GB2572993A

GB2572993A - Rail safety method and apparatus

Info

Publication number: GB2572993A
Application number: GB1806360.2A
Authority: GB
Inventors: Hardy Christopher
Original assignee: Siemens Rail Automation Holdings Ltd
Current assignee: Siemens Mobility Ltd
Priority date: 2018-04-19
Filing date: 2018-04-19
Publication date: 2019-10-23
Anticipated expiration: 2038-04-19
Also published as: GB2572993B; GB201806360D0

Abstract

A rail safety method involves the steps of acquiring a physical parameter of a train (such as length or weight) based on train characteristic information reported by the train; measuring a true physical parameter of the train; comparing the true physical parameter to the acquired physical parameter and generating an alarm signal if they are different. An apparatus for implementing the method uses an external sensor 10,11 (such as a photo-electric sensor, an axle counter, track circuit sections, or a weighbridge) to measure the true physical parameter, and a comparison engine 14. The train characteristic information is determined according to data input by an operator of the train, or from a train on-board sensor. Measuring the true length of the train may involve measuring the train speed and time taken to pass a point. The train may be automatically stopped if the parameters are different or outside of an acceptable range. The alarm signal may cause an alarm to transmit to a display in the train or a control system; and update the train characteristic information.

Description

Rail Safety Method and Apparatus

The present disclosure relates to rail safety methods and to rail safety apparatus. In particular the disclosure is concerned with a rail safety method and apparatus useful in proper operation of communication-based signalling systems.

Background

As increasing levels of information technology and system automation are brought into railway operation, it becomes important that safety critical systems are given accurate data to work from. Otherwise, potentially dangerous errors in signalling, train operating speed etc. may occur. Methods and apparatus that improve safety performance of such systems are thus highly desirable.

Summary

According to the present disclosure there is provided a method and apparatus as set forth in the appended claims. Other features of the invention will be apparent from the dependent claims, and the description which follows.

Accordingly there may be provided a rail safety method comprising: acquiring a physical parameter of a train based on train characteristic information reported by the train; measuring a true physical parameter of the train; comparing the true physical parameter of the train with the acquired physical parameter of the train; and generating an alarm signal based on the comparison if the true physical parameter of the train and the acquired physical parameter are different.

In this way, communication-based signalling systems or other safety critical systems that rely on accurate reporting of a train's physical parameters can operate to protect against errors, based on the alarm signal. Safety can be improved in the case of inaccurate information being reported by the train, for example inaccurate information resulting from erroneous data entry by a train operator.

In one example the train characteristic information is determined according to data input by an operator of the train, such as via a Driver Machine Interface. In one example the train characteristic information is determined according to data from an on-board sensor of the train. In one example the train characteristic information is reported when the train is initialised prior to a journey.

In one example the generating an alarm signal based on the comparison takes place during a journey. In one example the generating an alarm signal based on the comparison takes place before, or at a point when the train passes onto a line on which the true physical parameter is used for safety purposes, for example onto a line on which the true physical parameter is used by a communication-based signalling system on the line. In one example the method is performed as part of, or in conjunction with operating the train under a communication-based signalling system. In one example the communication-based signalling system is the European Train Control System.

In one example the physical parameter of the train is length. In one example the step of measuring the true length of the train comprises at least one selected from a group comprising: measuring a speed of the train and a time taken for the train to travel past a fixed point; detecting axles passing by multiple axle counters; determining track occupancy information from multiple more track circuit sections.

In one example the step of measuring the true length of the train comprises measuring a speed of the train and a time taken for the train to travel past a fixed point, and the true length of the train is measured from a first detected extremity of the train to the last detected extremity of the train as it passes the fixed point.

In one example the physical parameter of the train is weight.

In one example the method further comprises the step of automatically stopping the train if the true physical parameter of the train and the acquired physical parameter are different.

In one example the method comprises determining if the true physical parameter, although determined to be different to the acquired physical parameter, is within an acceptable range for safe operation of the train according to expected behaviour for trains with the true physical characteristic corresponding to the different acquired physical characteristic. In this case the alarm signal may be used for information only, and operation of the train may take place as normal.

In one example the method further comprises the step of outputting an alarm based on the generated alarm signal. In one example the method comprises outputting an alarm based on the generated alarm signal by transmitting the alarm to a control system; outputting the alarm to an operator of the train; and outputting the alarm to an operator of the control system.

In one example the method comprises the step of updating the train characteristic information, in response to the generated alarm signal. In one example the method comprises updating the train characteristic information to that of a train matching the true physical parameter as measured. In this way, accurate train characteristic information may be generated and stored for future use, allowing the train to operate normally thereafter, even if incorrect information had been originally entered by a train operator.

In one example the method comprises logging the true physical parameter of the train and/or the acquired physical parameter of the train, on generation of the alarm signal. In this way, the logged data may be used for accuracy reporting purposes, and subsequent operational process improvement.

Accordingly there may be provided a rail safety apparatus comprising: a sensor external to a train, configured to measure a true physical parameter of the train; and a comparison engine configured to compare the true physical parameter of a train acquired from the sensor with a physical parameter acquired based on train characteristic information reported by the train, and to generate an alarm signal if the true physical parameter of the train and the acquired physical parameter are different.

In one example the apparatus comprises an operator data input unit operable to receive train characteristic information from an operator. In one example the apparatus comprises an on-board sensor for reporting the characteristic information, for example a train length sensor and/or a train weight sensor.

In one example the sensor comprises a photoelectric sensor. In one example the sensor comprises a plurality of axle counters. In one example the sensor comprises a plurality of track occupancy circuits. In one example the sensor comprises a weighbridge.

In one example the apparatus is arranged to provide the alarm signal to output device to alert the operator of the train. In one example the apparatus is arranged to provide the alarm signal to a control system. In one example the apparatus is arranged to provide the alarm to an operator of a control system, such as a signalling control system. In one example the signalling control system is a communication-based train control system, such as the European Train Control System.

In one example the apparatus comprises a feedback path for updating the train characteristic information, in response to the generated alarm signal of the comparison engine. In one example the comparison engine is configured to update the train characteristic information to that of a train matching the true physical parameter as measured.

Brief Description of the Drawings

Examples of the present disclosure will now be described with reference to the accompanying drawings, in which:

Figure 1 shows a schematic overview of a rail safety apparatus according to an example embodiment in use with a train and a railway control system; and

Figure 2 is flow diagram illustrating steps in a rail safety method according to an example embodiment.

Detailed Description

Figure 1 shows a schematic overview of a rail safety apparatus according to an example embodiment in use with a train 1 and a railway control system 20.

The rail safety apparatus comprises a length sensor 10, external to the train 1, configured to measure the true length of the train 1 as the train 1 moves along the track 2. In this example embodiment the rail safety apparatus further comprises a weight sensor 11 that operates by measuring the load imparted on the track 2 as the train 1 moves along the track 2. The length sensor 10 is conveniently provided by a photoelectric or other beam-breaking sensor that can determine the start and end times of passing of the train 1 to determine the length of the train 1, and can separately measure the speed of the train 1 in order to calculate the true length of the train 1. The raw output of the sensors 10, 11 is fed to an evaluation unit 12 which is programmed to generate the corresponding true physical parameters of length and weight of the train 1.

In addition to generation of the true physical parameters based on the measurements taken by the sensors 10, 11 as described, the train 1 is arranged to provide train characteristic information based on data collected on-board. The train characteristic information is used to acquire physical parameters of the train. For example characteristic information provided via an operator data input unit such as via a Driver Machine Interface (not shown). The train operator initialises the train 1 prior to driving the train 1 along the track 2. In doing so the operator may provide data on the train length and weight directly, or indirectly by choosing from a list of train characteristics from which the length and weight can be derived. For example the operator may initialise the train 1 and in doing so confirm that the train 1 is operating as a single three-car set, or a combination of more than one sets, each of which has known length and weight.

The train characteristic information and/or physical parameters based thereon are reported by the train 1 to a trackside signalling system 18 over a wireless network 16. The trackside signalling system 18 and evaluation unit 12 pass the respective characteristics to a comparison engine 14. The comparison engine 14 compares the true physical parameters acquired from the sensors 10, 11 with the physical parameters acquired based on the train characteristic information reported by the train. The comparison engine 14 is arranged to generate an alarm signal if the true physical parameters of the train and the acquired physical parameters are different.

The alarm signal is passed to a control system 20 for processing. The control system 20 logs the alarm signal in its system log 21 and raises a visible alarm on a display 22 so that a control system operator can determine appropriate action. Although not shown, there may be a communication path back through the trackside signalling system 18 so that the alarm signal can be passed to the train 1 to stop the train, or to alert the operator of the train 1, or to take other action. For example there may be a feedback path that enables the train characteristic information stored by the train to be updated based on the measured physical characteristic, according to a known relationship between these pieces of data. Further operational improvements may be obtained by later examining aggregated logged data that includes the parameters that led to previous alarm signals being generated. In this way, issues with operator training or systematic errors leading to incorrect data generation may be identified and corrected.

In other embodiments the acquired physical parameters are derived from train characteristic information directly measured by on-board sensors of the train as an alternative, or in addition to the train characteristic information input by an operator. In such cases, although operator error should not lead to misreporting of the physical parameters, the use of the comparison engine to verify the parameters increases the safety integrity level by providing a check on proper operation of the on-board sensors.

Figure 2 is flow diagram illustrating steps in a rail safety method according to an example embodiment. At step S101 a physical parameter of a train is acquired based on train characteristic information reported by the train. The train may in this example report via to a trackside signalling system, based on data input by an operator when the train is initialised. At step S102 a true physical parameter of the train is measured. At step S103 the true physical parameter of the train is compared with the acquired physical parameter of the train and an alarm signal is generated based on the comparison if the true physical parameter of the train and the acquired physical parameter are different.

As will be appreciated, the step of generating an alarm signal may be followed by the subsequent step of outputting an alarm based on the generated alarm signal. Suitably, the alarm may be output to an operator of the train and to an operator of the control system that is responsible for monitoring train safety. The generated alarm signal may also be used in automatic safety override functions, such as to automatically stop the train. The true physical parameters and acquired parameters may be different from one another, but within an acceptable error range that does not impact on safe operation of the train at a given point on the line. In this situation the generated alarm signal may be used for information only, and other operation of the train may take place as normal.

The step S103 may be performed so that the alarm signal is generated only at the point when the train passes on to a part of the line where the true physical parameter is used for safety purposes, or where the difference between true physical parameters and acquired parameters is relevant to safety. For example, on a line controlled under a communication-based signalling system the true physical parameter is used by the signalling system, and therefore incorrect reporting of the train's characteristics, outside of the permitted tolerances, becomes a safety issue.

In another embodiment, the generated alarm signal may be a prompt to manually, or automatically update the train characteristic information with correct data. For example, if the train characteristic information indicates that the train is formed as a three car set but the true length of the train is measured at a length corresponding to six cars, the measured length can be used to determine that the train characteristic information should be updated.

As described above, the example embodiments enable signalling systems or other safety systems that rely on accurate reporting of a train's physical parameters to operate in a manner that reduces problems caused by operator error, leading to an overall improvement in safety.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method 5 or process so disclosed.

Claims

1 A rail safety method comprising:

acquiring a physical parameter of a train based on train characteristic information reported by the train (S101);

measuring a true physical parameter of the train (S102);

comparing the true physical parameter of the train with the acquired physical parameter of the train and generating an alarm signal based on the comparison if the true physical parameter of the train and the acquired physical parameter are different (S103).

2 The method of claim 1, wherein the train characteristic information is determined according to data input by an operator of the train.

3 The method of claim 1 or 2, wherein the train characteristic information is determined according to data from an on-board sensor of the train.

4 The method of any preceding claim, wherein the physical parameter of the train is length.

5 The method of claim 4, wherein the step of measuring the true length of the train comprises at least one selected from a group comprising: measuring a speed of the train and a time taken for the train to travel past a fixed point; detecting axles passing by multiple axle counters; determining track occupancy information from multiple more track circuit sections.

6 The method of claim 5, wherein measuring the true length of the train comprises measuring a speed of the train and a time taken for the train to travel past a fixed point, and the true length of the train is measured from a first detected extremity of the train to the last detected extremity of the train as it passes the fixed point.

7 The method of any preceding claim, wherein the physical parameter of the train is weight.

8 The method of any preceding claim, further comprising the step of automatically stopping the train if the true physical parameter of the train and the acquired physical parameter are different.

9 The method of any preceding claim, further comprising determining if the true physical parameter, although determined to be different to the acquired physical parameter, is within an acceptable range for safe operation of the train, and in this case allowing operation of the train to take place as normal.

10 The method of any preceding claim, further comprising the step of outputting an alarm based on the generated alarm signal, wherein the outputting of the alarm based on the generated alarm signal comprises at least one selected from a group comprising: displaying the alarm on a display device in the train; transmitting the alarm to a control system; outputting the alarm to an operator of the control system.

11 The method of any preceding claim, further comprising the step of updating the train characteristic information, in response to the generated alarm signal.

12 A rail safety apparatus comprising:

a sensor (10, 11) external to a train, configured to measure a true physical parameter of the train; and a comparison engine (14) configured to compare the true physical parameter of a train acquired from the sensor (10, 11) with a physical parameter acquired based on train characteristic information reported by the train, and to generate an alarm signal if the true physical parameter of the train and the acquired physical parameter are different.

13 The apparatus of claim 12, further comprising an operator data input unit operable to receive train characteristic information from an operator of the train.

14 The apparatus of claim 12 or 13, further comprising an on-board sensor for reporting train characteristic information.

15 The apparatus of claim 12, 13 or 14, wherein the sensor external to the train (10, 11) comprises at least one selected from a group comprising: a photoelectric sensor; a plurality of axle counters; a plurality of track circuit sections; and a weighbridge.