kilometer mile direction), and cannot detect or determine the lateral direction, such as the direction of a branch or whether the train is traveling on the main line or a branch line. This is because the distance error due to GNSS positioning is greater than the lateral distance between tracks.

[0006] Given this background, conventional methods for recognizing lateral direction have involved laying ID (Identification) tags or ground beacons that record location information (kilometers, route, line type, track number, etc.) on the railway tracks, and reading them with receiving devices mounted on the trains. However, this method involves enormous costs for laying ground equipment, installing equipment on the railway vehicles, and maintaining the ground equipment. Furthermore, in the case of methods that utilize neural networks, such as the position detection device described in Patent Document 2, it is necessary to construct the required neural network. This requires optimizing the weight coefficients within the network during the learning process and searching for the optimal number of nodes and layers in the hidden layers, resulting in high time costs. In addition, using a neural network requires performing calculations equal to the product of the number of nodes in the input layer, the number of nodes in the hidden layer, the number of layers in the hidden layer, and the number of nodes in the output layer. This computational load is enormous, requiring a device with high computing power.

[0007] Therefore, the present invention aims to provide a vehicle position detection device and a vehicle position detection method that can estimate the position of a railway vehicle perpendicular to the rails based on a sensor that detects angular velocity, and that can contribute to reducing the cost of the device by reducing the amount of computation. [Means for solving the problem]

[0008] To solve the above-mentioned problems, the vehicle position detection device according to the present invention comprises: an angular velocity detection means for detecting the angular velocity, which indicates the angle of rotational speed in the horizontal direction of a railway vehicle running on the railway track; and a vehicle position calculation means for calculating which railway track the railway vehicle is located on. The vehicle position calculation means acquires the angular velocity of the railway vehicle detected by the angular velocity detection means near the branching point between a reference line on the railway track and a branch line branching off from the reference line; calculates the distance from the branching point to the current position of the railway vehicle in the direction of the reference line; calculates the perpendicular distance from the reference line to the current position of the railway vehicle based on the acquired angular velocity of the railway vehicle and the calculated distance of the railway vehicle in the direction of the reference line; and determines which railway track the railway vehicle is located on based on the calculated distance of the railway vehicle in the direction of the reference line and the calculated perpendicular distance to the current position of the railway vehicle.

[0009] The vehicle position detection device according to this invention may include a map information storage means that stores map information including the latitude and longitude of each point on a plurality of railway tracks, and when the vehicle position calculation means detects, based on the map information, that the railway vehicle is approaching the branching point between a reference line on the railway track and a branch line branching off from the reference line, it may acquire the angular velocity of the railway vehicle detected by the angular velocity detection means.

[0010] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means repeatedly performs the following processes at predetermined intervals: acquiring the angular velocity of the railway vehicle, calculating the distance of the railway vehicle in the direction of the reference line, calculating the perpendicular distance to the current position of the railway vehicle, and determining which railway track the railway vehicle is located on.

[0011] The vehicle position detection device according to this invention may also be configured such that the vehicle position calculation means calculates an angular velocity integral value by integrating the acquired angular velocity of the railway vehicle over time, and calculates the distance in the direction of the reference line from the branching point to the current position of the railway vehicle based on the angular velocity integral value.

[0012] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means calculates the perpendicular distance to the current position of the railway vehicle multiple times within a predetermined time, stores the maximum and minimum values ​​of the perpendicular distance to the current position of the railway vehicle, and determines which railway track the railway vehicle is located on based on the calculated maximum and minimum values ​​of the perpendicular distance to the current position of the railway vehicle.

[0013] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means determines that the railway vehicle is located on a branch line when the maximum or minimum value of the perpendicular distance to the current position of the calculated railway vehicle reaches a threshold value determined for each branch line.

[0014] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means determines that it is impossible to determine if the calculated maximum or minimum perpendicular distance to the current position of the railway vehicle reaches a threshold value determined for each branch line and is outside a predetermined range.

[0015] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means determines that the railway vehicle is located on the reference line when the calculated distance of the railway vehicle in the direction of the reference line reaches a threshold value determined for each reference line.

[0016] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means determines that it is impossible to determine if the calculated distance of the railway vehicle in the direction of the reference line reaches a threshold value determined for each reference line and is outside a predetermined range.

[0017] The vehicle position detection device according to this invention may also be configured to provide a predetermined notification if the position of the railway vehicle cannot be determined.

[0018] The vehicle position detection device according to this invention may also be configured such that the vehicle position calculation means calculates the distance in the direction of the reference line from the branching point to the current position of the railway vehicle based on the map information.

[0019] The vehicle position detection device according to this invention may be configured such that the vehicle position calculation means calculates the distance in the direction of the reference line from the branching point to the current position of the railway vehicle based on the moving speed of the railway vehicle detected by the speed detection means provided in the railway vehicle for detecting the moving speed of the railway vehicle.

[0020] The vehicle position detection device according to this invention may be configured such that when the vehicle position calculation means determines that the railway vehicle has passed a specific branching point and is located on the branching line, it corrects the position of the railway vehicle based on the position of the branching point, the distance in the direction of the reference line from the branching point to the current position of the railway vehicle, and the perpendicular distance to the current position of the railway vehicle.

[0021] The vehicle position detection method according to this invention is a vehicle position detection method to be executed by a computer comprising a processor and a storage unit, wherein the storage unit stores map information including the latitude and longitude of each point on a plurality of railway tracks, and the processor performs an angular velocity detection step in which it detects the angular velocity indicating the angle of rotational speed in the horizontal direction of a railway vehicle running on the railway track, and a vehicle position calculation step in which it calculates which railway track the railway vehicle is located on, and in the vehicle position calculation step, based on the map information, the railway vehicle is located at the branching point between a reference line on the railway track and a branch line branching off from the reference line The system is characterized by detecting that both vehicles are approaching, obtaining the angular velocity of the railway vehicle detected in the angular velocity detection step, calculating the distance from the branching point to the current position of the railway vehicle in the direction of the reference line, calculating the perpendicular distance from the reference line to the current position of the railway vehicle based on the obtained angular velocity of the railway vehicle and the calculated distance of the railway vehicle in the direction of the reference line, and determining which railway track the railway vehicle is located on based on the calculated distance of the railway vehicle in the direction of the reference line and the calculated perpendicular distance to the current position of the railway vehicle. [Effects of the Invention]

[0022] According to the vehicle position detection device and vehicle position detection method of this invention, the angular velocity, which indicates the angle of rotational speed in the horizontal direction of a railway vehicle running on a railway track, is detected, and the perpendicular distance from the reference line to the current position of the railway vehicle is calculated based on the angular velocity and the distance of the railway vehicle in the direction of the reference line, and the location of the railway track on which the railway vehicle is located is determined based on that distance. Therefore, compared to methods such as GNSS positioning, it is possible to detect the location of the railway vehicle on which railway track it is located without being affected by lateral position errors with respect to the direction of travel of the railway vehicle. Furthermore, compared to methods using neural networks, the amount of computation is reduced, which can contribute to reducing the cost of the device.

[0023] According to the vehicle position detection device of the present invention, the angular velocity of the acquired railway vehicle is time-integrated to calculate an angular velocity integrated value, the relative angle of the traveling direction of the self-device with respect to the object is calculated, and the distance in the direction of the reference line from the branch point to the current position of the railway vehicle is calculated. Therefore, by reducing the amount of calculation, it is possible to contribute to cost reduction of the device.

[0024] According to the vehicle position detection device of the present invention, the maximum value and the minimum value of the perpendicular distance to the current position of the railway vehicle are held, and based on the calculated maximum value and the minimum value of the perpendicular distance to the current position of the railway vehicle, it is determined on which railway track the railway vehicle is located. Therefore, it is possible to perform a more accurate position determination on the railway track.

[0025] According to the vehicle position detection device of the present invention, when the maximum value or the minimum value of the perpendicular distance to the current position of the railway vehicle reaches a threshold value determined for each branch line, it is determined that the railway vehicle is located on the branch line. Further, when the distance in the direction of the reference line of the railway vehicle reaches a threshold value determined for each reference line, it is determined that the railway vehicle is located on the reference line. Here, since the threshold value can be set based on various laws, regulations, and standards, the work related to the setting becomes easy. Therefore, it is possible to contribute to cost reduction of the threshold value setting.

[0026] According to the vehicle position detection device of the present invention, based on the map information, the distance in the direction of the reference line from the branch point to the current position of the railway vehicle is calculated. Further, based on the moving speed of the railway vehicle detected by the speed detection means provided in the railway vehicle, the distance in the direction of the reference line from the branch point to the current position of the railway vehicle is calculated. Therefore, it is possible to realize a more accurate determination process.

[0027] According to the vehicle position detection device of this invention, when it is determined that a railway vehicle has passed a specific junction and is located on a junction line, the position of the railway vehicle is corrected based on the position of the junction, the distance from the junction to the current position of the railway vehicle in the direction of a reference line, and the perpendicular distance to the current position of the railway vehicle. As a result, cumulatively accumulated errors in the position of the railway vehicle can be automatically removed, and the accuracy of the estimation of the position of the railway vehicle (kilometer marker accuracy) can be improved. Furthermore, by improving kilometer marker accuracy, in a vehicle approach warning system using kilometer markers, the time that workers must evacuate from their work positions to allow a railway vehicle to pass can be reduced, thereby improving work efficiency. [Brief explanation of the drawing]

[0028] [Figure 1] This is a schematic diagram showing a vehicle approach warning system 1 according to Embodiment 1 of the present invention. [Figure 2] Figure 1 is a schematic block diagram showing the on-board device 2. [Figure 3] Figure 2 shows the calculation concept of the position calculation unit 241 in the on-board device 2. [Figure 4] Figure 2 is a flowchart showing the calculation procedure of the position calculation unit 241 in the on-board device 2. [Figure 5] This flowchart shows the calculation procedure for the branching decision process in the flowchart in Figure 4. [Figure 6] This is a schematic diagram showing a vehicle approach warning system 1A according to Embodiment 2 of the present invention. [Figure 7] This is a schematic diagram showing a vehicle approach warning system 1B according to Embodiment 3 of the present invention. [Figure 8] This is a flowchart showing the calculation procedure of the position calculation unit 241 in the on-board device 2 according to Embodiment 4 of the present invention. [Modes for carrying out the invention]

[0029] The present invention will be described below based on the illustrated embodiments. The following description and drawings are illustrative examples for illustrating the present invention, and have been omitted and simplified as appropriate for clarity of explanation. The present invention can also be carried out in various other forms. Unless otherwise specified, each component may be singular or plural. In the following description, identical components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated.

[0030] (Embodiment 1) <1. Configuration of Vehicle Approach Warning System 1> Figure 1 is a schematic diagram showing a vehicle approach warning system 1 according to Embodiment 1, which uses the vehicle position detection device and vehicle position detection method of the present invention. This vehicle approach warning system 1 comprises an on-board device (vehicle position detection device) 2 mounted on a railway vehicle Tr, a warning terminal 3 carried by a worker W engaged in railway construction, and a server device 4, all of which are connected to each other so as to be able to communicate via a communication network NW. Here, the communication network NW is, for example, a mobile phone network or the internet.

[0031] The onboard device 2 is mounted on the railway vehicle Tr and, as described later, detects the position of the railway vehicle Tr on the railway track R (for example, the kilometer marker indicating the distance from the starting point set for each railway line), and also detects which railway track R the railway vehicle Tr is located on, and transmits train information including these detection results to the server device 4. Specifically, when the railway vehicle Tr passes the branching point between the reference line R1 and the branch line R2 that branches off from the reference line R1 on the railway track R shown in Figure 1, the onboard device 2 detects whether the railway vehicle Tr is located on the reference line R1 or the branch line R2, and transmits the detection result to the server device 4.

[0032] The alarm terminal 3 has the following functions: to receive GNSS signals (e.g., GPS signals) from GNSS satellites (e.g., positioning satellites such as GPS satellites) and to detect the position of the alarm terminal 3, i.e., the position of worker W, based on the received GNSS signals; to receive train information of the railway vehicle Tr from the server device 4; to generate an alarm using sound, light, etc., when the position of the railway vehicle Tr approaches within alarm distance from the position of worker W; and to stop the alarm when the position of the railway vehicle Tr passes the position of worker W.

[0033] Here, the alarm terminal 3 can detect and input the railway track R (work route) on which worker W is working, and the train information from the onboard device 2 includes which railway track R the railway vehicle Tr is located on (either the base line R1 or the branch line R2). Therefore, an alarm is generated when the position of the railway vehicle Tr approaches within the alarm distance from the position of worker W, and the railway track R on which the railway vehicle Tr is traveling is the same as the railway track R on which worker W is working. The alarm generation function also includes a function that displays the approach distance and speed of the railway vehicle Tr in text information, or displays icons of the work position and the railway vehicle Tr on the track diagram so that the positional relationship can be intuitively understood.

[0034] As described above, in this embodiment, the alarm terminal 3 makes the decision to generate and stop the alarm, but this may be done by the server device 4. In this case, the server device 4 collects train information from the onboard device 2 and worker information (information including the location of worker W, work route, line type, etc., where the location may be in kilometers or latitude and longitude) from the alarm terminal 3. Then, when a railway vehicle Tr approaches worker W within the alarm distance and they are on the same railway track R, the server device 4 sends an alarm signal to the alarm terminal 3 to generate an alarm, and when the railway vehicle Tr passes worker W, the server device 4 sends an alarm stop signal to the alarm terminal 3 to stop the alarm.

[0035] Figure 2 is a schematic block diagram showing the on-board device 2 of Figure 1. The on-board device 2 comprises a communication unit 210, a sensor unit (angular velocity detection means) 220, a storage unit 230, and a control unit 240. As shown in Figure 2, the communication unit 210, sensor unit 220, storage unit 230, and control unit 240 are electrically connected by a bus or the like.

[0036] The communication unit 210 is a communication interface for communicating with the server device 4 via a communication network NW, either wired or wirelessly. Any communication protocol can be used as long as communication between the two devices is possible. This communication unit 210 communicates using communication protocols such as TCP / IP or the USB standard.

[0037] The sensor unit 220 is a sensor for detecting the angle (angular velocity) of the horizontal rotational speed of the on-board device 2 (railway vehicle Tr), and is a device that outputs speed information of the on-board device 2 (railway vehicle Tr). The sensor unit 220 may be composed of, for example, a gyro sensor, an acceleration sensor, etc.

[0038] The memory unit 230 stores programs for executing various control processes and functions within the control unit 240, input data, etc., and consists of memory including RAM, ROM, etc., and storage including HDD, SSD, flash memory, etc. The memory unit 230 stores the railway GIS (map information storage means) 231. The memory unit 230 also temporarily stores data that has been communicated with the server device 4.

[0039] Railway GIS231 is a geographic information system that stores map information, including the latitude and longitude of each point on multiple railway tracks R. In other words, it is a database that records map information for each railway track R, as well as information on the latitude, longitude, and distance in kilometers for each railway track R. Specifically, for each railway track R, identification information for identifying multiple points (track coordinates) on the railway track R, the latitude and longitude of each point (including junctions), and the distance in kilometers from the starting point of the railway track R (in other words, the starting station) to each point are stored in association with the map information of the railway track R.

[0040] The control unit 240 is realized when the processor constituting the control unit 240 reads a program stored in the memory unit 230 and executes the instructions contained in the program. The control unit 240 controls the operation of the on-board device 2. By operating according to the program, the control unit 240 performs the function of a position calculation unit (vehicle position calculation means) 241.

[0041] The position calculation unit 241 is programming software that calculates which railway track R the railway vehicle Tr is located on (either the base line R1 or the branch line R2). First, the calculation concept will be explained based on Figure 3. In this embodiment, the case where the base line R1, which is the reference railway track, branches into two railway tracks, the branch line R1 and the branch line R2, at a branching point will be mainly explained, but it is similarly applicable to cases where it branches into three or more lines.

[0042] Figure 3 is a diagram illustrating the calculation concept of the position calculation unit 241 in the on-board device 2 shown in Figure 2. The railway vehicle Tr shown in Figure 3 travels on the railway track R and, by comparing its current position with the railway GIS 231, detects that it is approaching and passing the branching point M0 between the reference line R1 and the branch line R2 that branches off from the reference line R1. Alternatively, the control unit 240 may detect that the railway vehicle Tr is approaching the branching point M0 when it is located at a predetermined distance from the branching point M0. Then, the position calculation unit 241 acquires information on the angle of rotational speed in the horizontal direction of the on-board device 2 (railway vehicle Tr), i.e., angular velocity, from the sensor unit 220. The position calculation unit 241 then integrates the acquired angular velocity over time to calculate the angular velocity integral value θ. The angular velocity integral value θ represents the rotation angle in the horizontal direction of the on-board device 2 (railway vehicle Tr).

[0043] The position calculation unit 241 calculates the distance d from the branching point M0 to the current position of the railway vehicle Tr in the direction of the reference line R1. Figure 3 shows the distance d when the railway vehicle Tr is located at point P1 when it is located on the branching line R2, and at point P2 when it is located on the reference line R1. At this time, the position calculation unit 241 may calculate the distance d by comparing the current position of the railway vehicle Tr with the railway GIS 231, or it may calculate the distance d based on the moving speed of the railway vehicle Tr detected by a speed detection means, so-called speedometer, that the railway vehicle Tr is equipped with to detect the moving speed of the railway vehicle Tr.

[0044] The position calculation unit 241 calculates the perpendicular distance f from the reference line R1 to the current position of the railway vehicle Tr based on the angular velocity integral value θ (rotation angle) and the distance d of the railway vehicle Tr in the direction of the reference line R1. Figure 3 shows the perpendicular distance f when the railway vehicle Tr is located at point P1 when it is located on the branch line R2. At this time, the position calculation unit 241 may calculate the perpendicular distance f multiple times within a predetermined time or while the railway vehicle Tr is located at a predetermined distance from the branch point M0, and each time it calculates the maximum value f1 and minimum value f2 of the perpendicular distance f to the current position of the railway vehicle Tr, it may store these values ​​and calculate the maximum value f1 and minimum value f2 of the perpendicular distance f to the current position of the railway vehicle Tr.

[0045] In this case, the perpendicular distance f and its maximum value f1 and minimum value f2 are given by the following formulas.

number

[0046] The position calculation unit 241 then determines, based on the calculated distance d and the calculated perpendicular distance f, which railway track the railway vehicle Tr is located on, that is, whether it is located on the base line R1 or the branch line R2. At this time, the determination may also be based on either the maximum value f1 or the minimum value f2 of the perpendicular distance. For example, the position calculation unit 241 may determine that the railway vehicle Tr is located on the branch line R2 when the maximum value f1 or the minimum value f2 of the perpendicular distance reaches a threshold value determined for each branch line R2. For example, if the dashed line L1 shown in Figure 3 is set as this threshold, and the railway vehicle Tr passes through the intersection P3 of the dashed line L1 and the branch line R2, the maximum value f1 or the minimum value f2 of the perpendicular distance exceeds the perpendicular distance f at the intersection P3, so it is determined that the railway vehicle Tr is located on the branch line R2. The reason for determining based on either the maximum value f1 or the minimum value f2 of the perpendicular distance is that the sign of the perpendicular distance f changes depending on the rotation direction of the railway vehicle Tr.

[0047] Furthermore, the position calculation unit 241 may determine that the railway vehicle Tr is located on the reference line R1 when, for example, the distance d of the railway vehicle Tr in the direction of the reference line R1 reaches a threshold value determined for each reference line R1. For example, this threshold value may be set as the dashed line L2 shown in Figure 3, and when the railway vehicle Tr passes through the intersection P4 of the dashed line L2 and the reference line R1, the distance d exceeds the distance d at the intersection P4, so it is determined that the railway vehicle Tr is located on the reference line R1.

[0048] In other words, the position calculation unit 241 determines, for example, that if the railway vehicle Tr is located in the branch line angle area A1 shown in Figure 3, the railway vehicle Tr is located in the branch line R2, and if it is located in the reference line angle area A2, the railway vehicle Tr is located in the reference line R1. The position calculation unit 241 determines that the position is undeterminable or abnormal if the railway vehicle Tr is located in the other area A3 shown in Figure 3. The position calculation unit 241 may also determine that the position is undeterminable or abnormal if the maximum value f1 or minimum value f2 of the perpendicular distance reaches the above threshold and the railway vehicle is located in the other area A3, or if the distance d reaches the above threshold and the railway vehicle is located in the other area A3. Furthermore, if the position is undeterminable or abnormal, the unit may provide a predetermined notification to the user. This allows the user to recognize the abnormality and take appropriate action, such as stopping the vehicle or manually setting its position.

[0049] <2. Operation of Vehicle Approach Warning System 1> Next, we will explain specific calculation methods based on these calculation concepts using the flowcharts shown in Figures 4 and 5.

[0050] Figure 4 is a flowchart showing the calculation procedure of the position calculation unit 241 in the on-board device 2 of Figure 2. First, the current position of the railway vehicle Tr is obtained (step S1), and compared with the map information (information of each point and junction) of the railway GIS 231 (step S2). Then, it is determined whether or not the railway vehicle Tr is approaching a junction on the railway track R (vehicle position calculation step, step S3). If the railway vehicle Tr is not approaching a junction on the railway track R (if "N" is obtained in step S3), the process returns to step S1 and the same process is repeated.

[0051] On the other hand, if the railway vehicle Tr approaches a junction on the railway track R (if the result is "Y" in step S3), a junction determination process is performed to determine which railway track R the railway vehicle Tr is located on (step S4). Once the junction determination process is completed and the track on which the vehicle is located is determined (step S5), the process returns to step S1 and the same process is repeated. Here, the distance used to determine whether or not the railway vehicle Tr has approached a junction is predetermined according to the surrounding environment and environmental elements for each junction, which will be described later.

[0052] Next, we will explain the branching determination process shown in step S4.

[0053] Figure 5 is a flowchart showing the calculation procedure for the branching determination process in the flowchart of Figure 4. First, as described above, information on the angle of rotational speed in the horizontal direction of the on-board device 2 (railway vehicle Tr), i.e., angular velocity, is obtained from the sensor unit 220 (angular velocity detection step and vehicle position calculation step, step S41), and the obtained angular velocity is integrated over time to calculate the angular velocity integral value θ, i.e., the rotation angle in the horizontal direction of the on-board device 2 (railway vehicle Tr) (vehicle position calculation step, step S42).

[0054] Next, the distance d from the branching point M0 to the current position of the railway vehicle Tr in the direction of the reference line R1 is calculated (vehicle position calculation step, step S43). At this time, in step S43, the distance d may be calculated based on the result of matching the current position of the railway vehicle Tr with the railway GIS231, or the distance d may be calculated based on the moving speed of the railway vehicle Tr detected by a speed detection means, so-called speedometer, that the railway vehicle Tr is equipped with for detecting the moving speed of the railway vehicle Tr.

[0055] Next, based on the angular velocity integral value θ (rotation angle) calculated in step S42 and the distance d of the railway vehicle Tr in the direction of the reference line R1 calculated in step S43, the perpendicular distance f from the reference line R1 to the current position of the railway vehicle Tr is calculated (vehicle position calculation step, step S44). In step S44, the perpendicular distance f is calculated multiple times within a predetermined time or while the vehicle is located at a predetermined distance from the branching point M0. The maximum value f1 and minimum value f2 of the perpendicular distance f to the current position of the railway vehicle Tr are calculated and stored each time, and the maximum value f1 and minimum value f2 of the perpendicular distance f to the current position of the railway vehicle Tr are calculated.

[0056] Next, an evaluation process is performed based on the calculated difference angles (vehicle position calculation step, step S45). In step S45, for example, the maximum value f1 or minimum value f2 of the perpendicular distance is set to a threshold value determined for each branch line R2 (perpendicular distance f shown by the dashed line L1 in Figure 3). When the railway vehicle Tr passes through the intersection P3 of the dashed line L1 and the branch line R2, the maximum value f1 or minimum value f2 of the perpendicular distance exceeds the perpendicular distance f at the intersection P3, so it is determined that the railway vehicle Tr is located on the branch line R2.

[0057] Furthermore, in step S45, for example, a threshold value is set for each reference line R1 (the distance in the direction of reference line R1 indicated by the dashed line L2 shown in Figure 3), and when the railway vehicle Tr passes through the intersection P4 of the dashed line L2 and reference line R1, the distance d exceeds the distance in the direction of reference line R1 at the intersection P4, so it is determined that the railway vehicle Tr is located on reference line R1.

[0058] Then, if the termination condition is met (if the result is "Y" in step S46), the evaluation process, i.e., the branch determination process, is terminated. If the termination condition is not met (if the result is "N" in step S46), the process returns to step S41 and the same process is repeated. Here, the termination condition can be any condition as long as it is possible to properly determine which railway track R the railway vehicle Tr is located on, that is, whether it is located on the base line R1 or the branch line R2. One example of a termination condition is when the determination result in step S45 is output by the position calculation unit 241.

[0059] <3. Effects> According to the vehicle approach warning system 1 of the embodiment, the on-board device (vehicle position detection device) 2 and vehicle position detection method allow a railway vehicle Tr traveling on either a reference line R1 or a branch line R2 branching off from the reference line R1 on the railway track R. At the branching point M0 between the reference line R1 and the branch line R2, the angular velocity, which indicates the angle of rotational speed of the railway vehicle Tr in the horizontal direction, is detected and acquired. The acquired angular velocity is integrated over time to calculate the angular velocity integral value θ. The distance d in the direction of the reference line R1 from the branching point M0 to the current position of the railway vehicle Tr is calculated. Based on the angular velocity integral value θ (rotation angle) and the distance d, the perpendicular distance f from the reference line R1 to the current position of the railway vehicle Tr is calculated. Based on the distance d and the perpendicular distance f, it is determined which railway track the railway vehicle Tr is located on, i.e., whether it is located on the reference line R1 or the branch line R2. In this way, it becomes possible to detect whether the railway vehicle Tr is located on the reference line R1 or the branch line R2. Furthermore, it becomes possible to detect which railway track a railway vehicle is located on without being affected by lateral position errors relative to the direction of travel of the railway vehicle Tr. In addition, since it only accesses a database to obtain threshold parameters, the computational load is reduced compared to other methods that access the database multiple times, thus contributing to a reduction in equipment costs. Moreover, even compared to methods that utilize neural networks, the computational load is reduced, thus contributing to a reduction in equipment costs.

[0060] Furthermore, the system stores the maximum and minimum values ​​f1 and f2 of the perpendicular distance f to the current position of the railway vehicle Tr. Based on either the maximum or minimum value f2 of the perpendicular distance, it determines which railway track the railway vehicle Tr is located on. This allows for more accurate determination of its position on the railway track.

[0061] Furthermore, if the maximum value f1 or minimum value f2 of the perpendicular distance f to the current position of the railway vehicle Tr reaches a threshold value determined for each branch line R2, it is determined that the railway vehicle Tr is located on branch line R2. Also, if the distance d of the railway vehicle Tr in the direction of the reference line R1 reaches a threshold value determined for each reference line R1, it is determined that the railway vehicle Tr is located on reference line R1. As a result, the amount of computation required for the determination process is reduced, which can contribute to reducing the cost of the device. In addition, since the threshold values ​​can be set based on various laws, regulations, and standards, the work involved in setting them becomes easier, which can contribute to reducing the cost of setting the threshold values.

[0062] Furthermore, by calculating the perpendicular distance f from the angular velocity detected by the sensor unit 220, the angular velocity is converted into distance and used to determine the position of the railway vehicle Tr. This makes it easier to build a database.

[0063] (Embodiment 2) Figure 6 is a schematic diagram showing a vehicle approach warning system 1A according to Embodiment 2, which uses the vehicle position detection device and vehicle position detection method of the present invention. This embodiment differs from Embodiment 1 in that the external device 6 includes a position calculation unit 61 and a railway GIS 62. Components equivalent to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0064] In other words, an external device 6 connected to the on-board device 2 is mounted on the railway vehicle Tr, and this external device 6 is equipped with a position calculation unit 61 and a railway GIS 62. The position calculation unit 61 performs the same functions as the position calculation unit 241 in Embodiment 1. The railway GIS 62 stores the same information as the railway GIS 231 in Embodiment 1. The angle (angular velocity) of the rotational speed detected by the sensor unit 220 is transmitted from the on-board device 2 to the external device 6 via the communication unit 210, and the position calculation unit 61 of the external device 6 detects which railway track R the railway vehicle Tr is located on (either the reference line R1 or the branch line R2). Thus, in this Embodiment 2, the on-board device 2 and the external device 6 constitute a vehicle position detection device.

[0065] According to this embodiment, for example, by using a computer capable of high-speed calculation processing as the external device 6, the position of the railway vehicle Tr can be calculated at high speed, and application software that supports the operation of the railway vehicle Tr can be operated using the calculated position information. In addition, it is possible to reduce the processing load on the onboard device 2 and suppress power consumption.

[0066] (Embodiment 3) Figure 7 is a schematic diagram showing a vehicle approach warning system 1B according to Embodiment 3, which uses the vehicle position detection device and vehicle position detection method of the present invention. This embodiment differs from Embodiment 1 in that the server device 4, which is located elsewhere than the railway vehicle Tr, is equipped with a position calculation unit 41 and a railway GIS 42. Components equivalent to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0067] In other words, the on-board device 2 is connected to a server device 4 that can communicate via a communication network NW, and is equipped with a position calculation unit 41 and a railway GIS 42. The position calculation unit 41 performs the same functions as the position calculation unit 241 in Embodiment 1. The railway GIS 42 stores the same information as the railway GIS 231 in Embodiment 1. The angle (angular velocity) of the rotational speed detected by the sensor unit 220 is transmitted from the on-board device 2 to the server device 4 via the communication unit 210, and the position calculation unit 41 of the server device 4 detects which railway track R the railway vehicle Tr is located on (either the reference line R1 or the branch line R2). Thus, in this Embodiment 3, the on-board device 2 and the server device 4 constitute a vehicle position detection device.

[0068] According to this embodiment, by detecting the positions of numerous railway vehicles Tr using the position calculation unit 41 of the server device 4, it is possible to reduce the cost of on-board equipment 2 installed on numerous railway vehicles Tr. Furthermore, since the position detection of numerous railway vehicles Tr can be processed collectively by the server device 4, the processing load on the on-board equipment 2 installed on each railway vehicle Tr can be reduced, and power consumption can be suppressed. In addition, when updating the function of the position calculation unit 24, only the position calculation unit 41 of the server device 4 needs to be changed, making it easy to update the function.

[0069] (Embodiment 4) Figure 8 is a flowchart showing the calculation procedure of the position calculation unit 241 in the on-board device 2 according to this embodiment. This embodiment differs from Embodiment 1 in that it corrects the position (kilometer mileage) of the railway vehicle Tr (hereinafter referred to as "kilometer mileage correction") in the later stage of the branching determination process. Components equivalent to those in Embodiment 1 are denoted by the same reference numerals and their explanation is omitted.

[0070] The position calculation unit 241 performs the calculation processes from step S1 to step S4 in the same manner as in Embodiment 1. Then, in the branch determination process, if it is not determined that the railway vehicle Tr is located on the branch line R2 (if the result is "N" in step S6), the track on which the railway vehicle Tr is located is determined (step S5), and the process returns to step S1 and the same process is repeated.

[0071] On the other hand, in the branching determination process, if it is determined that the railway vehicle Tr is located on branch line R2 (if "Y" is the result in step S6), it is determined whether the branching point M0 that was passed is a specific branching point M0 (vehicle position calculation step, step S7). If the branching point M0 that was passed is not a specific branching point M0 (if "N" is the result in step S7), the track on which the railway vehicle Tr is located is determined (step S5), and the process returns to step S1 and the same process is repeated.

[0072] On the other hand, if the passing junction M0 is a specific junction M0 (in the case of "Y" in step S7), a kilometer correction process is performed to correct the position (kilometers) of the railway vehicle Tr (step S8). After the kilometer correction process is completed, the track where the railway vehicle Tr is located is determined (step S5), and the process returns to step S1 and is repeated.

[0073] The details of the kilometer mileage correction process are as follows:

[0074] The position calculation unit 241 corrects the position (kilometers) of the railway vehicle Tr using the position (kilometers) of the branch point M0 when it determines that the railway vehicle Tr has passed a specific branch point M0 and is located on the branch line R2. More specifically, when it determines that the railway vehicle Tr is located on the branch line R2 (for example, when the railway vehicle Tr passes intersection P3 in Figure 3), that is, when the railway vehicle Tr has traveled a distance x along the branch line R2 from the specific branch point M0, the position (kilometers) of the railway vehicle Tr is overwritten and corrected to the position (kilometers) of the specific branch point M0 plus the distance x. The distance x can be determined by the Pythagorean theorem using the distance d in the direction of the reference line R1 from the specific branch point M0 to the current position of the railway vehicle Tr and the perpendicular distance f to the current position of the railway vehicle Tr.

[0075] Here, the specific junction M0 refers to the point where the branch line R2, which leads to and from bases such as train depots and maintenance bases, branches off from the base line R1. Since railway vehicles Tr always pass through such a specific junction M0 when entering and leaving a base, the position calculation unit 241 performs a kilometer marker correction when passing through the specific junction M0. Furthermore, since the setting value (kilometer marker, etc.) of the turnout installed at the specific junction M0 is stored in the GIS 231, performing the kilometer marker correction at the above timing makes it possible to correct based on accurate position information. Note that the position of a railway vehicle Tr on the branch line R2 after passing through the specific junction M0 can be detected by detecting the horizontal rotation (change in angular velocity) of the railway vehicle Tr, which always rotates horizontally when passing through the junction M0. However, since it is difficult to detect the exact moment of passing through the junction M0 (when passing through the junction M0), the kilometer marker correction is performed at the timing when it is determined that the railway vehicle Tr is positioned on the branch line R2.

[0076] Furthermore, the position (kilometer mileage) of the railway vehicle Tr subject to kilometer mileage correction is calculated based on, for example, positioning by GNSS, positioning by a radar speedometer, positioning by a sensor unit 220 (inertial sensors such as a gyro sensor and an acceleration sensor), or combined positioning by GNSS, a radar speedometer, and inertial sensors (for details of the calculation method, please refer to the specification of Japanese Patent Application Publication No. 2025-037274 by the present applicant). However, regardless of the positioning method used, it is not possible to completely eliminate the error in the calculated position (kilometer mileage) of the railway vehicle Tr. Therefore, it is meaningful to perform kilometer mileage correction at an appropriate time.

[0077] According to this embodiment, when it is determined that a railway vehicle has passed a specific junction M0 and is located on the branch line R2, the position of the railway vehicle Tr is corrected based on the position of junction M0, the distance d in the direction of the reference line R1 from junction M0 to the current position of the railway vehicle Tr, and the perpendicular distance f to the current position of the railway vehicle. As a result, cumulative position errors of the railway vehicle Tr can be automatically removed, and the estimation accuracy (kilometer marker accuracy) of the position of the railway vehicle Tr can be improved. Furthermore, by improving kilometer marker accuracy, the time that workers W must evacuate from their work positions for the passage of the railway vehicle Tr can be reduced in the vehicle approach warning system 1 using kilometer markers, thereby improving work efficiency.

[0078] Although embodiments of this invention have been described above, the specific configuration is not limited to the embodiments described above, and any design changes, etc., that do not depart from the gist of this invention are also included. For example, in the embodiments described above, a case in which a railway GIS and a position calculation unit are provided as a pair was described, but for example, the railway GIS may be provided on a separate computer server. [Explanation of symbols]

[0079] 1: Vehicle approach warning system 1A: Vehicle approach warning system 1B: Vehicle approach warning system 2: On-board equipment 3: Alarm terminal 4: Server device 6: External device 41:Position calculation section 61:Position calculation section 210: Communications Department 220: Sensor unit 230: Storage section 240: Control Unit 241:Position calculation section A1: Branch line angle area A2: Reference line angle area A3: Other areas 231: Railway GIS 42: Railway GIS 62: Railway GIS L1: Dashed line L2: Dashed line M0: Branch point NW: Communication Network P1: point P2: point P3: Intersection P4: Intersection R: Railway track R1: Reference line R2: Branch line Tr: Railway vehicles W: Worker d: distance f: Perpendicular distance f1: Maximum value f2: Minimum value θ: integral value of angular velocity

Claims

1. An angular velocity detection means for detecting the angular velocity, which indicates the angle of rotational speed in the horizontal direction of a railway vehicle running on a railway track, The system includes a vehicle position calculation means for calculating which railway track the aforementioned railway vehicle is located on, The aforementioned vehicle position calculation means is Near the branching point between the reference line on the railway track and the branch line branching off from the reference line, the angular velocity of the railway vehicle detected by the angular velocity detection means is acquired. The distance in the direction of the reference line from the aforementioned branching point to the current position of the railway vehicle is calculated, Based on the acquired angular velocity of the railway vehicle and the calculated distance of the railway vehicle in the direction of the reference line, the perpendicular distance from the reference line to the current position of the railway vehicle is calculated. Based on the calculated distance of the railway vehicle in the direction of the reference line and the calculated perpendicular distance to the current position of the railway vehicle, it is determined which railway track the railway vehicle is located on. A vehicle position detection device characterized by the following features.

2. It is equipped with a map information storage means that stores map information including the latitude and longitude of each point on multiple railway tracks, The aforementioned vehicle position calculation means is Based on the map information, when it is detected that the railway vehicle is approaching the branching point between the reference line on the railway track and the branch line branching off from the reference line, the angular velocity of the railway vehicle detected by the angular velocity detection means is acquired. The vehicle position detection device according to claim 1.

3. The aforementioned vehicle position calculation means is The process of obtaining the angular velocity of the railway vehicle, calculating the distance of the railway vehicle in the direction of the reference line, calculating the perpendicular distance to the current position of the railway vehicle, and determining which railway track the railway vehicle is located on is repeated at predetermined intervals. The vehicle position detection device according to claim 1.

4. The aforementioned vehicle position calculation means is The angular velocity of the railway vehicle obtained above is integrated over time to calculate the integral value of the angular velocity, and based on the integral value of the angular velocity, the distance in the direction of the reference line from the branching point to the current position of the railway vehicle is calculated. A vehicle position detection device according to any one of claims 1 to 3, characterized by the features described above.

5. The aforementioned vehicle position calculation means is The system calculates the perpendicular distance to the current position of the railway vehicle multiple times within a predetermined time, stores the maximum and minimum values ​​of the perpendicular distance to the current position of the railway vehicle, and determines which railway track the railway vehicle is located on based on the calculated maximum and minimum values ​​of the perpendicular distance to the current position of the railway vehicle. The vehicle position detection device according to claim 1.

6. The aforementioned vehicle position calculation means is If the maximum or minimum value of the perpendicular distance to the current position of the railway vehicle calculated above reaches a threshold value determined for each branch line, it is determined that the railway vehicle is located on that branch line. The vehicle position detection device according to claim 5.

7. The aforementioned vehicle position calculation means is If the maximum or minimum value of the perpendicular distance to the current position of the railway vehicle, calculated as described above, reaches a threshold value determined for each branch line, and falls outside a predetermined range, it is determined that the determination is impossible. The vehicle position detection device according to claim 6.

8. The aforementioned vehicle position calculation means is If the calculated distance of the railway vehicle in the direction of the reference line reaches a threshold value determined for each reference line, it is determined that the railway vehicle is located on that reference line. The vehicle position detection device according to claim 1.

9. The aforementioned vehicle position calculation means is If the calculated distance of the railway vehicle in the direction of the reference line reaches a threshold value determined for each reference line, and is outside a predetermined range, then it is determined that the determination is impossible. The vehicle position detection device according to claim 8.

10. The aforementioned vehicle position calculation means is If the position of the aforementioned railway vehicle cannot be determined, a prescribed notification will be given. The vehicle position detection device according to claim 9.

11. The aforementioned vehicle position calculation means is Based on the aforementioned map information, the distance in the direction of the reference line from the branching point to the current position of the railway vehicle is calculated. The vehicle position detection device according to claim 2, characterized in that it is as described above.

12. The aforementioned vehicle position calculation means is Based on the speed of the railway vehicle detected by the speed detection means provided in the railway vehicle for detecting the speed of the railway vehicle, the distance in the direction of the reference line from the branching point to the current position of the railway vehicle is calculated. The vehicle position detection device according to claim 1.

13. The aforementioned vehicle position calculation means is When it is determined that the aforementioned railway vehicle has passed a specific junction and is located on the aforementioned junction line, The position of the railway vehicle is corrected based on the position of the junction, the distance in the direction of the reference line from the junction to the current position of the railway vehicle, and the perpendicular distance to the current position of the railway vehicle. The vehicle position detection device according to claim 6.

14. A vehicle position detection method to be executed by a computer comprising a processor and a memory unit, The aforementioned memory unit stores map information including the latitude and longitude of each point on multiple railway tracks. The processor performs an angular velocity detection step in which it detects the angular velocity, which indicates the angle of rotational speed in the horizontal direction of a railway vehicle running on the railway track, The process involves performing a vehicle position calculation step to determine which railway track the aforementioned railway vehicle is located on, In the aforementioned vehicle position calculation step, Based on the aforementioned map information, it is detected that the railway vehicle is approaching the branching point between the reference line on the railway track and the branch line branching off from the reference line. The angular velocity of the railway vehicle detected in the angular velocity detection step is obtained, The distance in the direction of the reference line from the aforementioned branching point to the current position of the railway vehicle is calculated, Based on the acquired angular velocity of the railway vehicle and the calculated distance of the railway vehicle in the direction of the reference line, the perpendicular distance from the reference line to the current position of the railway vehicle is calculated. Based on the calculated distance of the railway vehicle in the direction of the reference line and the calculated perpendicular distance to the current position of the railway vehicle, it is determined which railway track the railway vehicle is located on. A vehicle position detection method characterized by the above.

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