Method and system for wear control of vehicle tyres

• US 8,775,017 B2
• Filed: 10/22/2009
• Issued: 07/08/2014
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Pirelli Tyre SPA (Pirelli & C SPA)
• Original Assignee: Pirelli Tyre SPA (Pirelli & C SPA)
• Inventors: Brusarosco, Massimo, Mancosu, Federico
• Primary Examiner(s): Shafi, Muhammad
• Assistant Examiner(s): ALSOMIRI, MAJDI A
• Application Number:
  US13/125,552
• Publication Number:
  US 20110202228A1
• Time in Patent Office: 1,720 Days
• Field of Search: 701 291- 344, 702/33, 702/34, 702/41, 702/127, 702/150, 702/151, 340438-447, 73146-1465, 152151-1542, 152208-20926
• US Class Current: 701/33.7
• CPC Class Codes: B60C 11/24 Wear-indicating arrangements
• CPC Class Codes: B60C 11/243 Tread wear sensors, e.g. electronic sensors
• CPC Class Codes: B60C 11/246 Tread wear monitoring systems
• CPC Class Codes: Y10T 152/10027 with wear indicating feature

Abstract

A method for wear control of vehicle tires, includes: detecting deformation of an inner surface of a first tire by means of a first sensor; determining a first level of wear of the first tire; detecting a deformation of an inner surface of a second tire by means of a second sensor; determining a second level of wear of the second tire; comparing the first and second levels of wear with each other; and generating a notification signal representative of the comparison. Also disclosed is a system for wear control of vehicle tires, a method of determining the wear of a tire and a system for determining the wear of a tire.

Claims

1. A method of determining wear of a tyre using a processing unit, wherein said tyre rolls on a rolling surface, a footprint area being defined between the tyre and said rolling surface, the method comprising:

detecting a first signal representative of a deformation of an inner surface of the tyre;

identifying at least one first portion comprised within said first signal using the processing unit, said first portion being representative of said deformation in a detection region which is external to the footprint area and substantially contiguous to the footprint area in the rotation direction of the tyre; and

processing at least said first portion of said first signal using the processing unit so as to determine at least one parameter representative of the wear of said tyre, wherein said comprises filtering said first signal in a first frequency band in the range of between 700 Hz and 2000 Hz.

2. The method as claimed in claim 1, wherein said detection region comprises a pre-footprint region that is substantially contiguous to the footprint area and precedes the footprint area in a rotation direction of the tyre.

3. The method as claimed in claim 2, wherein said pre-footprint region has a first longitudinal end and a second longitudinal end, said first and second longitudinal ends defining a central angle of a width between 25°

and 65°

.

4. The method as claimed in claim 3, wherein the first and second longitudinal ends of said pre-footprint region define a central angle of a width of between 40°

and 50°

.

5. The method as claimed in claim 2, wherein the first portion of said first signal is representative of the deformation of the inner surface of the tyre in the pre-footprint region.

6. The method as claimed in claim 1, wherein the first portion of said first signal is representative of an acceleration corresponding to the deformation of said inner surface of the tyre in the detection region.

7. The method as claimed in claim 6, wherein the first portion of said first signal is representative of an acceleration corresponding to radial or tangential deformation of said inner surface of the tyre in the detection region.

8. The method as claimed in claim 1, further comprising sampling said first signal.

9. The method as claimed in claim 1, wherein said first frequency band is between 1000 Hz and 1700 Hz.

10. The method as claimed in claim 1, further comprising determining a first parameter (WOL_PRE) as a function of a mean value of amplitudes of said first signal in the first portion, the wear of said tyre being determined as a function of said first parameter (WOL_PRE).

11. The method as claimed in claim 10, wherein said first parameter (WOL_PRE) is a function of a root mean square value of the amplitude of said first signal in the first portion.

12. The method as claimed in claim 11, further comprising sampling said first signal, wherein said first parameter (WOL_PRE) is calculated according to the formula:

13. The method as claimed in claim 12, wherein said detection region further comprises a post-footprint region that is substantially contiguous to the footprint area and subsequent thereto in a rotation direction of the tyre, further comprising:

selecting in said first signal a second portion representative of a deformation of an inner surface of the tyre in the post-footprint region; and

determining the wear of said tyre from processing of said first and second portions of said first signal.

14. The method as claimed in claim 13, wherein said post-footprint region has a first longitudinal end and a second longitudinal end, said first and second longitudinal ends defining a central angle of a width between 25°

and 65°

.

15. The method as claimed in claim 14, wherein the first and second longitudinal ends of said post-footprint region define a central angle of a width between 40°

and 50°

.

16. The method as claimed in claim 13, wherein the second portion of said first signal is representative of an acceleration corresponding to the deformation of said inner surface of the tyre in the post-footprint region.

17. The method as claimed in claim 16, wherein the second portion of said first signal is representative of an acceleration corresponding to radial or tangential deformation of said inner surface of the tyre in the post-footprint region.

18. The method as claimed in claim 13, further comprising determining a second parameter (WOL_POST) as a function of a mean value of the amplitudes of said first signal in the second portion, the wear of said tyre being determined as a function of a comparison between said first and second parameters (WOL_PRE, WOL_POST).

19. The method as claimed in claim 18, wherein said second parameter (WOL_POST) is a function of a root mean square value of amplitudes in the second portion of said first signal.

20. The method as claimed in claim 19, wherein said second parameter (WOL_POST) is calculated according to the formula

21. The method as claimed in claim 18, wherein the wear of said tyre is determined as a function of a difference between said first and second parameters (WOL_PRE, WOL_POST).

22. A system for determining a parameter representative of wear of a tyre, the system comprising:

a tyre adapted to roll on a rolling surface so as to define a footprint area between the tyre and said rolling surface, and a detection region that is external to the footprint area and substantially contiguous to the footprint area in the rotation direction of the tyre;

at least one sensor fitted on an inner surface of said tyre for detecting at least one first signal representative of a deformation of said inner surface of the tyre, said first signal comprising at least one first portion representative of said deformation in the detection region; and

a processing unit operatively associated with said sensor for receiving said first signal and capable of being adapted to identify and process at least said first portion of said first signal so as to determine at least one parameter representative of the wear of said tyre, wherein said processing unit comprises a filtering module for filtering said first signal a first frequency band included between 700 Hz and 2000 Hz.

23. The system as claimed in claim 22, wherein said detection region comprises a pre-footprint region that is substantially contiguous to the footprint area and precedes the footprint area in a rotation direction of the tyre.

24. The system as claimed in claim 23, wherein said pre-footprint region has a first longitudinal end and a second longitudinal end, said first and second longitudinal ends defining a central angle of a width between 25°

and 65°

.

25. The system as claimed in claim 24, wherein the first and second longitudinal ends of said pre-footprint region define a central angle of a width between 40°

and 50°

.

26. The system as claimed in claim 22, wherein the first portion of said first signal is representative of an acceleration corresponding to the deformation of said inner surface of the tyre in the detection region.

27. The system as claimed in claim 26, wherein the first portion of said first signal is representative of an acceleration corresponding to radial or tangential deformation of said inner surface of the tyre in the detection region.

28. The system as claimed in claim 22, wherein the first portion of said first signal is representative of deformation of the inner surface of the tyre in the pre-footprint region.

29. The system as claimed in claim 22, wherein said processing unit further comprises a sampling module for sampling said first signal.

30. The system as claimed in claim 22, wherein said first frequency band is between 1000 Hz and 1700 Hz.

31. The system as claimed in claim 22, wherein said processing unit comprises a first computing module for determining a first parameter (WOL_PRE) as a function of a mean value of amplitudes of said first signal in the first portion.

32. The system as claimed in claim 31, wherein said first parameter (WOL_PRE) is a function of root mean square value of amplitudes of said first signal in the first portion.

33. The system as claimed in claim 32, further comprising a sampling module for sampling said first signal, wherein said first parameter (WOL_PRE) is calculated according to the formula:

34. The system as claimed in claim 33, wherein said detection region comprises a post-footprint region that is substantially contiguous to the footprint area and subsequent to the footprint area in a rotation direction of the tyre, said processing unit further comprising a second selection module capable of being adapted to select a second portion in said first signal which second portion is representative of the deformation of the inner surface of the tyre in the post-footprint region and to determine wear of said tyre through processing of said first and second portions of said first signal.

35. The system as claimed in claim 34, wherein said post-footprint region has a first longitudinal end and a second longitudinal end and a second longitudinal end, said first and second longitudinal ends defining a central angle of a width between 25°

and 65°

.

36. The system as claimed in claim 35, wherein the first and second longitudinal ends of said post-footprint region define a central angle of a width between 40°

and 50°

.

37. The system as claimed in claim 34, wherein the second portion of said first signal is representative of an acceleration corresponding to the deformation of said inner surface of the tyre in the post-footprint region.

38. The system as claimed in claim 37, wherein the second portion of said first signal is representative of an acceleration corresponding to radial or tangential deformation of said inner surface of the tyre in the post-footprint region.

39. The system as claimed in claim 34, wherein said processing unit further comprises a second computing module capable of being adapted to determine a second parameter (WOL_POST) as a function of a mean value of amplitudes of said first signal in the second portion of said first signal.

40. The system as claimed in claim 39, wherein the wear said tyre is determined as a function of a difference between said first and second parameters (WOL_PRE, WOL_POST).

41. The system as claimed in claim 34, wherein said second parameter (WOL_POST) is a function of a root mean square value of amplitudes of said first signal in the second portion.

42. The system as claimed in claim 41, wherein said second parameter (WOL_POST) is calculated according to the formula:

43. The system as claimed in claim 22, wherein said processing unit is positioned on board a vehicle on which said tyre is fitted.