EP4501743A1

EP4501743A1 - Train control system and train control method

Info

Publication number: EP4501743A1
Application number: EP22935693.6A
Authority: EP
Inventors: Taishi HATTORI; Masahiro Aoyama
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2022-03-31
Filing date: 2022-12-09
Publication date: 2025-02-05
Also published as: EP4501743A4; JP7747880B2; AU2022450317A1; WO2023188564A1; JPWO2023188564A1

Abstract

A train control system to be installed on a train that moves along a predetermined route and control the train includes: a position acquisition unit configured to acquire an on-rail position of the train; a database configured to store a plurality of operation patterns, a relationship between a signal indication of a ground railway signal and a speed limit, and a plurality of ground railway signals and a plurality of block sections on the route; a camera configured to image a ground railway signal in a block section on the on-rail position and output indication information; and an on-board control unit configured to calculate, based on the speed limit corresponding to the indication information, a travel permission position and a travelable route that enables traveling to the travel permission position, and control traveling of the train based on the travel permission position and the travelable route.

Description

Technical Field

The present invention relates to a train control system and a train control method.

Background Art

In order to operate a train automatically, an introduction of a train control system, that is, an automatic train operation (ATO) system is being considered, in which a train is given an operation target such as a target time to arrive at a next station, and the train travels in accordance with the target. In many ATO systems, when a specific train is determined to be delayed compared to a scheduled time, or when a specific train is given a target (time, position, speed) by an operation management system to reach when (time), where (position), and at what speed (speed), the train regenerates a target run curve (an operation pattern) and performs speed control so as to reach the target.
For example, PTL 1 discloses that, when operating a train autonomously, a target speed is automatically calculated based on a reference travel time between stations and a travel time of an own train in order to travel according to a schedule, and on the other hand, a command such as a power traveling, a brake, and coasting is issued in consideration of weather, a delay state of a train, or the like, and therefore an operation method can change according to the situation and operating can be adapted to the situation.

Citation List

Patent Literature

PTL 1: JPH11-255126A

Summary of Invention

Technical Problem

On a railroad section with a low number of passengers per day, such as a local railroad section, it is costly to introduce a safety device such as an automatic train control (ATC) device that performs train control using continuous on-rail detection and a signal indication displayed in the train, which is used on a railroad section with a large number of passengers in urban areas. Therefore, it is common to use an automatic train stop (ATS) device that controls a train at any point using a ground element and a ground railway signal. The ATO system may also be considered to operate automatically using only an on-board control device mounted on the train, without cooperating with an operation management device that can grasp an operation state of each train and compare an actual operation state with an operation plan.
In the technique described in PTL 1, a signal indication of a railway signal installed on the ground is recognized by a camera, and a speed at which a train travels is calculated using a relationship among a railway signal position registered in a database, an indication of the railway signal, and a speed limit, and a position detection method. However, since a relationship between an own train and a preceding train or an oncoming train on a single line cannot be grasped, it is difficult to maintain a train interval when a delay occurs.

Solution to Problem

A train control system according to an aspect of the invention is a train control system to be installed on a train that moves along a predetermined route and control the train. The train control system includes: a position acquisition unit configured to acquire an on-rail position of the train; a database configured to store a plurality of operation patterns, a relationship between a signal indication of a ground railway signal and a speed limit, and a plurality of ground railway signals and a plurality of block sections on the route; a camera configured to image a ground railway signal in a block section on the on-rail position and output indication information; and an on-board control unit configured to calculate, based on the speed limit corresponding to the indication information, a travel permission position and a travelable route that enables traveling to the travel permission position, and control travelling of the train based on the travel permission position and the travelable route. The on-board control unit includes a measurement unit that measures, when an indication of the indication information changes to an indication other than proceeding, a time interval from a time of the change to a time when the indication of the indication information changes again, a search unit configured to search, based on the indication information during the measurement, the database for a block section where a preceding train is on-rail, and a prediction unit configured to predict an average speed of the preceding train based on the time interval and the block section searched by the search unit. Travelling of the train is controlled based on the average speed predicted by the prediction unit.
A train control method according to an aspect of the invention includes: measuring, when an indication of indication information of a ground railway signal in a block section where a train is on-rail changes to an indication other than traveling, a time interval from a time of the change to a time when the indication of the indication information changes again; searching, based on the indication information during the measurement, a database storing a plurality of block sections on the route for a block section where a preceding train is on-rail; predicting an average speed of the preceding train based on the time interval and the searched block section; and controlling travelling of the train based on the predicted average speed.

Advantageous Effects of Invention

According to the invention, since the average speed of the preceding train can be predicted, deviation of a train interval from a plan can be prevented, and an occurrence of congestion can be reduced.

Brief Description of Drawings

[FIG. 1] FIG. 1 is a diagram illustrating an embodiment of a train control system according to the invention.
[FIG. 2] FIG. 2 is a diagram illustrating a relationship among a train, a travelable route, and a travel permission position when a stop point is set between stations up to a predetermined stop station.
[FIG. 3] FIG. 3 is a diagram illustrating a relationship among a traveling position of a preceding train, a traveling position of an own train, and an indication of a ground railway signal at a time t1.
[FIG. 4] FIG. 4 is a diagram illustrating a relationship among a traveling position of the preceding train, a traveling position of the own train, and an indication of the ground railway signal at a time t2 = t1 + Δt.
[FIG. 5] FIG. 5 is a diagram illustrating an example of a traveling pattern of the own train and the preceding train from a time t11 to a time t13.
[FIG. 6] FIG. 6 is a diagram illustrating another example of the traveling pattern of the own train and the preceding train from the time t11 to the time t13.
[FIG. 7] FIG. 7 is a flowchart illustrating an example of control processing.
[FIG. 8] FIG. 8 is a flowchart illustrating processing subsequent to the processing in FIG. 7.
[FIG. 9] FIG. 9 is a flowchart illustrating an example of control processing according to Modification 1.
[FIG. 10] FIG. 10 is a flowchart illustrating processing subsequent to the processing in FIG. 9.
[FIG. 11] FIG. 11 is a flowchart illustrating Modification 2.

Description of Embodiments

Hereinafter, an embodiment according to the invention will be described with reference to the drawings. The following description and drawings are examples for illustrating the invention, and are appropriately omitted and simplified for clarity of the description. In the following description, the same or similar elements and processing are denoted by the same reference numerals, and redundant descriptions thereof may be omitted. The content described below is merely an example of the embodiment of the invention, and the invention is not limited to the embodiment to be described below, and can be implemented in various other embodiments.
FIG. 1 is a diagram illustrating a train control system according to an embodiment of the invention, and is a block diagram illustrating a schematic configuration of a train control system 10. The train control system 10 of the present embodiment is an on-board control device mounted on a train 11, and causes the train 11 traveling on a line 121 to operate along a travel trajectory 126. The train control system 10 includes an on-board control unit 100, a camera 110, a database 111, and a position acquisition unit 112.
The camera 110 includes an imaging element such as a CMOS image sensor, and images a ground railway signal 124 in a block section where the train 11 is on-rail in a traveling direction. The camera 110 recognizes an indication of the imaged ground railway signal 124 and outputs recognized indication information to the on-board control unit 100. The position acquisition unit 112 acquires an on-rail position of the train 11. As the position acquisition unit 112, for example, a GPS device mounted on the train 11 is used. Alternatively, the position may be calculated by acquiring speed information from a speedometer provided in the train 11 and integrating the speed with time. The database 111 stores an operation pattern, information on a ground railway signal (a position of the railway signal and a type of the railway signal), a block section on a travel route, a relationship between a signal indication and a speed limit 125, a point (a stop point) where a speed limit is 0 km/h, and the like.
The on-board control unit 100 includes a measurement unit 101, a calculation unit 102, and a search unit 103. Functions and operations of the measurement unit 101, the calculation unit 102, and the search unit 103 will be described later. The on-board control unit 100 controls an operation of the train at a speed less than the speed limit 125 and a speed at a travel permission position 123, which is set to 0 km/h, based on an arrival station 122 and the travel permission position 123, and an operation pattern to be mounted in the database 111. The travel trajectory 126 represents a trajectory along which the train 11 actually travels (or has traveled), with a vertical axis representing a speed of the train 11 and a horizontal axis representing a position of the train 11. For the speed limit 125, a vertical axis also represents the speed of the train 11 and a horizontal axis also represents the position of the train 11.
The on-board control unit 100 includes a microcomputer, a processor, and a calculation device similar to these, and a ROM, a RAM, a flash memory, a hard disk, an SSD, a memory card, an optical disk, and a storage device similar to these, and implements functions of the measurement unit 101, the calculation unit 102, the search unit 103, or the like by executing a program stored in the storage device.
FIG. 2 is a diagram illustrating a relationship among a train, a travelable route, and a travel permission position when a stop point is set between stations up to a predetermined stop station. FIG. 2 illustrates a case where an indication of a ground railway signal 124A is stop (hereinafter, referred to as a "stop indication") due to on-rail of a preceding train (not illustrated). When the ground railway signal indicates stop, there is a point where the speed limit is 0 km/h in the block section where the train 11 is on-rail. That is, there is a point where the speed limit is 0 km/h on a side of the train 11 with respect to the ground railway signal 124A indicating stop.
When there is a point where the speed limit is 0 km/h in a travel section up to the arrival station 122 due to on-rail of a preceding train (not illustrated) in this way, the on-board control unit 100 sets a travel permission position 123A before update outside the point where the speed limit is 0 km/h, that is, on a side where the train 11 is on-rail from the stop point. Then, the on-board control unit 100 sets a travelable route 120A from an on-rail position of the train 11 to the travel permission position 123A.
Thereafter, when a ground railway signal 124B indicates stop and the ground railway signal 124A changes from the stop indication to a caution indication due to traveling of the preceding train, the speed limit changes from the speed limit 125A before update to a speed limit 125B after update. With the change to the speed limit 125B, the on-board control unit 100 sets an updated travel permission position 123B with the arrival station 122 as an upper limit and a travelable route 120B after the travel permission position update. Then, the on-board control unit 100 operates along a travel trajectory 126B after the travel permission position update at a speed less than the updated speed limit 125B.
FIGS. 3 and 4 are diagrams illustrating a relationship between a change in traveling position of a preceding train and an own train and a signal indication change of a ground railway signal. In the present embodiment, a case of a ground railway signal with three indications (blue, yellow, and red) will be described as an example, but the number and type of indications that can be expressed are not limited. For example, in addition to a block railway signal, any ground railway signal such as a departure railway signal, an in-site railway signal, a relay railway signal, and a switching railway signal is included. An own train 11A and a preceding train 11B travel along the line 121 in a right direction in the drawing. FIG. 3 is a diagram illustrating a relationship between a traveling position of the preceding train 11B and the own train 11A and an indication of a ground railway signal at a time t1. FIG. 4 is a diagram illustrating a relationship between a traveling position of the preceding train 11B and the own train 11A and an indication of the ground railway signal at a time t2 = t1 + Δt.
Generally, the ground railway signal indicates an indication of traveling (hereinafter, referred to as a traveling indication) when a line ahead is open. When a preceding train is on the line, the ground railway signal indicates a stop indication in response to an entry into a block section where the preceding train is on-rail. For a block section located outside the stop indication, the ground railway signal indicates a next lower speed limit (a caution indication in the case of three indications) after the stop indication. In this way, in a block section between the stop indication and the traveling indication, an indication with a different speed limit, one level at a time is indicated.
At the time t1 illustrated in FIG. 3, the own train 11A is on-rail of a block section B1, and the preceding train 11B is on-rail of a block section B4. Ground railway signals 124A, 124D, and 124E indicate a traveling indication. A ground railway signal 124C indicates a stop indication. The ground railway signal 124B indicates a caution indication.
At the time t2 = t1 + Δt illustrated in FIG. 4, the preceding train 11B moves to a block section B5, and the own train 11A moves to a block section B3. In this situation, the ground railway signals 124B and 124D indicate a stop indication. The ground railway signals 124A and 124C indicate a caution indication. The ground railway signal 124E indicates a traveling indication.

(Operation Description)

Next, an operation of the on-board control unit 100 in a case where there is a point where the speed limit is 0 km/h between the on-rail position of the train and the arrival station as illustrated in FIG. 2 due to the influence of the preceding train will be described. The on-board control unit 100 constantly causes the camera 110 to recognize an indication of a ground railway signal on a front side of traveling in the block section where the train is on-rail, and performs traveling in an operation pattern at a speed less than the speed limit indicated by the ground railway signal. The indication indicated by the ground railway signal indicates a speed limit for a section inside the ground railway signal. For example, in the case of FIG. 2, the indication indicated by the ground railway signal 124A indicates a speed limit in a block section between the ground railway signal 124A and the ground railway signal 124B.
When the own train 11A enters a next block section due to traveling, in a case where it is recognized that the indication of the ground railway signal ahead of the own train 11A after entry is other than traveling due to the influence of the preceding train 11B, the on-board control unit 100 operates as follows. The on-board control unit 100 changes the operation pattern of the own train 11A to an operation pattern in which the own train 11A is traveling at a speed less than an indicated speed limit until the own train 11A enters a block section corresponding to the ground railway signal. At a time point when the camera 110 recognizes that the indication of the ground railway signal is other than traveling, the on-board control unit 100 starts timing using the measurement unit 101, and measures a time until a next indication change of the ground railway signal is recognized within the block section where the own train 11A is on-rail.
Here, there are the following two cases as a situation in which the camera 110 recognizes the indication change. A first case is a case where, regardless of the influence of traveling of the preceding train 11B, the block section where the own train 11A is on-rail changes and the recognized ground railway signal changes to another ground railway signal having different indication. A second case is a case where the block section where the preceding train 11B is on-rail changes and the indication of the ground railway signal recognized by the camera 110 changes.
For example, the indication change in the above first case is illustrated in FIG. 3, where the own train 11A enters a next block section B2 when the preceding train 11B is on-rail of the block section B4. In this case, the indication of the ground railway signal recognized by the camera 110 changes from a traveling indication to a caution indication. The ground railway signal 124B ahead of the own train 11A after entry indicates caution, and thus the measurement unit 101 measures a time from a time point after entry to a time of a next change in indication of the ground railway signal.
The search unit 103 of the on-board control unit 100 searches for the block section where the preceding train 11B is on-rail based on an indication of the ground railway signal to be recognized and information on the block section registered in the database. Then, the calculation unit 102 of the on-board control unit 100 predicts an average speed of the preceding train 11B based on a distance of the block section B4 through which the preceding train 11B travels and a measurement time between the indication changes that is measured by the measurement unit 101. Further, the on-board control unit 100 changes the operation pattern of the own train 11A based on the average speed of the preceding train 11B that is predicted by the calculation unit 102 in order to prevent an operation interval with the preceding train 11B from being clogged.
A time measurement by the measurement unit 101 is started from a time point when the camera 110 recognizes the indication change of the ground railway signal. Therefore, prediction accuracy in the case of performing the time measurement based on the indication change recognized by the camera 110 is higher as a time from when the indication of the ground railway signal changes to when the indication change is recognized by the camera 110 is shorter. This will be described in detail with reference to FIG. 5.
FIG. 5 is a diagram illustrating a situation from when the preceding train 11B moves from the block section B3 to the block section B4 and the ground railway signal 124B changes to the caution indication at a time t11 to when the preceding train 11B leaves the block section B4 and the ground railway signal 124B changes to the traveling indication at a time t13. The ground railway signal 124B changes from the stop indication to the caution indication at the time t11 when the preceding train 11B enters the block section B4. At this time, the own train 11A is on-rail of the block section B1, and thus the camera 110 does not recognize the ground railway signal 124B. The camera 110 recognizes the indication (the caution indication) of the ground railway signal 124B at the time t12 when the own train 11A enters the block section B2. Then, the camera 110 recognizes that the indication of the ground railway signal 124B changes from the caution indication to the traveling indication at the time t13 when the preceding train 11B leaves the block section B4.
In this case, a time from when the ground railway signal 124B changes to the caution indication to when the ground railway signal 124B changes to the traveling indication is t13 - t11. On the other hand, a time from when the own train 11A enters the block section B2 and the camera 110 recognizes the caution indication of the ground railway signal 124B to when the camera 110 recognizes that the indication of the ground railway signal 124B changes from the caution indication to the traveling indication is t13 - t12. A difference between the two times is a difference = (t13 - t11) - (t13 - t12) = t12 - t11. That is, the prediction accuracy of the average speed of the preceding train 11B is higher as the difference = t12 - t11, which is a time from when the indication of the ground railway signal 124B changes to the caution indication to when the change is recognized by the camera 110, is shorter.
Since the time measurement by the measurement unit 101 is performed only within the block section where the own train 11A is on-rail, the time measurement ends halfway when the own train 11A leaves the block section where the train 11A is on-rail. Therefore, the prediction accuracy of the average speed is higher as a time from when the measurement ends to when the preceding train 11B leaves the block section and the indication of the ground railway signal changes is shorter. This will be described in detail with reference to FIG. 6.
In FIG. 6, at the time t11, the preceding train 11B moves from the block section B3 to the block section B4, and the ground railway signal 124B changes from the stop indication to the caution indication. At the time of the indication change (t11), the camera 110 on the own train 11A being on-rail of the block section B2 recognizes the indication change. Thereafter, at the time t12 when the preceding train 11B is on-rail of the block section B4, the own train 11A moves from the block section B2 to the block section B3. The ground railway signal recognized by the camera 110 changes from the ground railway signal 124B indicating caution to the ground railway signal 124C indicating stop, and thus the camera 110 recognizes that the indication changes from the caution indication to the stop indication. Thereafter, when the preceding train 11B leaves the block section B4 at the time t13, the ground railway signal 124C changes from the stop indication to the caution indication.
In this case, the timing of the measurement unit 101 based on the indication change recognition of the camera 110 is performed in an on-rail section (the block section B2) at the time t11 when the own train 11A recognizes the caution indication of the ground railway signal 124B (that is, an indication change from the stop indication to the caution indication). Therefore, at the time t12 when the own train 11A ends traveling in the block section B2, the timing of the measurement unit 101 ends halfway. The measurement time when the timing ends halfway is t12 - t11. However, a time when the ground railway signal 124B changes from the caution indication to the traveling indication is t13, and thus the measurement time is shortened by the difference = t13 - t12. That is, it is understood that the prediction accuracy of the average speed is higher as a time from when the time measurement ends halfway to when the ground railway signal 124B changes to the traveling indication is shorter.
FIGS. 7 and 8 are flowcharts illustrating an example of control processing executed by the on-board control unit 100. The control processing illustrated in FIGS. 7 and 8 is repeatedly executed again even after the control processing ends. A supplementary description will be made as appropriate with reference to FIG. 5 as a specific example. In step S200 in FIG. 7, the on-board control unit 100 acquires indication information on the ground railway signal from the camera 110. The indication information is information indicating whether the indication recognized by the camera 110 is a traveling indication, a caution indication, or a stop indication. The on-board control unit 100 includes the storage device as described above, and the storage device is provided with a first memory and a second memory for storing indication information. When the indication information is acquired in step S200, the indication information stored in the first memory is moved to the second memory, and then data in the first memory is rewritten with the acquired indication information.
In step S201, the on-board control unit 100 determines whether the above-described indication information acquired in step S200 and stored in the first memory is a traveling indication. When it is determined in step S201 that the indication information is the traveling indication (Y), a series of control processing ends. When the ground railway signal indicates traveling, it is possible to travel as planned, and thus a current travel permission position and a current operation pattern are maintained. On the other hand, when it is determined in step S201 that the indication information is an indication other than traveling (N), step S202 is executed.
In the example illustrated in FIG. 5, it is determined as (Y) in step S201 at the time t11 (the traveling indication) and the series of control processing ends, after which the processing is restarted from START. When it is determined as "N" in step S201 at the time t12 (the caution indication), the processing proceeds to step S202. At this time, the currently recognized caution indication is stored in the above-described first memory, and the previously recognized traveling indication is stored in the second memory.
In step S202, the on-board control unit 100 determines whether the indication information is a stop indication. When it is determined in step S202 that the indication information is a stop indication(Y), the processing proceeds to step S203. When the ground railway signal indicates stop, there is a point where the speed limit is 0 km/h in the block section where the own train 11A is on-rail. Therefore, in step S203, the on-board control unit 100 changes the current travel permission position and the current operation pattern to a travel permission position and an operation pattern capable of allowing traveling to an outside of the ground railway signal where the speed limit is 0 km/h. On the other hand, when it is determined in step S202 that the indication information is an indication indicating other than stop (N), the processing proceeds to step S204.
In step S204, the on-board control unit 100 determines whether the indication information stored in the first memory is different from the indication information stored in the second memory, that is, whether the recognized indication changes. When it is determined in step S204 that the indication changes (Y), the processing proceeds to step S205. When it is determined that the indication does not change (N), the series of control processing ends.
In the example illustrated in FIG. 5, when the own train 11A enters the block section B2 at the time t12, the processing proceeds in order of step S201, step S202, and step S204. At this time, the caution indication is stored in the first memory and the traveling indication is stored in the second memory, and thus it is determined in step S204 that the indication changes (Y), and the processing proceeds to step S205.
In step S205, the on-board control unit 100 determines whether the ground railway signal recognized by the camera 110 is an application target ground railway signal. When it is determined in step S205 that the ground railway signal is an application target railway signal (Y), the processing proceeds to step S206. When it is determined that the ground railway signal is not an application target railway signal (N), the series of control processing ends. In the next control processing to be started again, a measurement operation is restarted from beginning.
Here, the application target ground railway signal is a ground railway signal that is disposed near an arrival station and whose indication always changes such that the inside of the arrival station is a stop indication. At a terminal station and the like, a ground railway signal (a home railway signal) is provided that always indicates stop on the inside of the arrival station, and when the own train 11A approaches the arrival station, the indication changes to an indication other than traveling regardless of whether the preceding train 11B is present. When the indication change of the railway signal such as a home railway signal is determined to be used as start and end conditions for timing when predicting the average speed of the preceding train, an erroneous determinations is made. Therefore, it is determined whether the ground railway signal is an application target ground railway signal (a ground railway signal other than a ground railway signal that always indicates other than traveling) based on the ground railway signal information registered in the database 111 of the train control system 10.
In step S206, the on-board control unit 100 starts timing by the measurement unit 101. In the example in FIG. 5, the timing is started at a time point (the time t12) when the own train 11A enters the block section B2. When the timing is started in step S206, the processing proceeds to step S301 in FIG. 8.
In step S301 in FIG. 8, the on-board control unit 100 determines whether the own train 11A ends traveling in the block section where the own train 11A is on-rail, that is, whether the own train 11A enters a next block section. When it is determined in step S301 that the own train 11A does not end the traveling in the block section where the own train 11A is on-rail (N), the processing proceeds to step S304. When it is determined that the own train 11A ends the traveling in the block section where the own train 11A is on-rail (Y), the processing proceeds to step S302.
First, a case where the processing proceeds from step S301 to step S304 will be described. In step S304, the on-board control unit 100 acquires indication information of the ground railway signal from the camera 110. When the indication information is acquired in step S304, the indication information stored in the first memory is moved to the second memory, and then data in the first memory is rewritten with the acquired indication information. Next, in step S305, the on-board control unit 100 compares the indication information in the first memory with the indication information in the second memory, and determines whether the indication recognized by the camera 110 changes. When it is determined in step S305 that the indication changes (Y), the processing proceeds to step S306. When it is determined that the indication does not change (Y), the processing returns to step S301.
The processing from step S301 to step S304 will be described with reference to FIG. 5 ,as an example. In the example illustrated in FIG. 5, the timing is started at the time t12 as described above. Before the own train 11A passes through the block section B2, the preceding train 11B passes through the block section B4 at the time t13, and the ground railway signal 124B changes from a caution indication to a traveling indication. Therefore, the processing proceeds from step S301 to step S304, and the indication information is acquired from the camera 110. As a result, the indication information in the first memory is a traveling indication and the indication information in the second memory is a caution indication, and it is determined in step S305 that the indication changes (Y), and the processing proceeds to step S306.
In a case where the own train 11A ends traveling in the block section B2 before the time t13, before it is determined in step S305 that the indication changes, it is determined in step S301 that the own train 11A ends the traveling in the block section B2 where the own train 11A is on-rail (Y), and the processing proceeds to step S302.
In step S306, as in the case of step S205 described above, the on-board control unit 100 determines whether the ground railway signal recognized by the camera 110 is an application target ground railway signal. When it is determined in step S306 that the ground railway signal is an application target railway signal (Y), the processing proceeds to step S307, and the timing by the measurement unit 101 ends. On the other hand, when it is determined in step S306 that the ground railway signal is not an application target railway signal (N), the series of the control processing ends.
In step S308, when the own train 11A travels using the current operation pattern, the on-board control unit 100 determines whether a lower indication is expected in a next block section, that is, whether the speed limit in the next block section is expected to be lower than that in the block section where the own train 11A is on-rail in consideration of a distance of the block section where the preceding train 11B is on-rail, a speed of the own train 11A, a distance of the block section where the own train 11A is on-rail, and the like. When it is determined in step S308 that the lower indication is expected (Y), the processing proceeds to step S310. When it is determined that the lower indication is not expected (N), the processing proceeds to step S309.
When the processing proceeds from step S308 to step S309, no lower indication is expected in the next block section, and thus the on-board control unit 100 changes the current operation pattern to an operation pattern capable of reducing a delay within the speed limit, and the series of control processing ends.
When the processing proceeds from step S308 to step S310, the calculation unit 102 of the on-board control unit 100 searches the database 111 for a distance of the block section where the preceding train 11B is on-rail, and predicts the average speed of the preceding train 11B based on the distance of the block section and the measurement time measured by the measurement unit 101. In step S311, the on-board control unit 100 changes, based on the average speed predicted in step S310, the current operation pattern to an operation pattern capable of reducing an approach to (a reduction in operation interval with) the preceding train 11B, and the series of control processing ends.
On the other hand, a case will be described in which it is determined in step S301 that the own train 11A ends the traveling in the block section where the own train 11A is on-rail (Y), and the processing proceeds to step S302. In step S302, the on-board control unit 100 ends the time measurement by the measurement unit 101 halfway. In step S303, the on-board control unit 100 selects an average speed prediction value that is a maximum speed from a plurality of average speeds predicted by the calculation unit 102 during traveling on the line 121, and changes, based on the average speed prediction value, the current operation pattern to the operation pattern capable of reducing a reduction in operation interval with the preceding train 11B.
The control processing illustrated in FIGS. 7 and 8 is repeatedly executed while the own train 11A is traveling on the line 121, and thus the average speed prediction value is obtained each time the time measurement is repeated. The reason why the average speed prediction value under highest speed conditions is selected from within a predictable range is to prevent a delay caused by changing the operation pattern based on an erroneous determination due to variations in prediction accuracy. Once step S303 is executed, the series of control processing ends.
According to the train control system 10 of the present embodiment, by monitoring the indication change of the ground railway signal in the case where a delay occurs or the like, the approximate position and the average speed of the preceding train can be predicted, and the operation pattern that prevents the operation interval between the own train and the preceding train from becoming too short can be calculated. Accordingly, even in an ATO system in which an operation management device and an on-board control device are not cooperated with each other, the train interval can be prevented from deviating from the plan and the occurrence of congestion can be reduced.

(Modification 1)

In the above-described embodiment, the time between the indication changes is measured within the block section where the own train 11A is on-rail, and the average speed of the preceding train is calculated based on the measurement time measured in the one block section. Therefore, as the processing in order of step S301 and step S302 in FIG. 8, when the traveling in the block section where the own train 11A is on-rail ends, the timing by the measurement unit 101 ends halfway.
In Modification 1, when an own train travels through a plurality of block sections while a preceding train travels from one end to the other end of one block section, a time measured in each block section is added to estimate a travel time of the preceding train. FIGS. 9 and 10 are flowcharts illustrating an example of control processing according to Modification 1. In Modification 1, as illustrated in FIG. 10, step S303 in FIG. 8 is deleted, and control changes such that the process proceeds from step S302 to step S206 in FIG. 9. The other processing in FIGS. 9 and 10 is the same as the flowchart illustrated in FIGS. 7 and 8, and thus only different steps will be described below with reference to FIG. 6.
In FIG. 6, when the indication recognized by the camera 110 at the time t11 (the indication of the ground railway signal 124B) changes from the stop indication to the caution indication, it is determined as (Y) in step S204 in FIG. 9, the processing proceeds in order of step S205 and step S206, and the timing by the measurement unit 101 starts. From the time t11 to the time t12, processing in order of step S301, step S304, step S305, and step S301 is repeated.
When the own train 11A moves from the block section B2 to the block section B3 at the time t12, the processing proceeds from step S301 to step S302 in FIG. 10, and the timing is interrupted. The measurement time in the case of being interrupted is stored for used in a later calculation. At the time of the interruption, the own train 11A passes through the block section B2, and thus the camera 110 recognizes the stop indication of the ground railway signal 124C. Therefore, the stop indication is stored in the first memory, and the caution indication is stored in the second memory.
When the processing in step S302 ends, the processing proceeds to step S206 in FIG. 9, and the measurement by the measurement unit 101 starts again. Thereafter, the processing proceeds in order of step S301 and step S304, and the indication information is acquired in step S304. As can be seen from FIG. 6, the indication information acquired from the camera 110 is the stop indication, and thus when step S304 is executed, data in the second memory is rewritten from the caution indication to the stop indication, and data in the first memory and the second memory are all stop indications. Therefore, it is determined as (N) in step S305, and the processing proceeds to step S301.
From the time t12 to the time t13 in FIG. 6, the indication information recognized by the camera 110 is the stop indication, and thus the processing in order of step S301, step S304, step S305, and step S301 is repeated until the time t13 is reached. Then, at the time t13 when the preceding train 11B moves from the block section B4 to the block section B5, the recognized indication information (the indication of the ground railway signal 124C) changes from the stop indication to the caution indication. As a result, it is determined as (Y) in step S305, the processing proceeds in order of step S305, step S306, and step S307, and the timing by the measurement unit 101 ends in step S307.
A measurement result when the timing is interrupted in step S302 is (t12 - t11), and a measurement result measured in step S307 is (t13 - t12). The on-board control unit 100 determines that the measurement result (t12-t11) and the measurement result (t13-t12) obtained in this way are time-continuous data. Then, a value (t13 - t11) obtained by adding the measurement results is regarded as a time during which the preceding train 11B travels through one block section B4, and is used for calculating the average speed of the preceding train 11B.
When Modification 1 is applied to a case where the own train 11A, as illustrated by the dashed line in FIG. 5, is on-rail of the block section B3 rather than the block section B2 at the time t13, the following operation is performed. In this case, while the preceding train 11B travels from one end to the other end of the block section B4, the own train 11A travels from the block section B1 to the block section B3. Therefore, after the timing is started at the time t11, the own train 11A ends traveling in the block section twice in the case of B1 to B2 and the case of B2 to B3. That is, the timing interruption processing in step S302 occurs twice. By adding up the two measurement times obtained by two timing interruptions and the measurement time obtained when the measurement ends at the time t13, a time required for the preceding train 11B to travel from one end to the other of one block section B4 is obtained.
As described above, when the own train 11A travels over a plurality of block sections, the measurement time with higher accuracy can be obtained by adding the times measured in the respective block sections, and the average speed of the preceding train 11B can be more accurately predicted.

(Modification 2)

FIG. 11 is a flowchart illustrating Modification 2. In Modification 2, a measurement does not end halfway through a timing in the case of passing through a block section, and a measurement by the measurement unit 101 is performed over a continuous block section. Therefore, in Modification 2, FIG. 11 is used instead of FIG. 8 among the flowcharts in FIGS. 7 and 8 described above. FIG. 11 is obtained by deleting steps S302 and S303 in the flowchart in FIG. 8 and adding step S302B. As the other processing is the same as in the case of FIG. 8, different part in control will be described below. The description will be given with reference to FIGS. 5 and 6.
The timing by the measurement unit 101 is started at the time t11 when the preceding train 11B moves from the block section B3 to the block section B4 in FIG. 6. When the own train 11A leaves the block section B2 at the time t12 in FIG. 6, the processing proceeds from step S301 to step S302B in FIG. 11. In step S302B, the on-board control unit 100 acquires indication information from the camera 110. An indication recognized by the camera 110 changes from a caution indication to a stop indication at the time t12, and thus the stop indication is stored in the first memory, and the caution indication is stored in the second memory.
When the processing in step S302B ends, the processing proceeds to step S304, and the indication information is acquired again. As a result, both data in the first memory and data in the second memory are a stop indication, and it is determined in step S305 that the indication does not change (N). That is, when the own train 11A moves to the block section B3 at the time t12, processing proceeds in order of step S301, step S302B, step S304, step S305, and step S301. From the time t12 to the time t13, processing in order of step S301, step S304, step S305, and step S301 is repeated.
At the time t13 in FIG. 6, when the preceding train 11B moves from the block section B4 to the block section B5, an indication of the ground railway signal 124C changes from a stop indication to a caution indication. As a result, the indication recognized by the camera 110 of the own train 11A changes, and thus it is determined in step S305 that the indication changes (Y) and the processing proceeds in order of step S306 and step S307, where the timing by the measurement unit 101 ends. A measurement time at this time is t13 - t11, which means that a time during which the preceding train 11B travels through the block section B4 is measured. Therefore, an average speed in step S310 can be accurately calculated.
In the example illustrated in FIG. 6, the time measurement by the measurement unit 101 is performed over the two block sections B2 and B3. However, the time measurement may be performed over more than two block sections. For example, as illustrated by the own train 11A indicated by the dashed line in FIG. 5, the own train 11A is on-rail of the block section B3, not the block section B2, at the time t13.
In this case, when the own train 11A passes through the block section B2, the processing proceeds from step S301 to step S302B in FIG. 11, indication information is acquired in step S302B, the stop indication is stored in the first memory, and the caution indication is stored in the second memory. Thereafter, when the indication information is acquired in step S304, the data in the first memory and the data in the second memory are all stop indications. As a result, processing in order of step S301, step S304, step S305, and step S301 is repeated until the time t13 when the preceding train 11B passes through the block section B4 and the ground railway signal 124C changes to the caution indication.
At the time t13 in FIG. 5, when the preceding train 11B moves from the block section B4 to the block section B5, the processing proceeds in order of step S305, step S306, and step S307, and the timing by the measurement unit 101 ends. That is, the time measurement by the measurement unit 101 is performed over three block sections from the block section B1 to the block section B3, and the measurement time (t13-t11) is obtained.
Further, specific modifications (alternative examples) are given below, and the invention may further combine these modifications. For example, a sign indicated by a clerk may be used instead of the ground railway signal. The on-board control device may learn, for each time of year, day of the week, time period, and operating section, an optimal operation pattern from past operation records to reduce a reduction in operation interval and a reduction in delay increase when a delay occur, store the learning in the database, and select the optimal operation pattern from a prediction range based on the learned result when conditions such as a date and time and an average speed prediction of a preceding train match.
According to the embodiment and the modifications of the invention described above, the following advantageous effects are achieved.
(C1) As illustrated in FIGS. 1 to 8 and the like, the train control system 10 is the train control system 10 to be installed on the train 11 that moves along a predetermined route (the line 121) and control the train 11. The train control system 10 includes: the position acquisition unit 112 configured to acquire an on-rail position of the train 11; the database 111 configured to store a plurality of operation patterns, a relationship between a signal indication of a ground railway signal and a speed limit, and a plurality of ground railway signals 124 and a plurality of block sections on the line 121; the camera 110 configured to image a ground railway signal of a block section on the on-rail position and output indication information; and the on-board control unit 100 configured to calculate, based on the speed limit corresponding to the indication information, the travel permission position 123 and a travelable route 120 that enables traveling to the travel permission position 123, and control traveling of the train 11 based on the travel permission position 123 and the travelable route 120. The on-board control unit 100 includes the measurement unit 101 that measures, when an indication of the indication information changes to an indication other than traveling, a time interval (a measurement time) from a time of the change to a time when the indication of the indication information changes again, the search unit 103 configured to search, based on the indication information during the measurement, the database 111 for a block section where a preceding train is on-rail, and the calculation unit 102 configured to predict an average speed of the preceding train based on the measurement time by the measurement unit 101 and the block section searched by the search unit 103. Traveling of the train 11 is controlled based on the average speed predicted by the calculation unit 102.
In this way, the average speed of the preceding train is predicted based on a time from when the indication information changes to when the indication of the indication information changes again, and the block section where the preceding train is on-rail. Therefore, the traveling of the own train 11A can be controlled based on the predicted average speed of the preceding train 11B such that an operation interval between the own train 11A and the preceding train 11B is not shortened, for example.
(C2) In the above (C1), as illustrated in FIGS. 1 to 8 and the like, the on-board control unit 100 selects, based on the predicted average speed, an operation pattern capable of reducing a reduction in operation interval with the preceding train from the plurality of operation patterns stored in the database 111, and changes an operation pattern of the own train 11A to the selected operation pattern (steps S303 and S311). As a result, the own train 11A can be prevented from getting too close to the preceding train 11B, thereby preventing the operation interval from being shortened.
(C3) In the above (C1), as illustrated in FIGS. 5 to 8 and the like, the on-board control unit 100 predicts the average speed of the preceding train 11B based on the measurement time measured during traveling in a block section where the own train 11A is on-rail. For example, the measurement unit 101 on the own train 11A illustrated in FIG. 5 starts timing at the time t12 when the own train 11A enters the block section B2, and ends the timing at the time t13 while the own train 11A is on-rail of the same block section B2 due to an indication change of the ground railway signal 124B. Then, the calculation unit 102 calculates the average speed of the preceding train 11B based on the obtained measurement time and a distance of the block section B4 through which the preceding train 11B travels.
(C4) In the above (C1), as illustrated in FIGS. 1, 7, 8, and the like, the on-board control unit 100 determines, based on the database 111, whether the ground railway signal 124 imaged by the camera 110 is a ground railway signal whose signal indication always changes when entering a block section. When it is determined that the ground railway signal is a ground railway signal whose signal indication always changes, the on-board control unit 100 restarts a measurement operation by the measurement unit 101 from beginning. When the indication change of the railway signal such as a home railway signal is used as start and end conditions for timing when predicting the average speed of the preceding train, an erroneous determinations is made, and thus as in steps S205 and S306, when it is determined that the ground railway signal is a ground railway signal whose signal indication always changes, the control ends, and then the control is started again to restart the measurement operation from the beginning.
(C5) In the above (C1), as illustrated in FIGS. 1, 6, 9, 10, and the like, when continuity is recognized in two measurement times (t12 - t11) and (t13 - t12) measured for the respective two consecutive block sections B2 and B3, the on-board control unit 100 adds up the two measurement times (t12 - t11), (t13 - t12) obtained for the two consecutive block sections B2, B3, and the calculation unit 102 predicts the average speed of the preceding train 11B based on the result of the addition. In this way, by adding up the two measurement times obtained in the two consecutive block sections B2 and B3, the average speed of the preceding train 11B can be predicted with higher accuracy.
(C6) In the above (C1), as illustrated in FIGS. 1, 6, 7, 11 and the like, the on-board control unit 100 causes the measurement unit 101 to measure the time interval until the indication change while excluding a change in indication of the indication information before and after the own train 11A passes through a block section. In Modification 2, by adopting the processing from step S301 to step S305 in FIG. 11, for example, the indication change before and after the time t12 in FIGS. 5 and 6 is not recognized as an indication change, and is excluded from the indication changes for the time measurement. Thus, the time measurement by the measurement unit 101 is performed over a plurality of block sections, and the time measurement can be performed with higher accuracy.
(C7) In the above (C2), as illustrated in FIGS. 1, 6 to 8, and the like, the on-board control unit 100 selects a highest average speed from the plurality of average speeds predicted by the calculation unit 102 while the own train 11A is moving along the route, and selects, based on the selected highest average speed, the operation pattern capable of reducing a reduction in operation interval with the preceding train 11B. By selecting the average speed prediction value under highest speed conditions from within a predictable range, a delay caused by changing the operation pattern based on an erroneous determination due to variations in prediction accuracy can be prevented.
(C8) As illustrated in FIGS. 1 to 8 and the like, a control method for a train that moves along a predetermined route includes: measuring, when an indication of indication information of a ground railway signal in a block section where the own train 11A is on-rail changes to an indication other than traveling, a time interval from a time of the change to a time when the indication of the indication information changes again (steps S204 to S307), searching, based on the indication information during the measurement, the database 111 storing a plurality of block sections on the route for a block section where the preceding train 11B is on-rail, and predicting an average speed of the preceding train 11B based on the time interval and the searched block section (step S310), and controlling traveling of the own train 11A based on the predicted average speed (step S311).
As a result, the traveling of the own train 11A can be controlled based on the predicted average speed of the preceding train 11B such that the operation interval between the own train 11A and the preceding train 11B is not shortened, for example.
The embodiments and the various modifications described above are merely examples, and the invention is not limited thereto as long as features of the invention are not impaired. Various changes and modifications can be made to those skilled in the art within the scope of the technical idea disclosed in the invention, and various modifications are included. The embodiment described above is given to describe the invention in an easy-to-understand manner, and the invention is not necessarily limited to including all the described configurations. Further, another configuration can be added to, deleted from, or replaced with a part of a configuration of each embodiment.

Reference Signs List

10 train control system
11 train
11A own train
11B preceding train
100 on-board control unit
101 measurement unit
102 calculation unit
103 search unit
110 camera
111 database
112 position acquisition unit
120, 120A, 120B travelable route
121 line
122 arrival station
123, 123A, 123B travel permission position
124, 124A to 124E ground railway signal
125, 125A, 125B speed limit
126, 126A, 126B travel trajectory
B1 to B5 block section

Claims

A train control system to be installed on a train that moves along a predetermined route and control the train, the train control system comprising:
a position acquisition unit configured to acquire an on-rail position of the train;

a database configured to store a plurality of operation patterns, a relationship between a signal indication of a ground railway signal and a speed limit, and a plurality of ground railway signals and a plurality of block sections on the route;

a camera configured to image a ground railway signal in a block section on the on-rail position and output indication information; and

an on-board control unit configured to calculate, based on the speed limit corresponding to the indication information, a travel permission position and a travelable route that enables traveling to the travel permission position, and control traveling of the train based on the travel permission position and the travelable route, wherein

the on-board control unit includes
a measurement unit that measures, when an indication of the indication information changes to an indication other than traveling, a time interval from a time of the change to a time when the indication of the indication information changes again,

a search unit configured to search, based on the indication information during the measurement, the database for a block section where a preceding train is on-rail, and

a prediction unit configured to predict an average speed of the preceding train based on the time interval and the block section searched by the search unit, and

traveling of the train is controlled based on the average speed predicted by the prediction unit.
The train control system according to claim 1, wherein
the on-board control unit selects, based on the average speed, an operation pattern capable of reducing a reduction in operation interval with the preceding train from the plurality of operation patterns stored in the database, and

changes an operation pattern of the train to the selected operation pattern.
The train control system according to claim 1, wherein
the on-board control unit predicts the average speed based on the time interval measured during traveling in a block section where the train is on-rail.
The train control system according to claim 1, wherein
the on-board control unit further includes a determination unit configured to determine, based on the database, whether the ground railway signal imaged by the camera is a ground railway signal whose signal indication always changes when entering a block section, and

when the determination unit determines that the ground railway signal is a ground railway signal whose signal indication always changes, the on-board control unit restarts a measurement operation by the measurement unit from beginning.
The train control system according to claim 1, wherein
the on-board control unit further includes an adding unit configured to add up and output, when continuity is recognized in a plurality of the time intervals measured for the respective two or more consecutive block sections, the plurality of the time intervals obtained in the two or more consecutive block sections, and

the prediction unit predicts the average speed based on output of the adding unit.
The train control system according to claim 1, wherein
the on-board control unit causes the measurement unit to measure the time interval while excluding a change in indication of the indication information before and after the train passes through a block section.
The train control system according to claim 2, wherein
the on-board control unit selects a highest average speed from a plurality of the average speeds predicted by the prediction unit while the train is moving along the route, and selects, based on the selected highest average speed, the operation pattern capable of reducing a reduction in operation interval with the preceding train.
A train control method for a train that moves along a predetermined route, the train control method comprising:
measuring, when an indication of indication information of a ground railway signal in a block section where the train is on-rail changes to an indication other than traveling, a time interval from a time of the change to a time when the indication of the indication information changes again;

searching, based on the indication information during the measurement, a database storing a plurality of block sections on the route for a block section where a preceding train is on-rail;

predicting an average speed of the preceding train based on the time interval and the searched block section; and

controlling traveling of the train based on the predicted average speed.