Method and system for compensating for wheel wear on a train

• US 7,283,897 B2
• Filed: 07/01/2003
• Issued: 10/16/2007
• Est. Priority Date: 05/31/2002
• Status: Expired due to Term

• 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, CUONG H
• Application Number:
  US10/609,377
• Publication Number:
  US 20040006411A1
• Time in Patent Office: 1,568 Days
• Field of Search: 701/200, 701/213, 701 19- 20, 701/201, 701/207, 701/70, 246/122.R, 731/46, 702/85, 324/166, 104/96, 104/118, 105154-155
• US Class Current: 701/19
• CPC Class Codes: B61K 9/12 Measuring or surveying wheel-rims measuring techniques G01
• 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
• CPC Class Codes: G01C 22/02 by conversion into electric waveforms and subsequent integration, e.g. using tachometer generator G01C22/002, G01C22/004, G01C22/006 take precedence

Abstract

A method and system for compensating for wheel wear uses position and/or speed information from an independent positioning system to measure some distance over which the train has traveled. Wheel rotation information is also collected over the distance. The wheel rotation information and distance and/or speed information are then used to determine the size of the train wheels. The method is performed periodically to correct for changes in wheel size over time due to wear so that the wheel rotation information can be used to determine train position and speed in the event of a positioning system failure.

Claims

1. A method for determining a size of a wheel on a train comprising the steps of:

determining a linear distance traveled by a train during a period of time by calculating a difference in positions reported by a positioning system located on the train at a start of the period and an end of the period;

repeating the determining step a plurality of times;

adding the linear distance from each of the determining steps to form a total distance; and

calculating the wheel size based on the total distance and a total number of wheel revolutions occurring during each of the determining steps.

2. The method of claim 1, wherein the determining steps are performed successively with no separation between each period.

3. The method of claim 1, wherein the determining steps are performed with a separation between at least two successive periods for which a difference is calculated in the determining step.

4. The method of claim 1, wherein the positioning system is a global positioning system.

5. The method of claim 1, in which no portion of the total distance corresponds to a section of track having a grade exceeding a grade threshold.

6. The method of claim 5, further comprising the step of obtaining the grade from a track database using a position from the positioning system as an index.

7. The method of claim 1, wherein the period is one second.

8. A system for determining a size of a train wheel comprising:

a control unit;

a positioning system in communication with the control unit, the positioning system being configured to provide the control unit with positioning information pertaining to the train; and

a revolution counter connected to the control unit, the revolution counter being configured to measure rotation of a train wheel;

wherein the control unit is configured to perform the steps of;

determining a linear distance traveled by a train during a period of time by calculating a difference in positions reported by-the positioning system at a start of the period and at the end of the period;

repeating the determining step a plurality of times;

adding the linear distance from each of the determining steps to form a total distance; and

calculating the wheel size based on the total distance and a total number of wheel revolutions occurring during each of the determining steps.

9. The system of claim 8, wherein the determining steps are performed successively with no separation between each period.

10. The system of claim 8, wherein the determining steps are performed with a separation between at least two successive periods for which a difference is calculated in the determining step.

11. The system of claim 8, wherein the positioning system is a global positioning system.

12. The system of claim 8, wherein no portion of the total distance corresponds to a section of track having a grade exceeding a grade threshold.

13. The system of claim 8, further comprising the step of obtaining the grade from a track database using a position from the positioning system as an index.

14. The system of claim 8, the period is one second.