Hitch assist system with hitch coupler identification feature and hitch coupler height estimation

• US 10,363,874 B2
• Filed: 09/19/2017
• Issued: 07/30/2019
• Est. Priority Date: 09/19/2017
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Zhang, Yi, Tseng, Eric Hongtei, Lakehal-ayat, Mohsen, Pilutti, Thomas Edward
• Primary Examiner(s): Entezari, Michelle M
• Application Number:
  US15/708,427
• Publication Number:
  US 20190084479A1
• Time in Patent Office: 679 Days
• Field of Search: None
• CPC Class Codes: B60D 1/06 Ball-and-socket hitches , e.g. constructional details, auxiliary devices, their arrangement on the vehicle
• CPC Class Codes: B60D 1/36 for facilitating connection, e.g. hitch catchers , visual guide means, signalling aids B60D1/465 takes precedence; vehicle signalling in general B60Q; optical arrangements specially adapted for viewing trailer-hitches B60R1/003
• CPC Class Codes: B60R 1/00 Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
• CPC Class Codes: B60R 1/003 for viewing trailer hitches
• CPC Class Codes: B60R 1/26 to the rear of the vehicle
• CPC Class Codes: B60R 2300/20 characterised by the type of display used
• CPC Class Codes: B60R 2300/307 virtually distinguishing relevant parts of a scene from the background of the scene
• CPC Class Codes: B60R 2300/808 for facilitating docking to a trailer
• CPC Class Codes: B62D 15/028 Guided parking by providing commands to the driver, e.g. acoustically or optically
• CPC Class Codes: B62D 15/0285 Parking performed automatically
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2207/20101 Interactive definition of point of interest, landmark or seed
• CPC Class Codes: G06T 2207/30252 Vehicle exterior; Vicinity of vehicle
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06T 7/13 Edge detection
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes

Abstract

A hitch assist system and method are provided herein. An imager captures one or more images of a trailer having a hitch coupler. A user-input device is provided for specifying a location of the hitch coupler in the one or more captured images. A controller generates an image patch around the user-specified location, segments the image patch to identify the hitch coupler, and estimates a trailer height based on a height and projective geometry of the imager.

Claims

1. A hitch assist system comprising:

an imager for capturing one or more images of a trailer having a hitch coupler;

a user-input device for specifying a location of the hitch coupler in the one or more captured images; and

a controller for;

generating an image patch around the user-specified location;

segmenting the image patch to identify the hitch coupler; and

estimating a trailer height based on both a height and projective geometry of the imager, wherein the projective geometry comprises at least two angles between a first plurality of field of view components and the ground and at least two angles between a second plurality of field of view components and a longitudinal axis of the trailer, and wherein the first and second plurality of field of view components originate from the imager and are selected based on a projective geometry of the imager.

2. The hitch assist system of claim 1, wherein the user-input device comprises a touchscreen display of a vehicle.

3. The hitch assist system of claim 2, wherein the touchscreen display registers one or more touch events thereon for specifying the location of the hitch coupler.

4. The hitch assist system of claim 1, wherein the imager is located on a rear of a vehicle and is disposed to capture one or more images of a rear-vehicle scene.

5. The hitch assist system of claim 1, wherein segmenting the image patch locates a boundary of the hitch coupler.

6. The hitch assist system of claim 1, wherein the trailer height comprises a height of the hitch coupler relative to the ground.

7. The hitch assist system of claim 1, wherein the hitch coupler comprises a coupler ball socket.

8. The hitch assist system of claim 1, wherein the controller further determines a horizontal distance between the imager and the hitch coupler based on the estimated trailer height, the height of the imager, a focal length of the imager, a pitch of the imager, and a distance between the imager and a tow hitch of a vehicle.

9. The hitch assist system of claim 1, wherein the controller estimates the trailer height by simultaneously solving a system of two equations.

10. A hitch assist method comprising the steps of:

capturing one or more images of a trailer having a hitch coupler;

specifying a location of the hitch coupler in the one or more captured images;

generating an image patch around the user-specified location;

segmenting the image patch to identify the hitch coupler; and

estimating a trailer height based on both a height and projective geometry of the imager, wherein the projective geometry comprises at least two angles between a first plurality of field of view components and the ground and at least two angles between a second plurality of field of view components and a longitudinal axis of the trailer, and wherein the first and second plurality of field of view components originate from the imager and are selected based on a projective geometry of the imager.

11. The hitch assist method of claim 10, wherein the step of specifying is performed using a touchscreen display of a vehicle.

12. The hitch assist method of claim 11, wherein the touchscreen display registers one or more touch events thereon for specifying the location of the hitch coupler.

13. The hitch assist method of claim 10, wherein the one or more images comprise a rear-vehicle scene.

14. The hitch assist method of claim 10, wherein the step of segmenting the image patch comprises locating a boundary of the hitch coupler.

15. The hitch assist method of claim 10, wherein the trailer height comprises a height of the hitch coupler relative to the ground, and wherein the hitch coupler comprises a coupler ball socket.

16. The hitch assist method of claim 10, further comprising the step of determining a horizontal distance between the imager and the hitch coupler based on the estimated trailer height, the height of the imager, a focal length of the imager, a pitch of the imager, and a distance between the imager and a tow hitch of a vehicle.

17. The hitch assist method of claim 10, wherein the step of estimating a trailer height comprises simultaneously solving a system of two equations.

18. A hitch assist system comprising:

an imager for capturing one or more images of a trailer having a hitch coupler;

a user-input device for specifying a location of the hitch coupler in the one or more captured images; and

a controller for;

generating an image patch around the user-specified location;

segmenting the image patch to identify the hitch coupler; and

estimating a height difference between the imager and the hitch coupler based on both a height and projective geometry of the imager, wherein the projective geometry comprises at least two angles between a first plurality of field of view components and the ground and at least two angles between a second plurality of field of view components and a longitudinal axis of the trailer, and wherein the first and second plurality of field of view components originate from the imager and are selected based on a projective geometry of the imager.