Method of determining a position of a vehicle on a guideway

• US 9,499,184 B2
• Filed: 12/30/2015
• Issued: 11/22/2016
• Est. Priority Date: 05/03/2013
• Status: Active Grant

• Current Assignee: Ground Transportation Systems Canada Incorporated
• Original Assignee: Thales Canada Incorporated (Thales SA)
• Inventors: Schwellnus, Carl, Bantin, Colin
• Primary Examiner(s): Smith, Jason C
• Application Number:
  US14/984,147
• Publication Number:
  US 20160107662A1
• Time in Patent Office: 328 Days
• US Class Current: 1/1
• CPC Class Codes: B61L 25/02 Indicating or recording positions or identities of vehicles or trains
• CPC Class Codes: B61L 25/023 Determination of driving direction of vehicle or train
• 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: B61L 25/04 Indicating or recording train identities
• CPC Class Codes: B61L 3/121 using magnetic induction

Abstract

A method of determining a position of a vehicle on a guideway includes detecting a position of the vehicle relative to a first reflective positioning element along the guideway. The method also includes detecting a unique identification code of a transponder along the guideway, wherein the transponder is located a first known distance along the guideway from the first reflective positioning element. The method further includes determining the position of the vehicle, using a position determining system, based on a modulated reflection signal received from the transponder, a first non-modulated reflection signal received from the first reflective positioning element, and the first known distance.

Claims

1. A method of determining a position of a vehicle on a guideway, the method comprising:

receiving a first non-modulated reflection signal by a first antenna on-board the vehicle, the first non-modulated reflection signal being associated with a first reflective positioning element along the guideway;

receiving the first non-modulated reflection signal by a second antenna on-board the vehicle;

determining a difference between the first non-modulated signal received by the first antenna and the first non-modulated signal received by the second antenna;

detecting a position of the vehicle relative to the first reflective positioning element along the guideway based on the difference between the first non-modulated signal received by the first antenna and the first non-modulated signal received by the second antenna;

detecting a unique identification code of a transponder along the guideway, wherein the transponder is located a first known distance along the guideway from the first reflective positioning element; and

determining the position of the vehicle on the guideway, using a position determining system, based on a modulated reflection signal received from the transponder, the position of the vehicle relative to the first reflective positioning element, and the first known distance.

2. The method of claim 1, further comprising:

transmitting the determined position of the vehicle on the guideway to an external control system.

3. The method of claim 1, further comprising:

detecting a position of the vehicle relative to a second reflective positioning element along the guideway, the transponder located a second known distance along the guideway from the second reflective positioning element; and

determining a heading of the vehicle based on the modulated reflection signal, a second non-modulated reflection signal received from the second reflective positioning element, the first known distance and the second known distance.

4. The method of claim 1, wherein detecting the position of the vehicle relative to the first reflective positioning element comprises detecting the position of the vehicle relative to a half-wavelength reflector.

5. The method of claim 1, further comprising:

receiving update information from an external control system; and

updating a transponder identification database of the position determining system using the update information.

6. A method of determining a position of a vehicle on a guideway, the method comprising:

emitting an interrogation signal from a position determining system on-board the vehicle;

receiving a modulated reflection signal having a unique identification code by the position determining system, the modulated reflection signal being received from a transponder configured to receive the interrogation signal and emit the modulated reflection signal in response to the interrogation signal;

receiving a first non-modulated reflection signal by the position determining system from a first reflective positioning element configured to receive the interrogation signal and to reflect the interrogation signal to form the first non-modulated reflection signal, the first non-modulated reflection signal being received by a first antenna on-board the vehicle, and by a second antenna on-board the vehicle;

detecting a position of the vehicle relative to the first reflective positioning element along the guideway based on a phase difference between the first non-modulated signal received by the first antenna and the first non-modulated signal received by the second antenna; and

processing the modulated reflection signal and the position of the vehicle relative to the first reflective to determine the position of the vehicle on the guideway.

7. The method of claim 6, wherein the first reflective positioning element is located a first known distance along the guideway from the transponder, and the method further comprises:

processing the position relative to the first reflective positioning element and the first known distance along the guideway from the transponder to determine the position of the vehicle on the guideway.

8. The method of claim 7, further comprising:

communicating the determined position of the vehicle on the guideway to an external control system.

9. The method of claim 6, further comprising:

detecting a position of the vehicle relative to a second reflective positioning element along the guideway; and

processing the modulated reflection signal, the position of the vehicle on the guideway relative to the first reflective positioning element, and a second non-modulated reflection signal received from the second reflective positioning element to determine a heading of the vehicle along the guideway.

10. The method of claim 9, wherein the first reflective positioning element is located a first known distance along the guideway from the transponder, the second reflective positioning element is located a second known distance along the guideway from the transponder, and the method further comprises:

processing the first known distance and the second known distance to determine the heading of the vehicle along the guideway.

11. The method of claim 10, wherein the first known distance is different from the second known distance.

12. The method of claim 6, further comprising:

receiving update information from an external control system; and

updating a transponder identification database of the position determining system using the update information.

13. A method of determining a position of a vehicle on a guideway, the method comprising:

detecting a position of the vehicle relative to a first reflective positioning element along the guideway;

detecting a closest transponder of a plurality of transponders along the guideway, wherein the closest transponder is located a first known distance along the guideway from the first reflective positioning element; and

determining the position of the vehicle, using a position determining system, based on a modulated reflection signal received from the closest transponder, a first non-modulated reflection signal received from the first reflective positioning element, and the first known distance,

wherein detecting the position of the vehicle relative to the first reflective positioning element comprises;

receiving the first non-modulated reflection signal by a first antenna on-board the vehicle and by a second antenna on-board the vehicle;

splitting each of the first non-modulated reflection signal received by the first antenna and by the second antenna;

generating a sum signal by adding the split first non-modulated signal received by the first antenna and the split first non-modulated signal received by the second antenna; and

comparing the sum signal with the split first non-modulated signal received by the first antenna and with the split first non-modulated signal received by the second antenna to determine a phase difference between the sum signal and the split signals.

14. The method of claim 13, further comprising:

transmitting the position of the vehicle on the guideway to an external control system.

15. The method of claim 13, further comprising:

detecting a position of the vehicle relative to a second reflective positioning element along the guideway, the closest transponder being located a second known distance along the guideway from the second reflective positioning element; and

determining a heading of the vehicle based on the modulated reflection signal, a second non-modulated reflection signal received from the second reflective positioning element, the first known distance, and the second known distance.

16. The method of claim 15, wherein the heading is further based on a determination of an order by which the first non-modulated reflection signal and the second non-modulated reflection signal are received.

17. The method of claim 13, wherein detecting the position of the vehicle relative to the first reflective positioning element comprises detecting the position of the vehicle relative to a half-wavelength reflector.

18. The method of claim 13, further comprising:

receiving update information from an external control system; and

updating a transponder identification database of the position determining system using the update information.

19. The method of claim 13, further comprising:

determining the vehicle is directly over the first reflective positioning element if the phase difference is equal to zero and the sum signal is at a maximum amplitude.

20. The method of claim 13, further comprising:

determining a difference between the split first non-modulated signal received by the first antenna and the split first-modulated signal received by the second antenna,

wherein the phase difference is based on the sum signal and the difference between the split first non-modulated signal received by the first antenna and the split first-modulated signal received by the second antenna.