Method of sampling acceleration measurements of a motor vehicle wheel

• US 9,459,275 B2
• Filed: 10/08/2010
• Issued: 10/04/2016
• Est. Priority Date: 10/08/2010
• Status: Active Grant

• Current Assignee: Continental Automotive France (Continental AG), Continental Automotive GmbH (Continental AG)
• Original Assignee: Continental Automotive France (Continental AG), Continental Automotive GmbH (Continental AG)
• Inventors: Guinart, Nicolas
• Primary Examiner(s): TRAN, HUAN HUU
• Application Number:
  US13/825,677
• Publication Number:
  US 20130179113A1
• Time in Patent Office: 2,188 Days
• US Class Current: 1/1
• CPC Class Codes: B60C 23/04 mounted on the wheel or tyre
• CPC Class Codes: B60C 23/0416 allocating a corresponding wheel position on vehicle, e.g. front/left or rear/right
• CPC Class Codes: B60C 23/0479 Communicating with external units being not part of the vehicle, e.g. tools for diagnostic, mobile phones, electronic keys or service stations
• CPC Class Codes: B60C 23/0488 Movement sensor, e.g. for sensing angular speed, acceleration or centripetal force
• CPC Class Codes: B60C 23/0489 for detecting the actual angular position of the monitoring device while the wheel is turning
• CPC Class Codes: G01P 15/165 for measuring angular accelerations

Abstract

A method of sampling acceleration measurements of a wheel (10, 20, 30, 40) of a motor vehicle (1), the vehicle (1) having a tire pressure monitoring system, and being fitted with an electronic central unit (2), each of the wheels (10, 20, 30, 40) including: a wheel unit (A, B, C, D) fixed to a rim (J10, J20, J30, J40) of radius R and having at least one accelerometer, measuring the radial acceleration F₁ of the wheel, and a microprocessor; the method including the measurement, for each wheel revolution, at given time intervals (T_measurement), of a number (N) of radial acceleration values by the radial accelerometer. The method proposes: that a minimum number (N) of acceleration measurements be fixed per wheel revolution, and that the time intervals (T_measurement) between two radial acceleration measurements be determined by element of the following relation:

$T_{\mathrm{measurement}}=\frac{2\pi ·\sqrt{\frac{R}{F_1}}}{N}$

Claims

1. A method of sampling acceleration measurements of a wheel (10, 20, 30, 40) of a motor vehicle (1), said vehicle (1) having a tire pressure monitoring system and being fitted with an electronic central unit (2), each of said wheels (10, 20, 30, 40) including:

a wheel unit (A, B, C, D) fixed to a rim (J10, J20, J30, J40) of radius R and having at least one accelerometer, measuring the radial acceleration F₁ of the wheel, and a microprocessor,

said method comprising;

measuring, for each wheel revolution, at given time intervals (T_measurement), a number (N) of radial acceleration values by the accelerometer;

fixing a minimum number (N) of acceleration measurements per wheel revolution;

determining the time intervals (T_measurement) between two radial acceleration measurements, using the following relation;

2. The location method as claimed in claim 1, wherein the accelerometer is a radial accelerometer.

3. The location method as claimed in claim 1, wherein, for a given rim radius (R), the number of acceleration measurements per wheel revolution (N) is fixed at 15.

4. The location method as claimed in claim 1, wherein, for an estimated rim radius (R), the number of acceleration measurements per wheel revolution (N) is greater than 15.

5. The location method as claimed in claim 1, wherein the acceleration measurements are filtered, by a high-pass and/or a low-pass filter, in order to eliminate the measurements caused by parasitic noise.

7. The location method as claimed in claim 2, wherein, for a given rim radius (R), the number of acceleration measurements per wheel revolution (N) is fixed at 15.

8. The location method as claimed in claim 2, wherein, for an estimated rim radius (R), the number of acceleration measurements per wheel revolution (N) is greater than 15.

9. The location method as claimed in claim 2, wherein the acceleration measurements are filtered, by a high-pass and/or a low-pass filter, in order to eliminate the measurements caused by parasitic noise.

10. The location method as claimed in claim 3, wherein the acceleration measurements are filtered, by a high-pass and/or a low-pass filter, in order to eliminate the measurements caused by parasitic noise.

11. The location method as claimed in claim 4, wherein the acceleration measurements are filtered, by a high-pass and/or a low-pass filter, in order to eliminate the measurements caused by parasitic noise.

6. A device for sampling acceleration measurements of a wheel (10, 20, 30, 40) of a motor vehicle (1), said vehicle (1) having a tire pressure monitoring system, and being fitted with an electronic central unit (2), each of said wheels including:

a wheel unit (A, B, C, D) fixed to a rim (J10, J20, J30, J40) of radius R and having at least one accelerometer, measuring radial acceleration F₁ of the wheel, and a microprocessor,

the accelerometer being configured to measure, for each wheel revolution, at given time intervals (T_measurement), a number (N) of radial acceleration values by the accelerometer;

said device comprising;

means for fixing a minimum number (N) of acceleration measurements per wheel revolution; and

means for determining time intervals (T_measurement) between two radial acceleration measurements, using the following relation;