Locomotive/train navigation system and method

• US 7,650,207 B2
• Filed: 05/03/2006
• Issued: 01/19/2010
• Est. Priority Date: 05/04/2005
• Status: Active Grant

• Current Assignee: Australian Rail Track Corp. Ltd. (Government of Australia)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Metzger, Thomas R.
• Primary Examiner(s): Tran; Khoi
• Assistant Examiner(s): SAMPLE, JONATHAN L
• Application Number:
  US11/416,068
• Publication Number:
  US 20060253233A1
• Time in Patent Office: 1,357 Days
• Field of Search: 701/19, 701/1, 701/200, 332/87, 333/38, 335/321, 336/51
• US Class Current: 701/19
• 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: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence

Abstract

In a rail track system having transition points, a locomotive having a navigation system (such as a combined inertial/GPS location system) moves along an initially known track and enters the “halo” surrounding a track transition to begin data collection/logging to accumulate successive position information data points as the locomotive moves into, progresses through, and exits the “halo.” The collected data for movement within the “halo” is then subject to a best fit assessment relative to the data pre-stored in the track database.

Claims

1. A method of determining track identification for a locomotive passing through a transition in a trackway system, the transition having at least two possible exit tracks, comprising the steps:

defining an area about at least one transition in the trackway system for which track identification is desired;

logging position information upon entry by the locomotive in the defined area about the at least one transition until the locomotive exits the defined area, the position information including satellite-based GPS information, wheel tachometer information, and inertial information derived from integrated acceleration values; and

conducting a best fit analysis as a function of at least one of the latitude, longitude, and azimuth between the logged data and a pre-stored database to determine which of the exit tracks is occupied by the locomotive.

2. The method of claim 1, wherein said last-mentioned step includes:

conducting a best fit analysis as a function of at least two of the latitude, longitude, and azimuth between the logged data and a pre-stored database to determine which of the exit tracks is occupied by the locomotive.

3. The method of claim 1, wherein said last-mentioned step includes:

conducting a best fit analysis as a function of the latitude, longitude, and azimuth between the logged data and a pre-stored database to determine which of the exit tracks is occupied by the locomotive.

4. The method of claim 1, wherein said last-mentioned step includes:

conducting a best fit analysis as a function of the difference between the logged at least one of the latitude, longitude, and azimuth and the corresponding value in the pre-stored database.

5. A method of determining track identification for a locomotive passing through a transition in a trackway system, the transition having at least two possible exit tracks, comprising the steps:

defining a perimeter about at least one transition in the trackway system for which track identification is desired;

logging position information upon passage by the locomotive over the defined perimeter about the at least one transition until the locomotive exits the defined perimeter, the position information including satellite-based GPS information, wheel tachometer information, and inertial information derived from integrated acceleration values; and

conducting a best fit analysis as a function of at least one of the latitude, longitude, and azimuth between the logged data and a pre-stored database to determine which of the exit tracks is occupied by the locomotive.

6. The method of claim 5, wherein said last-mentioned step includes:

conducting a best fit analysis as a function of at least two of the latitude, longitude, and azimuth between the logged data and a pre-stored database to determine which of the exit tracks is occupied by the locomotive.

7. The method of claim 5, wherein said last-mentioned step includes:

conducting a best fit analysis as a function of the latitude, longitude, and azimuth between the logged data and a pre-stored database to determine which of the exit tracks is occupied by the locomotive.

8. The method of claim 5, wherein said last-mentioned step includes:

conducting a best fit analysis as a function of the difference between the logged at least one of the latitude, longitude, and azimuth and the corresponding value in the pre-stored database.

9. A method of updating a trackway database having position information therein regarding at least one transition in a trackway system, the at least one transition having a pre-defined perimeter, an entry track, and at least two exit tracks, said method comprising:

logging the position of a locomotive moving through the transition during the time period between the locomotive passing through the perimeter on the entry track and passing through the perimeter on an exit track, the position information including satellite-based GPS information, wheel tachometer information, and inertial information derived from integrated acceleration values;

repeating said first-mentioned step to log a plurality such moving-through-the-transition events;

updating the values stored in the trackway database for that transition as a function of the plurality of logged transition events.

10. The method of claim 9, further comprising, prior to said updating step, the step of subjecting the logged data to a validity test and discarding any data that does not pass the validity test.

11. The method of claim 9, wherein the updating step comprises merging the stored and logged data values.

12. The method of claim 9, wherein the updating step comprises replacing the stored values with the logged data values.