Method and system for detecting when an end of train has passed a point

• US 6,915,191 B2
• Filed: 05/19/2003
• Issued: 07/05/2005
• Est. Priority Date: 05/19/2003
• Status: Active Grant

• Current Assignee: Siemens Mobility, Inc. (Siemens AG)
• Original Assignee: Quantum Engineering, Inc. (Siemens AG)
• Inventors: Shockley, James Francis, Kane, Mark Edward, Hickenlooper, Harrison Thomas
• Primary Examiner(s): NGUYEN, TAN QUANG
• Application Number:
  US10/440,129
• Publication Number:
  US 20040236482A1
• Time in Patent Office: 778 Days
• Field of Search: 701/19, 701/20, 701/200, 701/117, 701/213, 701/207, 701/215, 246/167.R, 246/182.R, 246/122.R, 246/62, 246/124, 340/903, 340/988, 342/357.07
• US Class Current: 701/19
• CPC Class Codes: B61L 15/0054 Train integrity supervision, e.g. end-of-train [EOT] devices
• CPC Class Codes: B61L 15/0072 On-board train data handling
• CPC Class Codes: B61L 2205/04 Satellite based navigation systems, e.g. global positioning system [GPS]
• CPC Class Codes: B61L 25/021 Measuring and recording of train speed
• CPC Class Codes: B61L 25/025 Absolute localisation, e.g. providing geodetic coordinates
• CPC Class Codes: B61L 25/026 Relative localisation, e.g. using odometer

Abstract

A controller determines that an end of train (EOT) has passed a point through the use of positioning systems at the head of the train (HOT) and the EOT. In a first method, the controller obtains the HOT position at a point of interest from the HOT positioning system. The controller then determines when the train has traveled a distance equal to the length of the train and then interrogates the EOT positioning system. If the difference between this position and the position reported by the HOT positioning system at the point of interest exceeds a threshold, then the EOT has passed the point. In a second method, when the HOT positioning system reaches a point of interest, the position reported by the EOT positioning system is integrated until the total distance traveled by the EOT equals the length of the train.

Claims

1. A method for determining that an end of train has passed a point comprising the steps of:

determining that a head of a train has reached a first position at a point of interest;

detecting, after the determining step, that the head of the train has traveled a distance past the first position, the distance being at least as long as a length of the train;

obtaining a second position of an end of the train after the detecting step; and

comparing the first position to the second position to verify that the end of the train has passed the point of interest.

2. The method of claim 1, wherein the comparing step is performed by calculating a difference between the first position and the second position and comparing the difference to a threshold.

3. The method of claim 2, wherein the threshold is zero.

4. The method of claim 2, wherein the threshold includes a safety factor.

5. The method of claim 1, wherein the step of determining that the head of train has traveled the distance is performed by integrating successive differences in position of the head of the train.

6. The method of claim 5, wherein the integrating step is performed at a periodic rate.

7. The method of claim 6, wherein the periodic rate is approximately once every second.

8. The method of claim 1, wherein the step of determining that the head of train has traveled the distance is performed by determining a third position of the head of the train at a time after the head of the train is at the first position and calculating a difference between the third position and the first position.

9. The method of claim 1, further comprising the step of accepting a length of the train from a dispatcher.

10. The method of claim 1, further comprising the step of accepting a length of the train from an operator.

11. The method of claim 1, further comprising the step of determining a length of the train based at least in part on a position reported by a positioning system located at an end of the train and a position reported by a positioning system located at a head of the train.

12. The method of claim 1, wherein the first position is obtained from a first positioning system located at the head of the train and the second position is obtained from a second positioning system located at an end of the train.

13. The method of claim 11, wherein the positioning system located at the end of the train is a Global Positioning System (GPS) receiver and the positioning system located at the head of the train is a GPS receiver.

14. The method of claim 12, further comprising the step of comparing a speed reported by the first positioning system to a speed reported by the second positioning system to detect a separation of the head of the train from the end of the train.

15. A method for determining that an end of train has passed a point comprising the steps of:

determining that a head of a train has reached a first position at a point of interest;

detecting, after the determining step, that an end of the train has traveled a distance at least as long as a length of the train;

obtaining a second position of the end of the train after the detecting step; and

comparing the first position to the second position to verify that the end of the train has passed the point of interest.

16. The method of claim 15, wherein the comparing step is performed by calculating a difference between the first position and the second position and comparing the difference to a threshold.

17. The method of claim 16, wherein the threshold is zero.

18. The method of claim 16, wherein the threshold includes a safety factor.

19. The method of claim 15, wherein the detecting step is performed by integrating successive differences in position of the end of the train.

20. The method of claim 19, wherein the integrating step is performed at a periodic rate.

21. The method of claim 20, wherein the periodic rate is approximately once every second.

22. The method of claim 15, further comprising the step of accepting the length of the train from a dispatcher.

23. The method of claim 15, further comprising the step of determining the length of a train based at least in part on a position reported by a positioning system located at an end of the train and a position reported by a positioning system located at a head of the train.

24. The method of claim 15, wherein the first position is obtained from a first positioning system located at the head of the train and the second position is obtained from a second positioning system located at an end of the train.

25. The method of claim 24, further comprising the step of comparing a speed reported by the first positioning system to a speed reported by the second positioning system to detect a separation of the head of the train from the end of the train.

26. A system for determining that an end of train has passed a point, the system comprising:

a control unit;

a first positioning system in communication with the control unit, the first positioning system being located at a head of a train;

a second positioning system in communication with the control unit, the second positioning system being located at an end of the train;

the control unit being configured to perform the steps of

determining when a head of a train has reached a first position at a point of interest using information from the first positioning system;

detecting when the head of the train has traveled a distance past the first position, the distance being at least as long as a length of the train;

obtaining a second position of an end of the train from the second positioning system when the head of train has traveled the distance; and

comparing the first position to the second position to verify that the end of the train has passed the point of interest.

27. The system of claim 26, wherein the comparing step is performed by calculating a difference between the first position and the second position and comparing the difference to a threshold.

28. The system of claim 27, wherein the threshold is zero.

29. The system of claim 27, wherein the threshold includes a safety factor.

30. The system of claim 26, wherein the step of determining that the head of train has traveled the distance is performed by integrating successive differences in position of the head of the train.

31. The system of claim 30, wherein the integrating step is performed at a periodic rate.

32. The system of claim 31, wherein the periodic rate is approximately once every second.

33. The system of claim 26, wherein the step of determining that the head of train has traveled the distance is performed by determining a third position of the head of the train at a time after the head of the train is at the first position and calculating a difference between the third position and the first position.

34. The system of claim 26, further comprising the step of accepting the length of the train from a dispatcher.

35. The system of claim 26, further comprising the step of determining a length of a train based at least in part on a position reported by the first positioning system and a position reported by the second positioning system.

36. The system of claim 26, wherein the first and second positioning systems are GPS receivers.

37. The system of claim 26, wherein the control unit is further configured to perform the step of comparing a speed reported by the first positioning system to a speed reported by the second positioning system to detect a separation of the head of the train from the end of the train.

38. The system of claim 26, further comprising a storage device connected to the control unit, the control unit further being configured to obtain the point of interest from the track database.

39. A system for determining that an end of train has passed a point, the system comprising:

a control unit;

a first positioning system in communication with the control unit, the first positioning system being located at a head of a train;

a second positioning system in communication with the control unit, the second positioning system being located at an end of the train;

the control unit being configured to perform the steps of

determining a first position of a head of a train at a point of interest;

detecting, after the determining step, when an end of the train has traveled a distance at least as long as a length of the train;

obtaining a second position of the end of the train after the detecting step; and

comparing the first position to the second position to verify that the end of the train has passed the point of interest.

40. The system of claim 39, wherein the comparing step is performed by calculating a difference between the first position and the second position and comparing the difference to a threshold.

41. The system of claim 40, wherein the threshold is zero.

42. The system of claim 40, wherein the threshold includes a safety factor.

43. The system of claim 39, wherein the detecting step is performed by integrating successive differences in position of the end of the train.

44. The system of claim 43, wherein the integrating step is performed at a periodic rate.

45. The system of claim 44, wherein the periodic rate is approximately once every second.

46. The system of claim 39, wherein the control unit is further configured to perform the step of accepting the length of a train from a dispatcher.

47. The system of claim 39, wherein the control unit is further configured to perform the step of determining the length of the train based at least in part on a position reported by the first positioning system and a position reported by the second positioning system.

48. The system of claim 39, further comprising the step of comparing a speed reported by the first positioning system to a speed reported by the second positioning system to detect a separation of the head of the train from the end of the train.

49. The system of claim 39, further comprising a storage device connected to the control unit, the control unit further being configured to obtain the point of interest from the track database.