Target-based trailer backup collision mitigation
A backup assist system for a vehicle and trailer combination includes a vehicle steering system, a camera generating images of the trailer, and a controller. The controller processes sequential images the trailer, selects a baseline image, and determines a collision angle based on a location of a feature of the trailer in the baseline image. The controller further controls the steering system to maintain a hitch angle below a lesser of a maximum controllable angle and the collision angle.
1. A backup assist system for a vehicle and trailer combination, comprising:
a vehicle steering system;
a camera generating images of the trailer; and
a controller:
processing sequential images of the trailer during a straight driving interval;
selecting a baseline image corresponding with a determined steady-state condition;
determining a vehicle-trailer collision angle based on a location of a feature of the trailer in the baseline image; and
controlling the steering system to maintain a hitch angle at or below a maximum controllable angle or below the collision angle, whichever is lesser.
2. The system of claim 1 , wherein the controller further determines the hitch angle by comparing an instantaneous one of the sequential images and the baseline image.
3. The system of claim 1 , wherein the camera is mounted on the vehicle facing toward the trailer.
4. The system of claim 1 , wherein the maximum controllable angle is determined by the controller using a kinematic model of the vehicle and trailer combination.
5. The system of claim 1 , wherein the collision angle is based on an angle between the feature of the trailer and an adjacent corner of the vehicle.
6. The system of claim 5 , wherein the collision angle further includes a safety angle added to the angle between the feature of the trailer and the adjacent corner of the vehicle.
7. The system of claim 5 , wherein the feature is a checkered target.
8. The system of claim 7 , wherein:
the vehicle defines a first distance from a trailer hitch with which the trailer is coupled to an adjacent corner of the vehicle; and
wherein the target is positioned on the trailer at a second distance from the trailer hitch approximately equal to the first distance.
9. The system of claim 1 , wherein the controller further prompts a user to drive the vehicle and trailer combination along a straight path in a forward direction prior to selecting the baseline image.
10. 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 during a straight driving interval;
selecting a baseline image of the trailer, including a locating feature, corresponding with a determined steady-state condition;
determining a vehicle-trailer collision angle based on a location of the feature in the baseline image; and
controlling the steering system to maintain a hitch angle at or below a maximum controllable angle or below the collision angle, whichever is lesser.
11. The vehicle of claim 10 , wherein controlling the controller further determines the hitch angle by comparing an instantaneous one of the sequential images and the baseline image.
12. The vehicle of claim 10 , wherein the camera is mounted on the vehicle facing toward the trailer.
13. The vehicle of claim 10 , wherein the maximum controllable angle is determined by the controller using a kinematic model of a combination of the vehicle and the trailer.
14. The vehicle of claim 10 , wherein the collision angle is based on an angle between the feature of the trailer and an adjacent corner of the vehicle.
15. The vehicle of claim 14 , wherein the collision angle further includes a safety angle added to the angle between the feature of the trailer and the adjacent corner of the vehicle.
16. A method for assisting a vehicle in reversing a trailer, comprising:
selecting a baseline image from a plurality of sequential images received from a camera mounted to the vehicle during a straight driving interval;
determining a vehicle-trailer collision angle based on a location of a target on the trailer in the baseline image corresponding with a determined steady-state condition; and
controlling a steering system of the vehicle to maintain a trailer hitch angle at or below a maximum controllable angle or below the collision angle, whichever is lesser.
17. The method of claim 16 , wherein the hitch angle is determined by comparing an instantaneous location of the target in an instantaneous one of the sequential images and a location of the target in the baseline image.
18. The method of claim 16 , wherein the maximum controllable angle is determined using a kinematic model of the vehicle and trailer combination.
19. The method of claim 16 , wherein the collision angle is based on an angle between the target and an adjacent corner of the vehicle.
20. The method of claim 16 , further including prompting a user to drive the vehicle along a straight path in a forward direction for one of a predetermined time interval or a predetermined distance prior to selecting the baseline image.