Trailer wheel targetless trailer angle detection

• US 10,046,800 B2
• Filed: 08/10/2016
• Issued: 08/14/2018
• Est. Priority Date: 08/10/2016
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Hu, Zheng, Lavoie, Erick Michael
• Primary Examiner(s): Liu, Li
• Application Number:
  US15/233,458
• Publication Number:
  US 20180043933A1
• Time in Patent Office: 734 Days
• CPC Class Codes: B60R 11/04 Mounting of cameras operative during drive; Arrangement of controls thereof relative to the vehicle
• CPC Class Codes: B62D 13/06 for backing a normally drawn trailer
• CPC Class Codes: B62D 15/027 Parking aids, e.g. instruction means
• CPC Class Codes: G06V 10/443 by matching or filtering
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle
• CPC Class Codes: G06V 20/58 Recognition of moving objects or obstacles, e.g. vehicles or pedestrians; Recognition of traffic objects, e.g. traffic signs, traffic lights or roads

Abstract

A backup assist system for a vehicle and trailer combination includes a steering system, a camera generating an image of the trailer, and a controller. The controller receives the image and identifying a wheel therein, determines a value in a kinematic model of the vehicle and trailer combination using at least one of an aspect ratio or location of the wheel in the image, and uses the value in the kinematic model to control the steering system.

Claims

1. A backup assist system for a vehicle and trailer combination, comprising:

a steering system;

a camera generating an image of the trailer; and

a controller;

receiving the image and identifying a wheel therein;

determining a value in a kinematic model of the vehicle and trailer combination using an aspect ratio of the wheel in the image; and

using the value in the kinematic model to control the steering system.

2. The system of claim 1, wherein the camera is positioned on a side of the vehicle and the wheel is a trailer wheel on a side of the trailer corresponding to the side of the vehicle.

3. The system of claim 1, wherein the value is a length of the trailer.

4. The system of claim 1, wherein the value is a trailer hitch angle.

5. The system of claim 4, wherein the trailer hitch angle is determined as a sum of:

a projection angle of the wheel calculated using the aspect ratio of the wheel; and

a view angle of the wheel relative to the camera derived from the location of the wheel within the image.

6. The system of claim 4, wherein the trailer hitch angle is continuously determined from sequential images of the trailer generated by and received from the camera during control of the system in a trailer backup control operation.

7. The system of claim 1, wherein using the value in the kinematic model to control the steering system includes outputting a steering command determined, using the kinematic model, to maintain the trailer along a predetermined path.

8. The system of claim 7, wherein the predetermined path has a curvature corresponding with a user input curvature command.

9. A vehicle, comprising:

a steering system;

a camera generating images of a predetermined area to a rear of the vehicle; and

a system for assisting in reversing the vehicle with a trailer coupled therewith and including a controller;

processing sequential images received from the camera to identify a wheel and determine an aspect ratio of a wheel therein;

determining a value for an unknown in a kinematic model of the vehicle and trailer combination using the aspect ratio; and

using the value in the kinematic model to control the steering system.

10. The vehicle of claim 9, wherein the variable is a length of the trailer.

11. The vehicle of claim 9, wherein the unknown is a trailer hitch angle.

12. The vehicle of claim 11, wherein the trailer hitch angle is determined as a sum of:

a projection angle of the wheel calculated using the aspect ratio of the wheel; and

a view angle of the wheel relative to the camera derived from the location of the wheel within the predetermined area.

13. The vehicle of claim 11, wherein the trailer hitch angle is continuously determined from the sequential images of the trailer during control of the system in a trailer backup control operation.

14. The vehicle of claim 9, wherein the camera is positioned on a side of the vehicle and the wheel is a trailer wheel on a side of the trailer corresponding to the side of the vehicle.

15. The vehicle of claim 9, wherein using the value in the kinematic model to control the steering system includes outputting a steering command determined, using the kinematic model, to maintain the trailer along a predetermined path having a curvature corresponding with a user input curvature command.

16. A method for assisting a vehicle in reversing a trailer, comprising:

using a processor to;

identify a wheel of the trailer and to determine an aspect ratio thereof within an image received from a camera; and

determine a value in a kinematic model of the vehicle and trailer combination using the aspect ratio; and

using the value in the kinematic model to control a steering system of the vehicle.

17. The method of claim 16, wherein the value is a trailer hitch angle.

18. The method of claim 17, wherein the trailer hitch angle is determined as a sum of:

a projection angle of the wheel calculated using the aspect ratio of the wheel; and

a view angle of the wheel relative to the camera derived from the position of the wheel within the image.

19. The method of claim 18, wherein the trailer hitch angle is continuously determined from the sequential images of the trailer during control of the steering system in a trailer backup control operation.

20. The method of claim 16, wherein using the value in the kinematic model to control the steering system includes outputting a steering command determined, using the kinematic model, to maintain the trailer along a predetermined path having a curvature corresponding with a user input curvature command.