WHEEL SLIP OR SPIN NOTIFICATION

• US 20150131864A1
• Filed: 11/13/2013
• Published: 05/14/2015
• Est. Priority Date: 11/13/2013
• Status: Active Grant

• Current Assignee: Elwha LLC (Intellectual Ventures LLC)
• Original Assignee: Elwha LLC (Intellectual Ventures LLC)
• Inventors: Driscoll, Tom, Hannigan, Russell J., Hyde, Roderick A., Ishikawa, Muriel Y., Kare, Jordin T., Myhrvold, Nathan P., Smith, David R., Tegreene, Clarence T., Urzhumov, Yaroslav A., Whitmer, Charles, Wood, Lowell L. Jr., Wood, Victoria Y. H., Guerci, Joseph R.
• Granted Patent: US 9,412,028 B2
• Time in Patent Office: Days
• US Class Current: 382/104
• CPC Class Codes: B60W 2050/0031 Mathematical model of the vehicle
• CPC Class Codes: B60W 2420/403 Image sensing, e.g. optical camera
• CPC Class Codes: B60W 2555/00 Input parameters relating to exterior conditions, not covered by groups B60W2552/00, B60W2554/00
• CPC Class Codes: B60W 40/068 Road friction coefficient
• CPC Class Codes: B60W 40/10 related to vehicle motion
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle

Abstract

Described embodiments include a system and method. A digital imaging device is configured to capture images of a region of a contact between a wheel of a terrestrial vehicle and a surface (“contact region”). A correlator is configured to correlate a first digital image of the contact region captured at a first time with a second digital image of the contact region captured at a second time. A kinematics circuit determines an incremental slide or slip of the wheel relative to the surface. A fraction status circuit combines at least two instances of the incremental slide or slip into data indicative of a slide or slip by the terrestrial vehicle relative to the surface. A communications circuit outputs an electronic signal indicative of the data indicative of a slide or slip by the terrestrial vehicle.

Claims

1. A system comprising:

a digital image correlator configured to (i) correlate a first digital image having a field of view that includes a portion of a wheel of a terrestrial vehicle in contact with a stochastic surface traveled by the vehicle and that also includes a portion of the stochastic surface proximate to the contact with the wheel (hereafter “

contact region”

) captured at a first time with a second digital image of the contact region captured at a subsequent second time, and (ii) determine a correlation vector.

a kinematics circuit configured to determine responsive to the correlation vector an incremental slide or slip of the wheel relative to the stochastic surface;

a traction status circuit configured to combine at least two instances of the incremental slide or slip of the wheel into data indicative of a slide or slip by the terrestrial vehicle relative to the stochastic surface during a period of time; and

a communications circuit configured to output an electronic signal indicative of the data indicative of a slide or slip by the terrestrial vehicle relative to the stochastic surface over the period of time.

2. The system of claim 1, further comprising:

a digital imaging device configured to capture multiple pixel two-dimensional digital images.

3. The system of claim 1, wherein the contact region includes at least a portion of the stochastic surface and at least a portion of the wheel beyond the region of physical contact between the wheel and the stochastic surface.

4. The system of claim 1, wherein the contact region includes a portion of a tire carried by the wheel proximate to where the tire and the stochastic surface are in physical contact.

5. The system of claim 1, wherein the contact region includes a portion of the stochastic surface proximate to where a tire carried by the wheel and the stochastic surface are in physical contact.

6. The system of claim 1, wherein the kinematics circuit includes a model of the vehicle dynamics.

7. The system of claim 6, wherein the model of the vehicle dynamics includes an at least partially learned model of the vehicle dynamics.

8. The system of claim 7, wherein the at least partially learned model of the vehicle dynamics is responsive to at least two previously determined correlation vectors.

9. The system of claim 1, wherein the traction status circuit is further configured to combine at least two instances of the incremental slide or slip of the wheel into data indicative of a driving hazard level.

10. The system of claim 9, wherein the driving hazard level includes a first hazard level indicative of a low or no diving hazard and a second hazard level indicative of a high driving hazard.

11. The system of claim 1, wherein the communications circuit is configured to output an electronic signal indicative of the data indicative of a slide or slip by the wheel relative to the stochastic surface over the period of time in a format usable by an operations controller of the vehicle.

12. The system of claim 1, wherein the communications circuit is configured to output an electronic signal indicative of the data indicative of a slide or slip by the wheel relative to the stochastic surface over the period of time in a format usable by a traction controller of the vehicle.

13. The system of claim 1, wherein the wheel includes at least two discrete marks arranged circumferentially on the wheel and discernible by the digital image correlator.

14. The system of claim 1, further comprising:

a display device configured to display a human perceivable presentation of the data indicative of a slide or slip by the vehicle relative to the stochastic surface during a period of time.

15. A method comprising:

capturing at a first time a first digital image having a field of view that includes a portion of a wheel of a terrestrial vehicle in contact with a stochastic surface traveled by the vehicle and that also includes a portion of the stochastic surface proximate to the contact with the wheel (hereafter “

contact region”

);

capturing at a subsequent second time a second digital image of the contact boundary region;

correlating the first digital image with the second digital image and determining a correlation vector;

determining responsive to the correlation vector an incremental slide or slip of the wheel relative to the stochastic surface;

combining at least two instances of the incremental slide or slip of the wheel into data indicative of a slide or slip by the terrestrial vehicle relative to the stochastic surface during a period of time; and

outputting an electronic signal indicative of the data indicative of a slide or slip by the terrestrial vehicle relative to the stochastic surface over the period of time.

16. The method of claim 15, wherein the combining further includes combining at least two instances of the incremental slide or slip of the wheel into data indicative of a driving hazard level.

17. The method of claim 15, further comprising:

transforming the data into a particular human-perceivable depiction of the slide or slip by the wheel relative to the stochastic surface over the period of time.

18. The method of claim 15, further comprising:

illuminating at least a portion of the stochastic surface during a capture of digital image.

19. A system comprising:

means for capturing (i) at a first time a first digital image having a field of view that includes a portion of a wheel of a terrestrial vehicle in contact with a stochastic surface traveled by the vehicle and that also includes a portion of the stochastic surface proximate to the contact with the wheel (hereafter “

contact region”

), and (ii) at a subsequent second time a second digital image of the contact region;

means for correlating the first digital image with the second digital image and determining a correlation vector;

means for determining responsive to the correlation vector an incremental slide or slip of the wheel relative to the stochastic surface;

means for combining at least two instances of an incremental slide or slip by the wheel into data indicative of a slide or slip by the terrestrial vehicle relative to the stochastic surface during a period of time; and

means for outputting an electronic signal indicative of the data indicative of a slide or slip by the terrestrial vehicle relative to the stochastic surface over the period of time.

20. The system of claim 19, wherein the means for combining includes means for combining at least two instances of the incremental slide or slip of the wheel into data indicative of a driving hazard level.

21. The system of claim 19, further comprising:

means for transforming the data into a particular human-perceivable depiction of the slide or slip by the terrestrial vehicle relative to the stochastic surface over the period of time.