Vehicle vision system with trailer angle detection

1. A vehicular vision system, said vehicular vision system comprising:

a camera disposed at a vehicle and having an exterior field of view rearward of the vehicle, wherein said camera is operable to capture image data;

an image processor operable to process captured image data;

wherein, when the vehicle is towing a trailer, and based at least in part on image processing of image data captured by said camera during maneuvering of the vehicle and the trailer, said image processor (i) estimates a distance between a hitching point of the trailer and an axle of the trailer, and (ii) estimates a length of the trailer that includes the estimated distance between the hitching point of the trailer and the axle of the trailer and an estimated distance between the axle of the trailer and a rear end portion of the trailer;

wherein image data captured by said camera during maneuvering of the vehicle and the trailer includes image data captured by said camera when the vehicle is maneuvered with the trailer at an angle relative to the vehicle;

wherein said vision system, responsive at least in part to image processing of captured image data, is operable to determine a trailer angle of the trailer that is towed by the vehicle; and

wherein said vision system is operable to determine a path of the trailer responsive to a steering angle of the vehicle and the determined trailer angle of the trailer and the estimated length of the trailer, and wherein said vision system is operable to display information for viewing by a driver of the vehicle to assist the driver in driving the vehicle with the trailer.

2. The vehicular vision system of claim 1 , wherein said vision system is operable to display images of a road in the direction of travel of the vehicle and the trailer and wherein said vision system is operable to display an overlay to indicate to the driver of the vehicle a steering path for the vehicle.

3. The vehicular vision system of claim 2 , wherein said vision system displays images of a road in the forward direction of travel of the vehicle and the trailer and wherein said overlay indicates a steering path for the vehicle that tows the trailer around an obstacle.

4. The vehicular vision system of claim 2 , wherein said vision system displays images of a road in the rearward direction of travel of the vehicle and the trailer and wherein said overlay indicates a steering path for the vehicle to drive the trailer into a selected location.

5. The vehicular vision system of claim 2 , wherein said overlay comprises markers that indicate a determined path of travel of the front wheels of the vehicle and a path of travel that the wheels of the trailer will follow if the driver of the vehicle steers the front wheels of the vehicle along the determined path of travel of the front wheels.

6. The vehicular vision system of claim 5 , wherein the determined path of travel of the front wheels of the vehicle is determined at least in part responsive to the steering angle of the vehicle.

7. The vehicular vision system of claim 1 , wherein said vision system is operable to determine the trailer's width by side camera image evaluation.

8. The vehicular vision system of claim 1 , wherein said vision system is operable to at least one of (a) estimate the trailer's tendency to oscillate when driving forward and (b) estimate the trailer's tendency to oscillate when driving forward and cope with that oscillation.

9. The vehicular vision system of claim 1 , wherein trailer data is input into said vision system to provide data pertaining to physical characteristics of the trailer, and wherein said vision system is operable to determine the path of the trailer at least in part responsive to the trailer data.

10. The vehicular vision system of claim 1 , wherein said vision system is operable to store properties of a certain trailer in a data file that is reloaded when that certain trailer is connected at the vehicle and identified by said vision system.

11. The vehicular vision system of claim 10 , wherein, responsive at least in part to image processing of captured image data, said vision system is operable to identify a trailer at the vehicle via identification of a trailer code element of the trailer that is viewable by said camera.

12. The vehicular vision system of claim 11 , wherein said trailer code element comprises a target having a Barker code pattern established thereon.

13. A vehicular vision system, said vehicular vision system comprising:

a camera disposed at a vehicle and having an exterior field of view rearward of the vehicle, wherein said camera is operable to capture image data;

an image processor operable to process captured image data;

wherein, when the vehicle is towing a trailer, and based at least in part on image processing of image data captured by said camera during maneuvering of the vehicle and the trailer, said image processor (i) estimates a distance between a hitching point of the trailer and an axle of the trailer, and (ii) estimates a length of the trailer that includes the estimated distance between the hitching point of the trailer and the axle of the trailer and an estimated distance between the axle of the trailer and a rear end portion of the trailer;

wherein image data captured by said camera during maneuvering of the vehicle and the trailer includes image data captured by said camera when the vehicle is maneuvered with the trailer at an angle relative to the vehicle;

wherein said vision system, responsive at least in part to image processing of captured image data, is operable to determine a trailer angle of the trailer that is towed by the vehicle;

wherein said vision system is operable to determine a path of the trailer responsive to a steering angle of the vehicle and the determined trailer angle of the trailer and the estimated length of the trailer, and wherein said vision system is operable to display information for viewing by a driver of the equipped vehicle to assist the driver in driving the vehicle with the trailer;

wherein said vision system is operable to display images of a road in the direction of travel of the vehicle and the trailer and wherein said vision system is operable to display an overlay to indicate to the driver of the vehicle a steering path for the vehicle;

wherein said overlay comprises markers that indicate a determined path of travel of the front wheels of the vehicle and a path of travel that the wheels of the trailer will follow if the driver of the vehicle steers the front wheels of the vehicle along the determined path of travel of the front wheels; and

wherein at least one of (i) said vision system displays images of a road in the forward direction of travel of the vehicle and the trailer and wherein said overlay indicates a steering path for the vehicle that tows the trailer around an obstacle and (ii) said vision system displays images of a road in the rearward direction of travel of the vehicle and the trailer and wherein said overlay indicates a steering path for the vehicle to drive the trailer into a selected location.

14. The vehicular vision system of claim 13 , wherein said vision system is operable to determine the trailer's width by side camera image evaluation.

15. The vehicular vision system of claim 13 , wherein said vision system is operable to at least one of (a) estimate the trailer's tendency to oscillate when driving forward and (b) estimate the trailer's tendency to oscillate when driving forward and cope with that oscillation.

16. The vehicular vision system of claim 13 , wherein trailer data is input into said vision system to provide data pertaining to physical characteristics of the trailer, and wherein said vision system is operable to determine the path of the trailer at least in part responsive to the trailer data.

17. The vehicular vision system of claim 16 , wherein said vision system is operable to store properties of a certain trailer in a data file that is reloaded when that certain trailer is connected at the vehicle and identified by said vision system, and wherein, responsive at least in part to image processing of captured image data, said vision system is operable to identify the trailer at the vehicle via identification of a trailer code element of the trailer that is viewable by said camera, and wherein said trailer code element comprises a target having a coded pattern established thereon.

18. A vehicular vision system, said vehicular vision system comprising:

a camera disposed at a vehicle and having an exterior field of view rearward of the vehicle, wherein said camera is operable to capture image data;

an image processor operable to process captured image data;

wherein, when the vehicle is towing a trailer, and based at least in part on image processing of image data captured by said camera during maneuvering of the vehicle and the trailer, said image processor (i) estimates a distance between a hitching point of the trailer and an axle of the trailer, and (ii) estimates a length of the trailer that includes the estimated distance between the hitching point of the trailer and the axle of the trailer and an estimated distance between the axle of the trailer and a rear end portion of the trailer;

wherein image data captured by said camera during maneuvering of the vehicle and the trailer includes image data captured by said camera when the vehicle is maneuvered with the trailer at an angle relative to the vehicle;

wherein said vision system, responsive at least in part to image processing of captured image data, is operable to determine a trailer angle of the trailer that is towed by the vehicle;

wherein said vision system is operable to determine a path of the trailer responsive to a steering angle of the vehicle and the determined trailer angle of the trailer and the estimated length of the trailer, and wherein said vision system is operable to display information for viewing by a driver of the vehicle to assist the driver in driving the vehicle with the trailer;

wherein, responsive at least in part to image processing of captured image data, said vision system is operable to identify the trailer at the vehicle via identification of a trailer code element of the trailer that is viewable by said camera;

wherein trailer data is input into said vision system to provide data pertaining to physical characteristics of multiple trailers and wherein trailer data for a particular trailer is accessed when that particular trailer is connected at the vehicle and identified by said vision system; and

wherein said vision system is operable to determine the path of the trailer at least in part responsive to the trailer data for the identified trailer.

19. The vehicular vision system of claim 18 , wherein said vision system is operable to display images of a road in the direction of travel of the vehicle and the trailer, and wherein said vision system is operable to display an overlay to indicate to the driver of the vehicle a steering path for the vehicle, and wherein said overlay comprises markers that indicate a determined path of travel of the front wheels of the vehicle and a path of travel that the wheels of the trailer will follow if the driver of the vehicle steers the front wheels of the vehicle along the determined path of travel of the front wheels.

20. The vehicular vision system of claim 18 , wherein said trailer code element comprises a target having a coded pattern established thereon.