WO2010135784A1

WO2010135784A1 - Railroad warning system

Info

Publication number: WO2010135784A1
Application number: PCT/AU2010/000656
Authority: WO
Inventors: Jim Watters
Original assignee: Unit Group Rail Services Limited
Priority date: 2009-05-29
Filing date: 2010-05-28
Publication date: 2010-12-02
Also published as: AU2010251883A8; WO2010135784A8; AU2010251883A1

Abstract

This invention concerns a railroad warning system, and in particular a warning system for a grade crossing. The system may comprise a radio transmitter located on a train, to selectively transmit real-time radio warning signals while the train is in the vicinity of a crossing. And, a radio receiver located in a road vehicle, operable to receive radio warning signals, and relay an audible or visual warning related to the current hazard presented by the train, in the event the vehicle is determined to be approaching the crossing.

Description

Title

Railroad Warning System

Technical Field

This invention concerns a railroad warning system, and in particular a warning system for a grade crossing.

Background Art

Two significant factors in collisions between road and rail vehicles at grade crossings are: failure by road drivers to detect an oncoming train, and if the train is detected, to ignore or not comprehend the risk involved in proceeding across the railway line in the path of an oncoming train

The standard methods of avoiding or mitigating these factors is to establish signage that draws attention to the risk. It is also common to install equipment that detects trains approaching and produces audible and visual warnings of this approach; such as sounding bells and flashing lights.

Warnings are extended in many cases by the activation of barriers or booms that partially or completely prevent access to the rail track for the duration of the hazard.

These methods all require significant equipment to be installed at or near each grade crossing.

Furthermore, in countries like Australia the number of grade crossings is very high compared to rail and road traffic volumes, and the cost of installing conventional fixed equipment at every grade crossing is prohibitive. A large number of crossings, principally in rural areas, are left with static signage only. There are also significant numbers of private and commercial crossings where the conventional fixed systems are not place, but low-level collision risk is incipient.

Disclosure of the Invention

A railroad warning system for grade crossings, comprising

A radio transmitter located on a train, to selectively transmit real-time radio warning signals while the train is in the vicinity of a crossing.

A radio receiver located in a road vehicle, operable to receive radio warning signals, and relay an audible or visual warning related to the current hazard presented by the train, in the event the vehicle is determined to be approaching the crossing.

The radio transmitter may be associated with a satellite positioning system that is able to determine when the train is in the vicinity of the crossing; either when approaching the crossing or leaving the crossing.

The train location information will typically be obtained from a satellite positioning system such as GPS, GLONASS or Galileo. Alternatively, trackside transponders can be used to respond to the train's passing by transmitting a signal to the train containing updated location information. A combination of these techniques may be employed to ensure up to date location information is available when the GPS signal is unavailable.

The radio warning signal may be transmitted when the locomotive approaches the crossing, when it passes the crossing, when it leaves the crossing, or at any combination of these situations.

The radio warning may contain information about the hazard. For instance, the content of the warning may change as the locomotive gets closer to the crossing, and as it gets further away from the crossing. The content of the warning may change depending on a range of factors including the distance of the locomotive from the crossing or the speed of the locomotive, or both. Other factors that might affect the content of the warning may include the length of the train, the type of train, for example good trains, express trains or suburban trains.

The receiver in the motor vehicle may be any suitable receiver. However it is advantageous if the receiver is associated with satellite positioning equipment in the vehicle.

In a simple form of the invention the radio transmitter transmits the radio warning signal with a preselected limited signal strength that determines the range over which the transmission can be properly received. In this case all vehicles that receive the transmission will be determined to be approaching the crossing. Vehicles outside the range will be determined not to be approaching the crossing.

In more complex forms of the invention the radio transmitter may transmit the radio warning to particular road vehicles using a logical address. These vehicles may for instance be those identified to be in a particular length of road. In a refinement they may also be vehicles that are determined to be travelling towards the crossing; rather than away from it. Geofencing techniques may be used for this purpose.

Where the road vehicle has an on board satellite navigation system, the radio reception capabilities of this equipment may be utilized to receive the radio warning signal. Satellite navigation equipment provides a screen display (representation) of the vehicle environs, typically showing the route with salient (other) roads, place names, directional information and points of interest to orient and advise a driver. Some of these systems also provide additional information including traffic and dynamic advisories for immediate driving actions, alternate routes available and time to destination. Points-of-interest can include grade crossings

Where current traffic condition information and dynamic advisories on route changes is provided, these systems require a radio network connection for the navigation equipment for both addressed communications and in some implementations, also to receive broadcast communications.

The radio warning signal may be interpreted by the messaging functionality of the satellite navigation equipment and transmitted from loudspeakers inside the vehicle to warn the driver. However, in more sophisticated forms of the invention the satellite navigation system may be interrogated to determine whether the vehicle is travelling on a road that intersects the crossing, or whether the motor vehicle is travelling towards the crossing, or both; before the determining whether to warn the driver. In this case the visual display of the navigation system may be engaged, in addition or instead of an audible warning. The visual display may be engaged to display a static or moving icon on the road ahead; perhaps as a 'point of interest'. This icon may change as the hazard changes, for instance by changing colour or size.

Of course other equipment such as mobile phones and portable computers that have positioning capability may be employed instead of a dedicated satellite navigation system. Navigation and mapping functionality is now available in mobile telephones and other Personal Data Assistants (PDA), which feasibly extends beyond vehicles and feasibly permits driver to take the warning device with them from vehicle to vehicle.

Alternatively, or in addition, the radio signal may be able to work co-operatively with motor vehicle controls to reduce vehicle speed when a vehicle is approaching the level crossing.

Brief Description of the Drawing

An example of the invention will now be described with reference to the accompanying drawings, in which:

Fig. 1 is a block diagram of a locomotive warning system.

Fig. 2 is a block diagram of a road vehicle warning system. Best Modes of the Invention

Referring to Fig. 1, a train driver's control cab is equipped with a vigilance system 10, being a state machine that provides programmed responses according to its current logical state, and includes clocks and counters that procure automatic changes of state (from "suppressed "through several "alarm" states to an "emergency braking" state) according to the passage of time and the drivers response to audible and visual alarms. The vigilance system will make use of a number of warning devices, and one or more driver acknowledgement devices in connection with its ordinary operation.

Also there is an electronic map of all the track routes of the rail system, stored in a programmable database 20. In this electronic map 20 each rail line is overlaid along its length with a series of partially overlapping (rectangular) zones. A suitable shape and size for each zone has been found to be a square of forty metres per side. This size and shape has been derived from consideration of the complexity in developing maps and ease of data processing required by on-train equipment, balanced against the requirement for sufficient spatial resolution.

Each zone is identified as belonging to one of a multiplicity of track classes. As a result geographical lengths of the track, which may be made up of one, several or many of the zones, will belong to a particular class.

A simple classification scheme may operate as follows:

All metropolitan tracks over which the train operates are assigned to a first class.

Freight tracks are assigned to a second class.

Country tracks are assigned to a third class.

Any length of track including an obstacle or hazard is assigned to a fourth class; this is the class requiring the highest vigilance.

A further programmable database 30 contains plural sets of vigilance system control functions; one set for each class. A satellite receiver 40 is provided for receiving position information from a geo- positioning satellite system, such as GPS, 45 to enable the position of the train to be determined in real time.

The control unit operates to identify the class of a zone corresponding to the vehicles current position (and zone) according to the following process:

If poor signal coverage inhibits GPS reception, for instance because the vehicle is in a tunnel, steep cutting, dense cityscape or landscape, underneath large bridges or within a workshop, the control unit will determine the fourth class; which has the strictest timings.

If a GPS signal is present and the vehicle is located on an explicitly zoned track, the control unit will determine the class corresponding to the zone.

If a GPS signal is present and the vehicle is not on an explicitly zoned track but the zone can be inferred, the control unit will determine the class of the inferred zone.

If a GPS signal is present and the vehicle is not on an explicitly zoned track and the zone cannot be inferred, the control unit will determine the fourth class.

If a GPS signal is present and the vehicle is in a hazard zone, the control unit will determine the fourth class.

In general, using the location information the Control Unit 50 is programmed to directly identify the class of the zone in which the train is currently located. Having done so, the Control Unit 50 selects the set of vigilance system control functions applicable to the class of the section of track and invokes their use in the vigilance system. Invocation may take place by mere selection when the sets of control functions are stored in the vigilance system, or by downloading the sets into the system.

As a result the vigilance system operates differently in each class of zone. For instance, when the train enters a zone classified as having track conditions that justify higher than normal levels of driver vigilance, the control unit will invoke a set of control functions in the vigilance system that require the driver to respond to more frequent prompts and may require different responses.

In one example, one or more contiguous zones along a stretch of track may be classed as containing a level crossing. The set of vigilance system control functions applicable to a level crossing class are automatically invoked when the train enters this stretch. As we have discussed above the control functions generally include requirements for the driver to acknowledge the vigilance system by taking an action, such as pressing a button or possibly sounding a horn.

In this specific case the control functions will require the driver to demonstrate heightened vigilance. The required degree of vigilance may be dependent on other factors whether or not related to the class of the zone, such as the speed of the train, the degree of curve, quality of visibility, weather conditions, the drivers state of vigilance and many other factors.

The vigilance system control functions for a level crossing zone will also contain programmed decision logic that determines time to arrival of the train to the crossing. And at either a set distance from the level crossing, or a selected time before arrival at the level crossing the control functions will activate relays to flash lights on the front of the train, preferably red lights, or red and blue alternating lights, and also automatically actuate ditch lights (flashing white lights along the side of the locomotive).

The control functions also cause transmission of a coded radio warning signal having a specified range. The radio path may be direct from the train to a motor vehicle, via repeaters, or through a wide area network attached to a computerised central administration function, controlling communication with many trains and many vehicles.

The radio is capable of transmitting signals on one or simultaneously on multiple channels; in which case the signalling protocols and coding are different for different channels. The transmission signal strength of at least one channel is dynamically and configurably adjustable to signal propagation path ranges of between 500 Meters to 2000 Meters from the railroad crossing. The particular range limitation applied in any particular circumstance is selected to prevent the signal being received by a motor vehicle unlikely to be approaching the crossing.

The communications protocol applied to the channel allows the transmitted coded radio warning signal to break into an RF communications channel in the vehicles on-board satellite navigation device. This channel is used (at other times) to relay real-time information concerning, say, traffic congestion, to the satellite navigation system.

Referring now the Fig. 2, inside the road vehicle there is a radio receiver 130 incorporated into the on-board satellite navigation system 100'. Once received, additional functionality 140 in the satellite navigation system may process the trajectory of the vehicle to determine whether the vehicle is going to intersect the crossing, before enabling warnings to the driver. The warnings themselves may be audible via loudspeaker 110 or visual via display 120, or both.

Alternatively, or in addition, the radio signal may be able to work co operatively with motor vehicle controls to reduce vehicle speed when a vehicle is approaching the level crossing.

The radio signal can also be coded to control a warning process, such as flashing lights, at the crossing, or roadside warning signals some distance in advance of the crossing.

Parts of such a train-borne warning system are able to be operated with no additional trackside works or maintenance; for instance where all the equipment is locomotive or train mounted.

Further equipment, such as motor vehicle carried warning devices or level crossing or roadside warnings can be added to the train-borne system electively and progressively. The control unit 50 also provides inputs to one or more event recorders 60, including image records, and may be used to initiate the commencement of a real time record such as CCTV of events at or near the crossing, in front of the train, or in the train driver's cab. The event recorder will log the time and location, provided GPS reception is available, of emergency brake applications

Although the invention has been described with reference to a particular example, it should be appreciated that it could be exemplified in many other forms and in combination with other features not mentioned above. For instance, further logical inputs can be added to the system, such as a measure of driver drowsiness obtained by a suitably objective biometric process, to further condition the control functions.

The control unit may be incorporated into a programmable device such as a field programmable gate array (FPGA) or a complex programmable logic device (CPLD).

Multiple electronic maps may be pre-loaded into the control units. Each map may contain an 'effective date' specifying the date and time on which the map is to become effective. Pre-loading zone maps into a fleet of control units allows simultaneous reconfiguration of the fleet when the effective date is reached.

Secure authentication may be employed to allow only approved maps to be loaded in field. A PDA or laptop is used to upload the map to the control unit.

A multi-line display in the driver's control cab may be used to display the active zone map, the next zone map scheduled to take effect, the firmware version and the current track zone. Emergency brake application logs may be displayed on the screen by pressing a 'select' button.

The control units may be automatically configured at installation for use on different vehicles. This ensures a single control unit can be fitted to different vehicle classes, even if each class requires different vigilance system and interfaces. A universal mounting arrangement also allows fitment of the control units to different vehicle classes while providing easy viewing of the screen. A display associated with the control unit will operate in portrait or landscape mode depending on the mounting arrangement.

The control unit can be configured to notify train control, via activation of an emergency radio, if a driver has not responded to an emergency brake application within a set time (indicating possible incapacitation). This allows train control to contact the driver to establish the extent of the incident and arrange further assistance if required.

The majority of issues arising from signal loss can be overcome with the use of a dead- reckoning system. Dead-reckoning systems infer vehicle position by observing the vehicles acceleration in two dimensions while also considering the distance travelled by the vehicle during times when the GPS signal is unavailable.

In addition, the example above provides warnings to the driver of a motor vehicle via a satellite navigation system. However, many other systems are able to provide these warnings, for instance both mobile phones and PDA's are able to transmit warnings, and they may be equipped with global positioning functionality and mapping tools. Even an ordinary radio is able to be used to relay the warning.

Also, the transmission from the train or crossing has a specified range. This range may be specified in terms of distance, as in the example above, or by some logical distance. For instance, by using a "post-coded" type of addressing, the range may be all receivers in an area defined by some map definition. This could require a complicated communications protocol, with dynamic addressing to a map sector associated with the crossing location. The receiver in the motor vehicle might also dynamically change its address according to its location.

Claims

CLAIMS:

1. A railroad warning system for grade crossings, comprising a radio transmitter located on a train, to selectively transmit real-time radio warning signals while the train is in the vicinity of a crossing; a radio receiver located in a road vehicle, operable to receive radio warning signals, and relay an audible or visual warning related to the current hazard presented by the train, in the event the vehicle is determined to be approaching the crossing.

2. A railroad warning system according to claim 1, wherein the radio transmitter is associated with a satellite positioning system that is able to determine when the train is in the vicinity of the crossing.

3. A railroad warning system according to claim 1 or 2, wherein the radio warning signal contains information about the degree of hazard.

4. A railroad warning system according to claim 1, 2, or 3 wherein the receiver in the motor vehicle is associated with satellite positioning equipment in the vehicle.

5. A railroad warning system according to any preceding claim, wherein the radio transmitter transmits the radio warning signal with a preselected limited signal strength that determines the range over which the transmission can be properly received, and vehicles outside the range will be determined not to be approaching the crossing.

6. A railroad warning system according to any preceding claim, wherein the radio transmitter transmits the radio warning to particular road vehicles using a logical address.

7. A railroad warning system according to any preceding claim, wherein the road vehicle has an on board satellite navigation system, and the radio reception capabilities of this equipment are utilized to receive the radio warning signal.

8. A railroad warning system according to claim 7, wherein the radio warning signal is interpreted by the messaging functionality of the satellite navigation equipment and transmitted from loudspeakers inside the vehicle to warn the driver.

9. A railroad warning system according to claim 8, wherein the satellite navigation system is interrogated to determine whether the vehicle is travelling on a road that interests the crossing, or whether the motor vehicles is travelling towards the crossing, or both; before the determining whether to warn the driver.

10. A railroad warning system according to any preceding claim, wherein the radio warning signal works co-operatively with motor vehicle controls to reduce vehicle speed when a vehicle is approaching the level crossing.