METHOD FOR DETECTING WHEEL ROTATION USING A ONE-DIMENSIONAL ACCELERATION SENSOR

• US 20130085710A1
• Filed: 09/30/2011
• Published: 04/04/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Kautzsch, Thoralf
• Granted Patent: US 10,017,015 B2
• Time in Patent Office: Days
• US Class Current: 702/141
• CPC Class Codes: B60C 23/0416 allocating a corresponding wheel position on vehicle, e.g. front/left or rear/right
• CPC Class Codes: B60C 23/0488 Movement sensor, e.g. for sensing angular speed, acceleration or centripetal force

Abstract

Embodiments relate to TPMS utilizing a single-axis acceleration sensor for measuring the direction of rotation of the tires in a tire localization methodology. In an embodiment, the known axis position of the acceleration sensor in the tires allows for the assessment by an integrated circuit in order to determine the left or right positioning of a tire, as well as the magnitude of acceleration or deceleration. Because of the dual components of the measured acceleration signal of first, the directional acceleration of the vehicle and second, the oscillating modulation due to gravity, the generated waveform is known to have differences between the left and right tire signals of an accelerating and decelerating vehicle. The impact of the oscillating modulation on the directional acceleration of the vehicle can be utilized to identify tire rotation direction, and thus the wheels localized therefrom, as well as the magnitude of acceleration and deceleration.

Claims

1. A method comprising:

determining an acceleration sensor profile for each of a plurality of wheels of a vehicle, wherein the profile defines at least an axis of orientation of the acceleration sensor relative to the wheel;

receiving a first acceleration data signal from at least one wheel module located on a first side of the vehicle and a second acceleration data signal from at least one wheel module located on a second side of the vehicle;

determining a zero-acceleration point between the first and second acceleration data signals; and

partially localizing, by identifying the location relative to the first and second sides, each of the wheel modules based on at least an evaluation of the acceleration sensor profile and the data signal.

2. The method of claim 1, further comprising fully localizing wheel modules based on a determination of front and rear wheels.

3. The method of claim 1, further comprising:

determining an offset based on the received first and second acceleration data signals as modulated by gravity; and

determining a difference in the offset of the first and second acceleration data signals from the determined zero acceleration point in order to determine a magnitude of acceleration.

4. The method of claim 1, wherein the acceleration sensor profile comprises a positive axis exposed for wheels mounted on one side when the vehicle moves in a forward direction.

5. The method of claim 1, wherein the acceleration sensor profile comprises a negative axis exposed for wheels mounted on one side when the vehicle moves in a forward direction.

6. The method of claim 2, further comprising sensing a pressure by the wheel module.

7. A method comprising:

receiving a first oscillated acceleration signal of a first wheel module;

receiving a second oscillated acceleration signal of a second wheel module; and

localizing the first and second wheel modules based on at least an evaluation of the first oscillated acceleration signal.

8. The method of claim 7, further comprising determining an acceleration of a vehicle based on a frequency of the first or second oscillated acceleration signals.

9. The method of claim 7, further comprising determining an acceleration of a vehicle based on an offset of the first oscillated acceleration signal and the second oscillated acceleration signal.

10. The method of claim 8, further comprising determining a magnitude of the acceleration of the vehicle based on the offset.

11. The method of claim 7, further comprising sensing a pressure by the wheel module.

12. A system comprising:

a plurality of wheel modules, each wheel module associated with a wheel of a vehicle and comprising an acceleration sensor configured to sense acceleration related to the wheel, wherein each acceleration sensor has a uniform acceleration sensor placement relative to the wheel, and each acceleration sensor has an acceleration sensor profile defining at least an axis of orientation of the acceleration sensor relative to the wheel such that wheels on opposite sides of the vehicle have opposite axes of orientation; and

a central receiver unit configured to receive signals from the plurality of wheel modules, the signals comprising acceleration data sensed by the acceleration sensor, and to partially localize each wheel of the vehicle by evaluating the received signals relative to the acceleration sensor profile.

13. The system of claim 12, wherein each of the plurality of wheel modules comprises a tire pressure monitoring system (TPMS) wheel module.

14. The system of claim 13, wherein each of the plurality of wheel modules further comprises a pressure sensor.

15. The system of claim 12, wherein the acceleration sensor for a wheel located on a first side of a vehicle is mounted such that a positive axis of the acceleration sensor is exposed when the vehicle moves in a forward direction, and the acceleration sensor for a wheel located on a second side of the vehicle is mounted such that a negative axis of the acceleration sensor is exposed when the vehicle moves in the forward direction.

16. The system of claim 12, wherein each of the plurality of wheel modules comprises a radio frequency (RF) communications unit.

17. A wheel module, the wheel module associated with a wheel of a vehicle, comprising:

an acceleration sensor configured to sense acceleration related to the wheel, the sensed acceleration being oscillated by gravity when the wheel is in motion, and the acceleration sensor having an acceleration sensor profile defining at least an axis of orientation of the acceleration sensor relative to the wheel;

a communications unit configured to receive acceleration data from a second wheel module;

a microcontroller configured to accumulate data from the acceleration sensor and partially localize the wheel module relative to the second wheel module based on the acceleration sensor profile and the accumulated sensor data; and

a power source configured to provide power to at least the acceleration sensor, microcontroller, and communications unit.

18. The wheel module of claim 17, wherein the microcontroller is further configured to partially localize the wheel module relative to the second wheel module by further determining a zero-acceleration point between the accumulated acceleration sensor data and the second wheel module acceleration data, and determining an offset between the accumulated acceleration sensor data and the second wheel module acceleration data.

19. The wheel module of claim 17, further comprising a pressure sensor configured to sense pressure of the wheel, wherein the microcontroller is further configured to accumulate data from the pressure sensor and the power source is further configured to provide power to the pressure sensor;

20. The wheel module of claim 17, further comprising a temperature sensor configured to sense the temperature of the wheel, wherein the microcontroller is further configured to accumulate data from the temperature sensor and the power source is further configured to provide power to the temperature sensor.

21. The wheel module of claim 17, wherein the acceleration sensor is a single-axis acceleration sensor.

22. The wheel module of claim 21, wherein the acceleration sensor is in a decentered location relative to the wheel.

23. A wheel module, the wheel module associated with a wheel of a vehicle, comprising:

an acceleration sensor configured to sense acceleration related to the wheel, the sensed acceleration being oscillated by gravity when the wheel is in motion, and the acceleration sensor having a fixed-orientation mounting position relative to the wheel;

a microcontroller configured to accumulate data from the acceleration sensor;

a communications unit configured to transmit data from the microcontroller to a central receiver unit to partially localize the wheel module relative to the vehicle based on the acceleration mounting position and the data accumulated from the acceleration sensor; and

a power source configured to provide power to at least the acceleration sensor, microcontroller, and communications unit.

24. The wheel module of claim 23, wherein the communications unit is further configured to transmit data from the microcontroller to the central receiver unit to calculate a magnitude of acceleration based on the acceleration mounting position, a zero-acceleration point between the accumulated sensor data and acceleration data from a second wheel module, and an offset between the accumulated sensor data and acceleration data from the second wheel module;

25. The wheel module of claim 24, wherein the zero-acceleration point is calculated by a difference between the accumulated sensor data and the acceleration data from the second wheel module when no oscillation is present.

26. The wheel module of claim 25, wherein the offset is calculated by a difference between the accumulated sensor data and the acceleration data from the second wheel module when oscillation is present.