AU2011308097B2 - A railroad track inspection vehicle - Google Patents

Abstract

The present invention relates to a speed control method for an unmanned railway track inspection vehicle. The method includes the step of determining that the vehicle encounters a hazard. The method further includes the step of automatically, without human intervention, reducing the speed of the vehicle responsive to determining that the vehicle encounters the hazard. The speed control method is improved compared with known methods whereby the speed of the vehicle is automatically reduced when encountering the hazard so that the vehicle does not encounter the hazard at an unreasonably high speed. The hazard may be any one of a railway crossing, a trackside worker or trespasser, an unauthorized passenger, a track obstruction, a track gauge infringement, a track defect, a broken or absent rail, or a local hazard.

Description

WO 2012/040794 PCT/AU2011/001261 1 A RAILROAD TRACK INSPECTION VEHICLE TECHNICAL FIELD The present invention generally relates to railroad or railway track inspection vehicles including, for example, track geometry cars and track checkers. BACKGROUND The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge. Railway track inspection vehicles are used to audit the integrity of railway tracks. These vehicles are typically used to test several geometric parameters of the track and structures without obstructing normal railway operations. Some of the parameters generally measured include position, curvature, alignment of the track, smoothness, the cross level of the two rails, features of infrastructure and structure gauge. The vehicles use a variety of sensors, measuring systems, and data management systems to record the measured parameters which are then later used to form a quality index of the inspected track. Some railway track inspection vehicles are unmanned to prevent the possibility of injury in the event of a catastrophic track failure. US 5,627,508 discloses an unmanned Railroad track inspection vehicle which acts as a pilot vehicle traveling before a train. Information gathered by the pilot vehicle's sensor array is transmitted to the train to enable the train's driver to have time to react to hazards. The pilot vehicle is remotely controlled from the train and maintains a safe stopping distance from the train as the train speed varies. The speed of the pilot vehicle is reactionary upon the speed of the train and the decisions of the driver, and can undesirably result in the leading pilot vehicle encountering hazards at unreasonably high speeds.

PCT/AU2011/001261 2 Received 17/07/2012 It is an object of the present invention to provide an unmanned railway track inspection vehicle with improved speed control and/or hazard recognition. Embodiments of the present invention provide a railway track inspection vehicle which operates independently of a train. SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided an unmanned railway track inspection vehicle including a controller for reducing the speed of the vehicle subsequent to determining that the vehicle encounters a hazard. The vehicle may further include an image capture system for capturing at least one image of the hazard. The hazard may be a railway crossing and the controller may be configured to perform image processing on the image to identify flashing signal lights. The hazard may be a trackside worker and the controller may be configured to perform image processing- on the image to identify a vest worn by the worker. The vehicle may further include radar system for detecting a landmark located proximal to the hazard to thereby determine that the vehicle is approaching the hazard. The vehicle may further include a Global Positioning System (GPS) for determining the location of the vehicle. The vehicle may include a storage media storing the known location of the hazard and the controller may determine that the vehicle is approaching the hazard by comparing the location of the vehicle with the location of the hazard. Alternatively, the vehicle may further include a transceiver for sending the location of the vehicle to a central command center and the controller may determine that the vehicle is approaching the hazard when the transceiver receives a hazard alert message from the central command center or operator AMENDED SHEET PCT/AU2011/001261 3 Received 17/07/2012 station. In one embodiment, the railway track inspection vehicle may operate independently of a train. The vehicle may include a passenger detector for detecting a passenger riding on the vehicle. The passenger detector may include scales for sensing the weight of the passenger boarding the vehicle and the vehicle may be stopped upon sensing the presence of the passenger. The vehicle may include an emergency stop arrangement and the vehicle may be stopped upon triggering the emergency stop arrangement when the vehicle comes into contact with an object. The emergency stop arrangement may include emergency stop buttons located around the periphery of the vehicle. The vehicle may include a gyroscope, accelerometer and altimeter for measuring vehicle pitch, roll and yaw readings, vehicle acceleration and braking, and vehicle altitude and the vehicle may be stopped responsive to determining that the vehicle has come into contact with the hazard in accordance with a sudden change in the readings. The vehicle may include a marker sensor for sensing a marker positioned on or near the track proximal to the hazard, the speed of the vehicle being automatically reduced or the vehicle may be stopped responsive to sensing the marker. The marker may be a magnet. The vehicle may also include a rail proximity sensor for sensing the proximity of rails along which the vehicle travels. The speed of the vehicle may be automatically reduced or the vehicle may be stopped responsive to sensing that the proximity of a rail exceeds a predetermined threshold in the event of a derailment of the vehicle. According to another aspect of the present invention, there is provided a speed control system for an unmanned railway track inspection vehicle as described above, the control system configured to reduce the speed of the vehicle subsequent to determining that the vehicle encounters a hazard. AMENDED SHEET PCT/AU2011/001261 Received 17/07/2012 According to a further aspect of the present invention, there is provided a speed control method for an unmanned railway track inspection vehicle as described above, the method including the steps of: determining that the vehicle encounters a hazard; and automatically, without human intervention, reducing the speed of the vehicle responsive to determining that the vehicle encounters the hazard. The speed control method is improved compared with known methods whereby the speed of the vehicle is automatically reduced when encountering the hazard so that the vehicle does not encounter the hazard at an unreasonably high speed. The hazard may relate to a poor track condition. In one embodiment, the method includes the step of communicating the hazard or track condition through alarm, warnings or media. The encountering may involve approaching-or coming into contact with the hazard. The hazard may be any one of a railway crossing, a trackside worker or trespasser, an unauthorized passenger, a track obstruction, a track gauge infringement, a track defect, a broken or absent rail, or a local hazard. The hazard may be a railway crossing. In one embodiment, the step of determining involves detecting a characteristic of the railway crossing. The characteristic may be flashing signal lights which are visually detected by performing image processing. Alternatively, the characteristic may be a landmark. In another embodiment, the characteristic may be a landmark detected using ultrasonic radar. Alternatively, the step of determining may involve comparing the location of the vehicle with the known location of the railway crossing. The location of the vehicle can be determined using Global Positioning System (GPS) or predetermined linear distance measurements (e.g. odometer) for positioning. AMENDED SHEET PCT/AU2011/001261 Received 17/07/2012 The hazard may be one or more trackside workers or trespassers. The step of determining may involve sensing vests worn by respective workers or laser reflection detecting proximity to a trespasser. The step of automatically reducing the speed may involve stopping the vehicle upon detecting that the separation between the workers and the vehicle is less than a safe distance. The method may further involve the step of sending an alarm responsive to determining that the vehicle encounters the hazard. The hazard may be an unauthorized passenger riding on the vehicle. The step of determining may involve sensing the weight of the passenger boarding the vehicle. The step of automatically reducing the speed may involve stopping the vehicle upon sensing the presence of the passenger. The presence of the passenger may be determined using either weight or proximity sensors. The hazard may be a track gauge infringement. The step of determining may involve a laser sweep of a track corridor. The step of automatically reducing the speed may involve stopping the vehicle upon sensing an obstruction that will cause damage to the vehicle and cannot be passed..

The hazard may be a local hazard not within the track gauge. The step of determining may involve video and photo analysis to determine hazards including any one of water buildup, landslides, debris and other irregular objects. The step of automatically reducing the speed may involve bringing the vehicle to a stop at a predetermined or landmark position, recording stopping data and sending information relating to the stop. The hazard may be a track obstruction. The step of determining may involve the vehicle colliding with the track obstruction. The hazard may be a broken rail of the track along which the vehicle travels. AMENDED SHEET WO 2012/040794 PCT/AU2011/001261 6 BRIEF DESCRIPTION OF THE DRAWINGS Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows: Figure 1 is a schematic diagram of a control system for controlling an unmanned railway track inspection vehicle in accordance with an embodiment of the present invention; Figure 2 is a block diagram of the unmanned railway track inspection vehicle shown in Figure 1; Figure 3 is a flowchart of a speed control method for the unmanned railway track inspection vehicle shown in Figures 1 and 2; and Figure 4 is a flowchart of a speed control routine of the speed control method of Figure 3, the routine being performed for each identifiable hazard. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS According to an embodiment of the present invention, there is provided a control system 100 shown in Figure 1 for controlling an unmanned railway track inspection vehicle 102. The control system 100 includes a central command centre 104 which is in two-way communication with the vehicle 102 via a communications network 106. The communications network 106 includes both a radio frequency (RF) radio network, as well as a mobile telephone network which can be instead be used in the event that the RF network becomes unavailable or the vehicle 102 is out of range. The lightweight inspection vehicle 102 is a drone that can be remotely controlled by the central command centre 104, and independently of a train.

WO 2012/040794 PCT/AU2011/001261 7 Turning to Figure 2, the unmanned railway track inspection vehicle 102 includes a controller 200 for determining that the vehicle encounters a hazard. The controller 200 is configured to automatically (i.e. without human intervention) reduce the speed of the vehicle 102 responsive to determining that the vehicle 102 encounters the hazard. Advantageously, the speed of the vehicle 102 is automatically reduced when encountering the hazard so that the vehicle does not encounter the hazard at an unreasonably high speed. A detailed description of the inspection vehicle 102 is provided below. The controller 200 contains a software product 202 in resident memory. In turn, the software product 202 contains computer readable instructions for execution by a processor 204 of the controller 200 to perform the speed control method outlined below. The processor 204 is interfaced to a storage device (e.g. hard disc) containing a hazard database 206 of known hazard locations. The vehicle 102 further includes a Global Positioning System (GPS) 208 for determining the location of the vehicle 2. The controller 200 can determine that the vehicle 102 is approaching a hazard by comparing the determined location of the vehicle 102 with the location of the hazard stored in the hazard database 206. The onboard database also stores event information and other data relating to the operation of the vehicle 102. The vehicle 102 further includes a transceiver 210, in turn, including both an RF and a mobile phone (Next Generation) modem for communicating with the central command centre 104 via the communications network 106. The transceiver 210 also provides two-way audio communication to workers on the track. The vehicle 102 further includes an image capture system 212 for capturing at least one image of the hazard. As can best be seen in Figure 1, the image capture system 212 includes an upper camera 108 mounted on a telescopic pole 110 to capture images of the track an its surrounds, and a pair of lower cameras 112 mounted to capture images of respective rails of the track along which the vehicle 102 travels. The hazard can be a railway crossing and the WO 2012/040794 PCT/AU2011/001261 8 controller 200 is configured to perform image processing of the captured images to identify flashing signal lights at the crossing. The image processing involves identifying a flashing frequency and/or color of the signal lights. The image capture system 212 further includes pan-tilt-zoom control so that an operator can manually control camera positioning and zoom. Alternatively, the hazard can be a trackside worker and the controller 200 is configured to perform image processing of the captured images to identify a vest worn by the worker. The image processing involves identifying a distinctive pattern and/or color of the vest. The vehicle 102 further includes an ultrasonic radar system 214 for detecting a landmark located proximal to the hazard to thereby determine that the vehicle is approaching the hazard. The vehicle 102 also includes a passenger detector 216 for detecting a passenger riding on the vehicle 102. The passenger detector 216 includes electronic scales for sensing the weight of the passenger boarding the vehicle 102, and the vehicle 102 is immediately stopped by the controller 200 upon sensing the presence of the passenger. In this manner, unauthorised persons jumping onto the vehicle 102 cannot ride on the vehicle 102 which can be extremely dangerous. The vehicle 102 further include a emergency stop button arrangement 218 and the controller 200 immediately stops the vehicle 102 upon triggering the emergency stop button arrangement when the vehicle collides and comes into contact with a track obstruction. The emergency stop button arrangement 218 includes emergency stop buttons located around the periphery of the vehicle 102. The vehicle 102 further includes a gyroscope 220 for measuring vehicle pitch, roll and yaw readings. The vehicle 102 further includes an accelerometer and altimeter for respectively measuring vehicle acceleration and braking, and vehicle altitude. The vehicle 102 is stopped by the controller 200 responsive to WO 2012/040794 PCT/AU2011/001261 9 determining that the vehicle has come into contact with the hazard (e.g. a fallen tree across the tracks) in accordance with a sudden change in the readings. Furthermore, the vehicle includes a marker sensor 222 for sensing a marker positioned on or near the track proximal to the hazard. The speed of the vehicle 102 is automatically reduced or the vehicle 102 is stopped by the controller 200 responsive to sensing the marker. The marker is typically a magnet located near the tracks. The vehicle 102 also includes a rail proximity sensor 224 for sensing the proximity of rails along which the vehicle 102 travels. The speed of the vehicle 102 is automatically reduced or the vehicle 102 is stopped by the controller 200 responsive to sensing that the proximity of a rail exceeds a predetermined threshold in the event of a derailment of the vehicle 2. The vehicle 102 also includes a motor assembly or transmission 226 which is driven by the controller 200 to control the speed of the vehicle 102. The vehicle 102 also includes a pendant control system 228 which enables local wireless control of the vehicle 102 for depot and safety control. A speed control method 300 for the unmanned railway track inspection vehicle 102 is shown in Figure 3. At step 302, the controller 200 receives an activation message sent from the central command centre 104. The activation message includes the location of the destination to which the vehicle 102 is required to travel. At step 304, the controller 200 sets the vehicle speed to the desired travel speed (which typically varies between 30 and 45km/hour) and thereby drives the motor assembly 226 accordingly.

WO 2012/040794 PCT/AU2011/001261 10 At step 306, the controller 200 performs a speed control routine 400 shown in Figure 4 for each identifiable hazard. Speed control routine 400 is later described in detail below. The identifiable hazards relate to a railway crossing, a trackside worker, an unauthorized passenger, a track obstruction and an absent or broken rail. At query step 308, the controller 200 queries whether the destination location has been reached using GPS 208. If the destination has been reached, the controller 200 sets the vehicle speed to zero at step 310 and thereby applies vehicle brakes and stops driving the motor assembly 226. If the destination has not been reached, the controller 200 continues to drive the motor assembly 226 and the method 300 returns to step 306 where a speed control routine 400 for each hazard is once again performed. The speed control routine 400 performed for each identifiable hazard is shown in Figure 4. At query step 402, the controller 200 queries whether the vehicle 102 encounters a hazard. The encountering can involve approaching or coming into contact with the hazard. At step 404 if the controller 200 determines that the vehicle 102 encounters a hazard, the controller 200 automatically sets the vehicle speed to the reduced hazard speed (which is typically 20km/hour) and thereby drives the motor assembly 226 and vehicle brakes accordingly. If the hazard speed was already set, the vehicle merely maintains the hazard speed as the hazard is still being encountered. At step 406 if the controller 200 determines that the vehicle 102 does not encounter a hazard, the controller 200 automatically sets the vehicle speed to the desired travel speed and thereby either maintains the desired travel speed or increases the travel speed from the hazard speed as the hazard is no WO 2012/040794 PCT/AU2011/001261 11 longer encountered. The controller 200 drives the motor assembly 226 accordingly. At step 408, the controller 200 send a alarm message to the command centre 104 indicating the hazard was encountered. One of the hazards which the controller 200 can identify is the presence of a railway crossing. The image capture system 212 can be used to detect a distinctive characteristic of the railway crossing. The distinctive characteristic can be flashing signal lights which are visually detected by performing image processing. Alternatively, the distinctive characteristic can be a landmark (e.g. crossing gate-operators tower) located in close proximity to the crossing. In addition, the radar system 214 can detect the landmark. Alternatively, the controller 200 can determine that the vehicle 102 approaches and encounters the railway crossing, by comparing the location of the vehicle 102 determined using GPS 208 with the known location of the railway crossing stored in the hazard database 206. The controller 200 automatically reduces the speed of the vehicle 102 from the travel speed to the railway crossing hazard speed, responsive to determining that the vehicle 102 encounters the railway crossing. Another of the hazards which the controller 200 can identify is the presence of one or more trackside workers. The controller 200 can determine that the vehicle 102 approaches and encounters the trackside workers using the image capture system 212. The controller 200 can perform image processing to sense vests worn by the workers and can automatically stop the vehicle 102 (i.e. zero hazard speed) responsive to encountering the workers when the separation between the workers and the vehicle 102 is less than a safe distance. Another of the hazards which the controller 200 can identify is the presence of an unauthorized passenger riding on the vehicle. The controller 200 can WO 2012/040794 PCT/AU2011/001261 12 determine that the vehicle 102 encounters the passenger jumping on the moving vehicle 200 using the passenger detector 216. The passenger detector 216 senses the weight of the encountered passenger boarding the vehicle 102 and the controller 200 then automatically stops the vehicle 102. Another of the hazards which the controller 200 can identify is the presence of a track obstruction. The controller 200 can determine that the vehicle 102 collides with and encounters the track obstruction using the emergency stop button arrangement 218 or the gyroscope 220. The controller 200 can automatically stop the vehicle 102 responsive to determining that the vehicle 102 encounters the track obstruction. Alternatively, the controller 200 can determine that the vehicle 102 encounters the track obstruction using the marker sensor 222 which senses a magnetic marker positioned by a worker near the track and proximal to the track obstruction. The controller 200 can automatically stop or reduce the speed of the vehicle 102 responsive to determining that the vehicle 102 encounters the hazard indicated by the marker. Another of the hazards which the controller 200 can identify is the absence of a rail of the track along which the vehicle 102 travels. The controller 200 can determine that the vehicle 102 encounters the hazard using the rail proximity sensor 224. The controller 200 automatically reduces the speed of the vehicle 102 responsive to sensing that the proximity of a rail exceeds a predetermined threshold indicating a derailment of the vehicle 102. A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present invention. For example, in the preferred embodiment, the controller 200 can determine that the vehicle 102 approaches and encounters the railway crossing using an onboard hazard database 206. In an alternative embodiment, the central command centre 104 may instead receive the vehicle location from GPS 208 WO 2012/040794 PCT/AU2011/001261 13 via communications network 106 and store the hazard database 206. Accordingly, the central command centre 104 (in place of the controller 200) can determine that the vehicle 102 is approaching the railway crossing by comparing the received vehicle location with the location of the hazard stored in the local hazard database 206. The controller 200 determines that the vehicle 102 encounters the railway crossing when the transceiver 210 receives an associated hazard alert message sent from the central command centre 104. In one embodiment, the hazard may be a trespasser and the vehicle 102 can perform laser reflection to detect the trespasser. In another embodiment, the hazard may relate to a track gauge infringement. Determining the hazard can involve laser sweeping a track corridor. In one embodiment, the step of automatically reducing the vehicle speed can involve stopping the vehicle upon sensing an obstruction that will cause damage to the vehicle and cannot be passed. In one embodiment, the hazard can be a local hazard not within the track gauge. The step of determining the hazard involves video and photo analysis to determine hazards including any one of water buildup, landslides, debris and other irregular objects. The step of automatically reducing the vehicle speed can involve bringing the vehicle to a stop at a predetermined or landmark position, recording stopping data and sending information relating to the stop to the command centre. In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.

Claims (21)

1. An unmanned railway track inspection vehicle including a controller for reducing the speed of the vehicle subsequent to determining that the vehicle encounters a hazard.

2. A vehicle as claimed in claim 1, further including an image capture system for capturing at least one image of the hazard.

3. A vehicle as claimed in claim 2, wherein the hazard is a railway crossing and the controller is configured to perform image processing on the image to identify flashing signal lights.

4. A vehicle as claimed in claim 2, wherein the hazard is a trackside worker and the controller is configured to perform image processing on the image to identify a vest worn by the worker.

5. A vehicle as claimed in claim 1, further including a radar -system for detecting a landmark located proximal to the hazard to thereby determine that the vehicle is approaching the hazard.

6. A vehicle as claimed in claim 1, further including a Global Positioning System (GPS) for determining the location of the vehicle, the vehicle including a storage media storing the known location of the hazard and the controller determining that the vehicle is approaching the hazard by comparing the location of the vehicle with the location of the hazard.

7. A vehicle as claimed in claim 1, further including a transceiver for sending the location of the vehicle to a central command center wherein the controller determines that the vehicle is approaching the hazard when the transceiver receives a hazard alert message from the central command center or operator station. AMENDED SHEET PCT/AU2011/001261 15 Received 17/07/2012

8. A vehicle as claimed in claim 1, further including a passenger detector for detecting a passenger riding on the vehicle, the passenger detector including scales for sensing the weight of the passenger boarding the vehicle.

9. A vehicle as claimed in claim 1, further including an emergency stop arrangement wherein the vehicle is stopped upon triggering the emergency stop arrangement when the vehicle comes into contact with an object.

10. A vehicle as claimed in claim 1, further including a marker sensor for sensing a marker positioned on or near the track proximal to the hazard, the speed of the vehicle being automatically reduced or the vehicle stopped responsive to sensing the marker.

11. A vehicle as claimed in claim 1, further including a rail proximity sensor for sensing the proximity of rails along which the vehicle travels, the speed of the vehicle being automatically reduced or the vehicle being stopped responsive to sensing that the proximity of a rail exceeds a predetermined threshold in the event of a derailment of the vehicle.

12. A speed control system for the unmanned railway track inspection vehicle as claimed in claim 1, the control system configured to reduce the speed of the vehicle subsequent to determining that the vehicle encounters a hazard.

13. A speed control method for the unmanned railway track inspection vehicle as claimed in claim 1, the method including the steps of: determining that the vehicle encounters a hazard; and automatically, without human intervention, reducing the speed of the vehicle responsive to determining that the vehicle encounters the hazard.

14. A method as claimed in claim 13, wherein the hazard relates to a poor track condition. AMENDED SHEET PCT/AU2011/001261 16 Received 17/07/2012

15. A method as claimed in claim 13, wherein said encounter involves approaching or coming into contact with the hazard.

16. A method as claimed in claim 13, wherein the step of determining involves detecting a characteristic of a railway crossing, the characteristic being one of flashing signal lights which are visually detected by performing image processing, a landmark detected using ultrasonic radar or a location of the railway crossing.

17. A method as claimed in claim 13, wherein the hazard is one or more trackside workers or trespassers.

18. A method as claimed in claim 13, wherein the hazard is an unauthorized passenger riding on the vehicle.

19. A method as claimed in claim 13, wherein the hazard is a track gauge infringement or obstruction.

20. A method as claimed in claim 13, wherein the hazard is a local hazard not within the track gauge of the track along which the vehicle travels.

21. A method as claimed in claim 13, wherein the hazard is a broken rail of the track along which the vehicle travels. AMENDED SHEET