DRAWBAR SCAN SOLUTION FOR LOCATING TRAILER HITCH POINT

• US 20170178328A1
• Filed: 12/17/2015
• Published: 06/22/2017
• Est. Priority Date: 12/17/2015
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Hu, Zheng, Joyce, John P.
• Granted Patent: US 9,934,572 B2
• Time in Patent Office: Days
• CPC Class Codes: G06T 7/12 Edge-based segmentation
• CPC Class Codes: G06T 7/13 Edge detection
• CPC Class Codes: G06T 7/33 using feature-based methods
• CPC Class Codes: G06T 7/73 using feature-based methods
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

A system for locating an imaged hitch point between a vehicle and a trailer is provided herein. An imaging device is configured to capture images of the trailer. A controller is configured to select two images captured by the imaging device and derive an edge map for each of the two images. The controller determines the location of the imaged hitch point based on differences in pixel intensity associated with a number of predefined pixel positions common to the two images.

Claims

1. A system for locating an imaged hitch point between a vehicle and a trailer, comprising:

an imaging device configured to capture images of the trailer

a controller configured to;

select two images captured by the imaging device;

derive an edge map for each of the two images; and

determine the location of the imaged hitch point based on differences in pixel intensity associated with a number of predefined pixel positions common to the two images.

2. The system of claim 1, wherein the two images selected by the controller each show the trailer at a distinct hitch angle with regards to the vehicle.

3. The system of claim 1, wherein the two images are successive or non-successive.

4. The system of claim 1, wherein the edge map for each of the two images is derived by calculating an edge value for each of their corresponding pixels.

5. The system of claim 1, wherein the number of pixel positions are spaced along a rderence line that extends vertically across a middle column of each of the two images.

6. The system of claim 5, wherein the reference line coincides with a longitudinal axis of an imaged drawbar.

7. The system of claim 1, wherein the controller selects, as the imaged hitch point, a pixel position that is common to the two images and is associated with a difference in pixel intensity that meets or exceeds a predetermined threshold value.

8. A method of locating an imaged hitch point between a vehicle and a trailer, comprising the steps of:

capturing images of the trailer using an imaging device;

providing a. controller configured to;

select two images captured by the imaging device;

derive an edge map for each of the two images; and

determine the location of the imaged hitch point based on differences in pixel intensity associated with a number of predefined pixel positions common to the two images.

9. The method of claim 8, wherein the two images selected by the controller each show the trailer at a distinct hitch angle with regards to the vehicle.

10. The method of claim 8, wherein the two images are successive or non-successive.

11. The method of claim 8, wherein the edge map for each of the two images is derived by calculating an edge value for each of their corresponding pixels.

12. The method of claim 8, wherein the number of pixel positions are spaced along a reference line that extends vertically across a middle column of each of the two images.

13. The method of claim 12, wherein the reference line coincides with a longitudinal axis of an imaged drawbar and intersects with the imaged hitch point.

14. The method of claim 8, wherein the controller selects, as the imaged hitch point, a pixel position that is common to the two images and is associated with a difference in pixel intensity that meets or exceeds a predetermined threshold value.

15. A method of locating an imaged hitch point between a vehicle and a trailer, comprising the steps of:

capturing images of the trailer using an imaging device;

providing a controller configured to;

a) select two images captured by the imaging device;

b) derive an edge map for each of the two images

c) define a detection window centered at a common pixel position in each of the two images;

d) calculate an average pixel intensity of the pixels bounded by each detection window;

e) calculate an averaged pixel difference defined as the absolute value of the difference between the average pixel intensities calculated at (d);

f) shift each detection window in a common direction such that the detection window in each of the two images is centered at a new common pixel position;

g) iterate (d)-(f) until the calculated averaged pixel difference meets or exceeds a threshold value; and

h) select, as the imaged hitch point, the common pixel position associated with the calculated averaged pixel difference that meets or exceeds the threshold value.

16. The method of claim 15, wherein the two images selected by the controller each show the trailer at a distinct hitch angle with regards to the vehicle.

17. The method of claim 16, wherein the two images are successive or non-successive.

18. The method of claim 15, wherein each detection window is shifted along a reference line that extends vertically across a middle column of the corresponding image.

19. The method of claim 18, wherein the reference line coincides with a longitudinal axis of an imaged drawbar and intersects with the imaged hitch point.