Contact Patch Measurements During Hydroplaning Events

• US 20160264109A1
• Filed: 11/15/2013
• Published: 09/15/2016
• Est. Priority Date: 11/15/2013
• Status: Active Grant

• Current Assignee: Compagnie générale des établissements Michelin
• Original Assignee: Compagnie générale des établissements Michelin
• Inventors: Weston, David Alan
• Granted Patent: US 9,932,022 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60T 2210/13 Aquaplaning, hydroplaning
• CPC Class Codes: B60T 8/1725 Using tyre sensors, e.g. Sidewall Torsion sensors [SWT] for tyre pressure and temperature detection B60C23/00

Abstract

Systems and methods for determining the contact patch parameters of a tire while rolling on deformable surfaces, such as during a hydroplaning event, are provided. More particularly, a piezoelectric sensor configured to provide a piezoelectric sensor output signal indicative of the time-varying curvature of a rolling tire can be mounted in a tire. The piezoelectric sensor output signal can be analyzed to detect a signal perturbation corresponding to the hydroplaning event. One or more characteristics of the contact patch during the hydroplaning event can be analyzed based on the signal perturbation. For instance, a parameter indicative of the shape of the contact patch during the hydroplaning event can be assessed based on the signal perturbation.

Claims

1. A method of analyzing a contact patch of a tire during a hydroplaning event, comprising:

obtaining a piezoelectric sensor output signal from at least one piezoelectric sensor mounted in a tire, the piezoelectric sensor output signal being generated at least in part during a hydroplaning event;

analyzing, with one or more processing devices, the piezoelectric sensor output signal to determine a contact patch entry and a contact patch exit for the tire;

detecting, with the one or more processing devices, a signal perturbation corresponding to the hydroplaning event in the piezoelectric sensor output signal, the signal perturbation occurring between the contact patch entry and the contact patch exit; and

assessing a parameter of the contact patch based at least in part on the signal perturbation.

2. The method of claim 1, wherein the contact patch entry is determined by identifying a maximum slope in a first direction of the piezoelectric sensor output signal and the contact patch exit is determined by identifying a maximum slope in a second direction of the piezoelectric sensor output signal.

3. The method of claim 1, wherein detecting, with the one or more computing devices, a signal perturbation in the piezoelectric sensor output signal comprises analyzing, with one or more processing devices, the piezoelectric sensor output signal to identify an inflection point in the piezoelectric sensor output signal occurring between the contact patch entry and the contact patch exit.

4. The method of claim 1, wherein detecting, with the one or more computing devices, a signal perturbation in the piezoelectric sensor output signal comprises analyzing, with one or more processing devices, the piezoelectric sensor output signal to identify a first inflection point in the piezoelectric sensor output signal and a second inflection point in the piezoelectric sensor output signal, the first inflection point and the second inflection point occurring between the contact patch entry and the contact patch exit.

5. The method of claim 4, wherein the signal perturbation is detected based at least in part on the first inflection point and the second inflection point.

6. The method of claim 5, wherein a time associated with the signal perturbation is determined as an average of a time associated with the first inflection point and a time associated with a second inflection point.

7. The method of claim 1, wherein the parameter is indicative of a shape of the contact patch of the tire.

8. The method of claim 1, wherein the parameter comprises a quantitative degree of hydroplaning of the tire.

9. The method of claim 8, wherein quantitative degree of hydroplaning determined as follows:

10. The method of claim 1, wherein the method comprises detecting a hydroplaning event based at least in part on a rate of change of the piezoelectric sensor output signal at the second contact patch entry.

11. The method of claim 1, wherein obtaining a piezoelectric sensor output signal comprises obtaining a plurality of piezoelectric sensor output signals, each piezoelectric output sensor signal generated from one of a plurality of piezoelectric sensors mounted in the tire.

12. The method of claim 11, wherein the plurality of piezoelectric sensors are mounted across a lateral width of the tire.

13. The method of claim 11, wherein detecting, with the one or more processing devices, a signal perturbation corresponding to the hydroplaning event in the piezoelectric sensor output signal comprises detecting a plurality of signal perturbations, each signal perturbation associated with one of the plurality of piezoelectric sensor output signals.

14. The method of claim 13, wherein assessing a parameter of the contact patch based at least in part on the signal perturbation comprises determining one or more parameters indicative of a shape of the contact patch based at least in part on the plurality of signal perturbations.

15. A system for analyzing a contact patch of a tire during a hydroplaning event, comprising:

at least one piezoelectric sensor configured to generate a piezoelectric sensor output signal representative of a time varying curvature of a tire during tire rotation;

one or more processing devices, the one or more processing devices configured to execute computer-readable instructions stored in one or more computer readable media that when executed by the one or more processing devices cause the one or more processing devices to perform operations, the operations comprising any of the methods of the preceding claims.