Determination of wheel sensor position using a single radio frequency detector in an automotive remote tire monitor system

• US 20060017554A1
• Filed: 04/13/2005
• Published: 01/26/2006
• Est. Priority Date: 10/29/2001
• Status: Active Grant

• Current Assignee: Sensata Technologies Incorporated (Sensata Technologies Holding Plc)
• Original Assignee: Schrader-Bridgeport International Incorporated (Pacific Industrial Company Limited)
• Inventors: Boudaoud, Idir, Stewart, William David, McClelland, Thomas David Stephen
• Granted Patent: US 7,423,532 B2
• Time in Patent Office: Days
• US Class Current: 340/447
• CPC Class Codes: B60C 23/0416 allocating a corresponding wheel position on vehicle, e.g. front/left or rear/right
• CPC Class Codes: B60C 23/0444 Antenna structures, control or arrangements thereof, e.g. for directional antennas, diversity antenna, antenna multiplexing or antennas integrated in fenders

Abstract

A tire monitor system employs a single RF detector mounted on the vehicle. The tire monitor system also includes a control unit and a receiver. The single RF detector is positioned to be proximate a front axle or a rear axle. The RF detector also may be positioned off-center. The control unit distinguishes front tire monitors from rear tire monitors by comparing a number of RF transmissions received by each tire monitor. The control unit also may distinguish between left tire monitors and right tire monitors by comparing the number of RF transmissions received by each tire monitor. In other embodiment, the tire monitor system may further use a received signal strength and/or acceleration signals to determine position information of the tire monitors.

Claims

1. A remote tire monitor system, comprising:

a plurality of tire monitors associated with wheels of a vehicle and operable to transmit tire information;

a single radio frequency (RF) detector operable to detect a RF transmission from two or more tire monitors and produce a detected transmission indication;

a receiver operable to receive the tire information; and

a control unit coupled with the RF detector and the receiver, the control unit operable to determine positions of the plurality of tire monitors based on the detected transmission indication and the received tire information.

2. The remote tire system of claim 1, wherein the control unit is operable to count the detected transmission indication and associate the plurality of tire monitors with front versus rear position based on a count value.

3. The remote tire system of claim 1, wherein the control unit is operable to count the detected transmission indication and associate the plurality of tire monitors with left versus right position based on the count value.

4. The remote tire system of claim 2, wherein the control unit is operable to compare count values of the received detected transmission indication for the plurality of tire monitors and determine left versus right position for the plurality of tire monitors associated with the front versus rear position.

5. The remote tire monitor system of claim 4, wherein the control unit is operable to store a distance between the detector and each tire monitor and associate the distance information with the count values.

6. The remote tire monitor system of claim 1, wherein the detector is positioned off-center and proximate either a front axle or a rear axle.

7. A remote tire monitor system for use with a vehicle having a front side, a rear side, a left side and a right side, comprising:

a plurality of tire monitors associated with each side of the vehicle and operable to transmit tire information;

a single radio frequency (RF) detector positioned proximate one side of the vehicle and generate a transmission indication in response to radio frequency (RF) transmissions from at least one of the plurality of tire monitors;

a receiver operable to receive the tire information; and

a control unit coupled with the RF detector and the receiver, the control unit operable to determine positions of the plurality of tire monitors based on the transmission indication and the tire information.

8. The remote tire monitor system of claim 7, wherein the detector is positioned proximate either the front side or the rear side and operable to detect RF transmissions from tire monitors proximate the detector.

9. The remote tire monitor system of claim 7, wherein the detector is positioned proximate either the left side or the right side and operable to detect RF transmissions from tire monitors proximate the detector.

10. The remote tire monitor system of claim 8, wherein the control unit is operable to evaluate a received signal strength for each transmission from the plurality of tire monitors.

11. The remote tire monitor system of claim 10, wherein the control unit is operable to determine front versus rear position information based on the detected transmission indication and left versus right position information based on the received signal strength.

12. The remote tire monitor system of claim 10, wherein the control unit is configured to detect a malfunctioning of the detector and determine front versus rear position information and left versus right position information based on the received signal strength upon detection of the malfunctioning.

13. The remote tire monitor system of claim 8, wherein each tire monitor includes an acceleration sensor to detect acceleration values and generate an acceleration signal for the acceleration values and the control unit is operable to evaluate the acceleration signal for each transmission from the plurality of tire monitors.

14. The remote tire system of claim 13, wherein the control unit is operable to determine front versus rear position information based on the transmission indication and left versus right position information based on a polarity of the acceleration signal.

15. The remote tire system of claim 13, wherein the control unit is operable to determine front versus rear position information based on the transmission indication and left versus right position information based on lead/lag relationship of the acceleration signal.

16. A tire monitor method for use with a vehicle having a front side, a rear side, a left side and a right side, the method comprising:

positioning a single radio frequency (RF) detector proximate one side of the vehicle;

at the single RF detector, detecting RF transmissions from at least one of a plurality of tire monitors associated with each side of the vehicle;

at a receiver, receiving tire data from the plurality of tire monitors; and

at a control unit, determining positions of the plurality of tire monitors based on the detected RF transmissions and the tire data.

17. The tire monitor method of claim 16, further comprising:

at the control unit, counting a number of detected transmissions from each tire monitor;

processing the received tire data to extract an identifier of each tire monitor; and

associating the identifier with the number of detected transmission.

18. The tire monitor method of claim 17, further comprising:

at the control unit, comparing the number of detected transmissions among the plurality of tire monitors; and

selecting at least one identifier having a greater number of the detected transmissions than the rest of the tire monitors.

19. The tire monitor method of claim 18, further comprising:

assigning the selected identifier to at least one tire monitor proximate the single RF detector; and

assigning the remaining identifiers to at least one tire monitor distal from the signal RF detector.

20. The tire monitor method of claim 16, wherein detecting transmissions comprises:

detecting the transmissions from tire monitors proximate the single RF detector; and

detecting no transmissions from tire monitors distal from the single RF detector.

21. The tire monitor method of claim 20, further comprising:

selecting a first identifier associated with the detected transmissions;

selecting a second identifier associated with no transmissions;

assigning the first identifier to the tire monitors proximate the RF detector and assigning the second identifier to the tire monitors distal from the RF detector.

22. The tire monitor method of claim 21, further comprising:

at the control unit, determining a received signal strength from each tire monitor;

determining a left versus right position of the tire monitors proximate the front side based on the received signal strength; and

determining the left versus right position of the tire monitors proximate the rear side based on the received signal strength.

23. The tire monitor method of claim 21, further comprising:

at the control unit, determining a received signal strength from each tire monitor;

determining a front versus rear position of the tire monitors proximate the left side based on the received signal strength; and

determining the front versus rear position of the tire monitors proximate the right side based on the received signal strength.

24. The tire monitor method of claim 21, further comprising:

at the tire monitors, generating acceleration signals representing acceleration values that arise from rotation of wheels;

at the control unit, evaluating a polarity of the acceleration signals; and

determining a left versus right position of the tire monitors based on the polarity of the acceleration.

25. The tire monitor method of claim 21, further comprising:

at the tire monitors, generating acceleration signals representing acceleration values that arise from rotation of wheels;

at the control unit, evaluating a polarity of the acceleration signals; and

determining a front versus rear position of the tire monitors based on the polarity of the acceleration.

26. The tire monitor method of claim 21, further comprising:

at the tire monitors, generating acceleration signals representing acceleration values that arise from rotation of wheels;

at the control unit, evaluating lead/lag relationship of the acceleration signals; and

determining a left versus right position of the tire monitors based on the lead/lag relationship of the acceleration.

27. The tire monitor method of claim 21, further comprising:

at the tire monitors, generating acceleration signals representing acceleration values that arise from rotation of wheels;

at the control unit, evaluating lead/lag relationship of the acceleration signals; and

determining a front versus rear position of the tire monitors based on the lead/lag relationship of the acceleration.

28. The tire monitor method of claim 16, further comprising:

positioning the single detector to be off-center and proximate one of the front axle and the rear axle.

29. The tire monitor method of claim 28, further comprising:

at the control unit, comparing the number of detected transmissions among the plurality of tire monitors;

assigning the identifier having the greatest number of detected transmissions to a tire monitor proximate the single RF detector; and

assigning the identifier having the smallest number of detected transmissions to a tire monitor distal from the signal RF detector.