WO2006136783A1

WO2006136783A1 - Safety arrangement

Info

Publication number: WO2006136783A1
Application number: PCT/GB2006/002137
Authority: WO
Inventors: Coenraad Jacobus Groenewald
Original assignee: Coenraad Jacobus Groenewald
Priority date: 2005-06-22
Filing date: 2006-06-13
Publication date: 2006-12-28
Also published as: GB0512667D0

Abstract

A safety arrangement is provided for a train operating on a rail network (10). A Global Positioning System (GPS) receiver (27) is installed at the front of the train (26), and another separately identifiable GPS receiver (28) is installed at the rear of the train (26). The GPS receivers (27, 28) are operable to detect the identity, continuous time position, direction and speed of the train (26) within a rail network (10). The GPS receivers (27, 28) are also operable to transmit that data, encrypted and coded, to a control centre (40) and/or to other trains within that rail network (10). A signal indicator (35) in the train (26) is operable to display a signal when the train (26) is within a predetermined distance of a detectable item along the planned route, and waypoint devices (21, 22, 23) are located upstream and downstream of strategic positions (13, 16, 19, 20) along the rail network (10). The waypoint devices (22) are operable to signal to a GPS receiver (27) installed in a train (26) the configuration of facing points (16, 19, 20) that are within a predetermined distance. A mast or beacon system (34) is disposed around the rail network (10) and operable to detect the position of the train (26) when the GPS signal is interrupted.

Description

SAFETY ARRANGEMENT

This invention relates to safety arrangements, and in particular to arrangements for ensuring the safety of trains operating on a rail network.

Currently trains are controlled by means of signals disposed adjacent the rail tracks. The signals permit train movements past the signals by displaying Proceed Aspects in either 2- aspect, 3-aspect or 4-aspect signalling configurations. A signal displaying a Red Aspect may not be passed by a train under normal conditions. A Yellow aspect is displayed when the next signal ahead is Red and the train has at least also cleared the required overlap past the signal at Danger. Signals are placed at minimum distances apart, determined by the braking ability and allowable speed of different train-sets, as mandated by the Health and Safety Executive/Commission (HSE/C), through the Railway Safety & Standards Board (RSSB) standards in the U.K. Signal spacing is also dependant on the gradient of the line and varies between 165m at 20mph (32kph) on a 1 in 50 (2%) rising gradient, to 3312m on 1 in 50 (2%) falling gradient. The positions of the trains in a sector of the rail network are detected by means of devices such as Track Circuits, and used in what is termed Fail-safe operational mode. This means that the Track Circuit Relay is normally energised (front contacts making), and fails to the de-energised position. Different types of equipment detect different lengths of track, as specified by the individual manufacturers. Required detection lengths for Block sections are obtained by serially combining the pick-up of Repeat Relays. The proving of the presence or absence of a train is used in the Signalling Control Circuitry. The positions of the trains in a control area are displayed on illuminated diagrams at a control centre or signal box. Less costly Track Circuits require costly Insulated Rail Joints (IRJs) to isolate track circuit sections, and Frequency modulated Track Circuits, which do not require IRJs, are more expensive.

However, the driver of a train may not react properly to the signals for any one of a number of reasons, and this results in trains passing signals at danger, events known as SPADs (signal passed at danger), sometimes with catastrophic results, if the overrun of the train is in a conflict area. If a Train Protection & Warning System (TPWS) is fitted and a train approaches a signal where a conflict can occur, a sensor will determine the train speed and reduce that speed. This is done by energising an electro-magnet between the rails, which applies the brakes of the train to reduce its speed. If the speed is then not reduced further by the driver, a final sensor in advance of the signal will measure this and stop the train, effective to 75mph. The present Signalling Control and Detection System is outdated, costly to maintain and places a heavy burden on the authorities to develop and implement new railway infrastructure, and many lines are left disbanded with infrastructure still reasonably sound. Trackside equipment is expensive to install and even more expensive to maintain. Equipment is expensive, trackside housing e.g. Location cases and Relocatable Equipment Buildings (REBs) have to be provided, power has to be provided at these remote locations, and the control and indication functions have to be provided through cables or by Remote Control.

To improve on the present arrangements, and to overcome or at least further minimise the risk of SPADs, left by the present TPWS equipment, the authorities have proposed to introduce the European Rail Transport Management System (ERTMS) to level 2. This system is under test on a section of the Cambrian Coast lines and will display the aspect of the signals ahead in the driver's cab of each train, instead of at the track side. It is envisaged that tests will be completed by 2008 and if accepted, this system will overcome the problem of signal positioning and visibility and will reduce considerably maintenance on trackside equipment, but will not eliminate it. In some countries, an alternative system is the European Train Control System (ETCS).

It is an object of the present invention to provide a safety arrangement that is less costly to install and maintain than the above-described arrangements, but which provides at least the equivalent level of safety as the present system. It is a further object to provide a safety arrangement in which the principles are suitable to apply as a stand-alone train control system or alternatively as an interface with existing systems such as Automatic Train Control (ATC), Automatic Train Operation (ATO) as well as the ERTMS to level 3.

The invention provides a safety arrangement for a train comprising a Global Positioning System (GPS) receiver installed in the train, the GPS receiver being operable to detect the identity, continuous time position, direction and speed of the train within a rail network, the GPS receiver being operable to transmit that data to a control centre and/or to other trains within that rail network, and comprising waypoint devices located at strategic positions along the rail network and a signal indicator in the train operable to display a signal when the train is within a predetermined distance of a detectable item along the planned route.

By strategic positions is intended to include points, level crossings and permanent speed restrictions, and may include temporary strategic positions such as temporary work zones. A first waypoint device may be located upstream and a second waypoint device may be located downstream of a strategic position. In the case of points, the waypoint devices may be operable to determine whether the points are in normal (N, route goes straight through) or reverse (R, route diverted to side line) configuration and whether they are locked in such configuration. The waypoint devices may be operable to send to the GPS receiver installed in a train that is within a predetermined distance of facing points a signal responsive to that determination, whereby the GPS receiver may display the configuration of the facing points.

A requirement will be to determine accurately the waypoints of all the running lines (sidings excluded), approximately in the centre of the lines in both directions, if not available already from a system such as Omni-Com through their Omni-Vision. This rail network data includes the configuration of the rail network, the position of all points and level crossings disposed along the running rails of that rail network, and the location and extent of all permanent speed restrictions within that rail network. By detectable item is intended to include another train, a level crossing, points, permanent speed restrictions and/or a temporary work zone.

The GPS receiver may comprise a dual frequency receiver operable to receive selected and alternative frequency signals from the GPS, and the GPS receiver may be operable to transmit selected and alternative frequency signals to control centre and/or to other trains within that rail network. The signals may be encrypted and coded, and may be transmitted on a secure data link, e.g. Global System for Mobile communications - Railways (GSM-R), by using static or intelligent balises, by using routers (on the internet, by satelite or a Local Area Network (LAN), or by Real Time Ethernet (RTE). The safety arrangement may comprise a GPS receiver installed at the front of the train, and may comprise a second GPS receiver installed at the rear of the train. In this case, the GPS receivers may be separately identifiable.

The safety arrangement may comprise speed detection means installed in the train and onboard programmable means operable to calculate the distance travelled by the train since the last GPS position detected and control the speed of the train. The safety arrangement may comprise a mast or beacon system disposed around the rail network and operable to detect the position of the train when the GPS signal is interrupted.

The safety system may comprise braking means operable to stop both sections of a train if the distance between the GPS receivers at the front and rear of the train increases significantly due to the sections of the train becoming separated.

The invention will now be described with reference to the accompanying drawings in which: Fig. 1 is a schematic diagram of waypoints along a section of rail network, Fig. 2 is a schematic diagram of the GPS and a train on the rail network, and Fig. 3 is a schematic diagram of several trains on the rail network.

Referring now to Fig. 1 , there is shown a section of a rail network 10 having a normally up line 11 and a normally down line 12, as shown by the arrows UL, DL Also shown is a level crossing 13 and cross-over lines 14, 15. The cross-over lines 14, 15 are controlled by points 16. The rail network 10 also includes no. 1 and no. 2 loops or sidings 17, 18 controlled by respective points 19, 20. Upstream and downstream of the level crossing 13 on both normally up line 11 and a normally down line 12 are located waypoint devices 21. Waypoint devices 22 are located to the facing side of the points 16 of each cross-over line 14, 15, and waypoint devices 23 are located at the clearance region to the trailing side of points 16 on the running lines. The waypoint devices 22, 23 are operable to detect whether the points 16 are lying normal (N) or reverse (R), whether they are locked in such disposition, and that the points 16 at both ends of a cross-over line 14, 15 are in the same configuration and locked. If, as shown in Figure 1 , a Train Protection & Warning System (TPWS) is fitted and a train approaches a strategic position, e.g. level crossing 13, points 16, 19, 20, or workers 25, where a conflict or dangerous situation can occur, a sensor 24 will determine the train speed and reduce that speed. This is done by energising an electro-magnet between the rails 11 , 12, which applies the brakes of the train to reduce its speed. If the speed is then not reduced further by the driver, a second final sensor 24 in advance of the strategic position will measure this and the brakes will be applied to stop the train, effective to 75mph. Alternatively, in the case of the train approaching another train on the same line, or a speed limit section, the on-board computer 30 (Fig. 2) will, based on the distance (headway) from the other train/section, the train speed and line gradient, slow the train to maintain the acceptable headway to the other train or to the acceptable speed in the speed limit section in an ongoing real time mode.

Referring now to Fig. 2, there is shown a train 26 on the line 11 of the rail network 10. Dual frequency GPS receiver 27 is installed at the front and dual frequency GPS receiver 28 is installed at the rear of the train 24. Each receiver 27, 28 has a GPS aerial 29 and is coupled with a respective on-board computer 30. The aerials 29 receive selected and alternative frequency signals from the Navstar GPS constellation 31 , the Glonass GPS constellation 32 and/or the Egnos GPS augmentation system constellation 33. The aerials 29 may also receive signals from fixed masts or beacons 34 located alongside the rail network 10. This is particularly important if the GPS signals are interrupted for any reason, e.g. weather conditions or the train 26 is in a tunnel. The GPS receivers 27, 28 are separately identifiable, and are operable to detect the identity, continuous time position to within sub-1 metre accuracy, direction and speed of the front and rear respectively of the train 26 within the rail network 10, and are programmed with the rail network data. This ensures the front and rear GPS receivers 27, 28 maintain a constant separation and that there is no severance of connection between the front and rear of the train 26. If the separation increases, the safety system is operable to apply the brakes (not shown) to both sections of the train 26. In this way, the integrity of the train 26 is ensured. A signal indicator 35 in the train 26 is operable to display a signal when the train 26 is within a predetermined distance of a detectable item along the planned route. The detectable item may be another train ahead on the same line that is closer than is allowable, a level crossing, points and/or a temporary work zone. The waypoint devices 22 are operable to send to the front GPS receiver 27, when train 26 is within a predetermined distance of facing points 16, a signal responsive to that determination, whereby the front GPS receiver 27 can display the configuration of the facing points 16. In the event that the GPS signals are interrupted, a speed measuring device 36 provides that the computer 30 can calculate the speed of the train 26, the distance travelled since the last GPS position determination, and hence the current position of the train 26.

Referring now to Fig. 3, there are shown three trains 37, 38, 39 spaced along the rail track 11. The GPS receivers/computers 27, 28, 30 in the front and rear of each train 37, 38, 39 receive GPS signals as described above. A control centre 40 also receives signals from each train 37, 38, 39 so that the position of each train 37, 38, 39 is known and displayed in the control centre 40. The signals form a secure, encrypted link to identify each train 37, 38, 39 through coded messages to trains ahead 38, 39 and to the rear 37, 38, as well as to the control centre 40. The control centre 40 sends a signal, as train 37 approaches within a predetermined distance of the level crossing 13, to a level crossing controller 41. The level crossing controller 41 activates the level crossing gates, barriers and/or warning signals at that level crossing 13. Similarly, the points 16 ahead of train 38 are changed by points controller 42 as necessary so that the train 38, which is the next train to reach those points 16, is directed along the correct route, i.e. branch line 17 or main line 11.

In principle the safety arrangement of the present invention is to replace the current track- based Train Detection equipment with a Global Positioning aided Train Detection System, and apply the continuous updated information of the position of the train; to replace the present "Fixed Block System" of train control with advanced "Moving Block" Principles", to create the ability to apply more flexibility in train control and running times, without sacrificing the present inherent and required fail-safe principles, but rather enhancing them. Dependant on the requirement of the client, this safety arrangement will be suitable for applying to a stand-alone train control system, or alternatively as an interface with existing systems such as Automatic Train Control (ATC), Automatic Train Operation (ATO) and the European Rail Transport Management System (ERTMS), up to Level 3, or the European Train Control System (ETCS) to replace the existing train detection methods. The system of the present invention is designed to conform with U.K. regulations, but may be modified if necessary to conform with International regulations. Some advantages: a) Sub-one metre accuracy can be attained by Augmenting GPS signals of American Navstar and/or Russian Glonass constellations. b) Further augmentation can be attained by applying Beacon, Geo-stationary satellite or Egnos signals to Navstar and/or Glonass signals. c) Wide Area Augmentation (WAAS) and Local Area Augmentation (I-AAS) principles can be applied as required by tests to be undertaken. d) All level crossings, irrespective of whether gates or barriers are fitted, can be operated inexpensively with the same degree of safety required, at a fraction of the present cost, with a much better time-control to close and subsequently operate the gates, barriers and/or warning systems. e) Existing but unused lines may be brought into use without the large cost of updating current signalling systems and trackside equipment. f) Temporary speed restrictions can be readily put in place, e.g. at work zones, and subsequently removed, considerably quicker and at much less cost than at present.

Claims

1. A safety arrangement for a train comprising a Global Positioning System (GPS) receiver (27) installed in the train (26), the GPS receiver (27) being operable to detect the identity, continuous time position, direction and speed of the train (26) within a rail network (10), the GPS receiver (27) being operable to transmit that data to a control centre (40) and/or to other trains within that rail network (10), characterised by waypoint devices (21 , 22, 23) located at strategic positions (13, 16, 19, 20) along the rail network (10), and by a signal indicator (35) in the train (26) operable to display a signal when the train (26) is within a predetermined distance of a detectable item along the planned route.

2. A safety arrangement as claimed in claim 1 , characterised in that a first waypoint device (21 , 22) is located upstream and a second waypoint device (21 , 23) is located downstream of a strategic positionθ 13, 16, 19, 20).

3. A safety arrangement as claimed in claim 2, characterised in that, in the case of points (16, 19, 20), the waypoint devices (22, 23) are operable to determine whether the points (16, 19, 20) are in normal (N, route goes straight through) or reverse (R, route diverted to side line) configuration and whether they are locked in such configuration.

4. A safety arrangement as claimed in any one of claims 1 to 3, characterised in that waypoint devices (22) are operable to send to the GPS receiver (27) installed in a train (26) that is within a predetermined distance of facing points (16, 19, 20) a signal responsive to that determination.

5. A safety arrangement as claimed in claim 4, characterised in that the GPS receiver (27) is operable to display the configuration of the facing points (16, 19, 20).

6. A safety arrangement as claimed in any one of claims 1 to 5, characterised in that the GPS receiver (27) comprises a dual frequency receiver operable to receive selected and alternative frequency signals from the GPS.

7. A safety arrangement as claimed in any one of claims 1 to 6, characterised in that the GPS receiver (27) is operable to transmit selected and alternative frequency signals to control centre (40) and/or to other trains within that rail network (10).

8. A safety arrangement as claimed in claim 7, characterised in that the signals are encrypted and coded.

9. A safety arrangement as claimed in claim 8, characterised in that the signals are transmitted on a secure data link.

10. A safety arrangement as claimed in claim 9, characterised in that the signals are transmitted on a Global System for Mobile communications - Railways (GSM-R).

11. A safety arrangement as claimed in any one of claims 1 to 10, characterised by a GPS receiver (27) installed at the front of the train (26).

12. A safety arrangement as claimed in claim 11 , characterised by a second GPS receiver (28) installed at the rear of the train (26).

13. A safety arrangement as claimed in claim 12, characterised in that the GPS receivers (27, 28) are separately identifiable.

14. A safety arrangement as claimed in any one of claims 1 to 13, characterised by speed detection means (36) installed in the train (26).

15. A safety arrangement as claimed in claim 14, characterised by on-board programmable means (30) operable to calculate the distance travelled by the train (26) since the last GPS position detected and control the speed of the train (26).

16. A safety arrangement as claimed in any one of claims 1 to 15, characterised by a mast or beacon system (34) disposed around the rail network (10) and operable to detect the position of the train (26) when the GPS signal is interrupted.

17 A safety arrangement as claimed in claim 13, characterised by braking means operable to stop both sections of a train (26) if the distance between the GPS receivers (27, 28) at the front and rear of the train (26) increases significantly due to the sections of the train (26) becoming separated.

18. A safety arrangement substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.