Trailer backup assist system with predictive hitch angle functionality

• US 10,710,585 B2
• Filed: 09/01/2017
• Issued: 07/14/2020
• Est. Priority Date: 09/01/2017
• 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, Recker, Darrel Alan, Joyce, John P., Mattern, Donald Jacob, Hafner, Michael, Xu, Li, Tseng, Eric Hongtei, Pilutti, Thomas Edward
• Primary Examiner(s): Bendidi, Rachid
• Application Number:
  US15/693,999
• Publication Number:
  US 20190071088A1
• Time in Patent Office: 1,047 Days
• CPC Class Codes: B60D 1/245 for facilitating push back or parking of trailers
• CPC Class Codes: B60D 1/62 involving supply lines, electric circuits, or the like
• CPC Class Codes: B60K 35/00 Instruments specially adapted for vehicles; Arrangement of instruments in or on vehicles
• CPC Class Codes: B60R 2300/307 virtually distinguishing relevant parts of a scene from the background of the scene
• CPC Class Codes: B60R 2300/80 characterised by the intended use of the viewing arrangement
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/20 including control of steering systems
• CPC Class Codes: B60W 2710/18 Braking system
• CPC Class Codes: B60W 2710/20 Steering systems
• CPC Class Codes: B60W 30/18036 Reversing
• CPC Class Codes: B62D 1/22 Alternative steering-control elements, e.g. for teaching purposes
• 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: G06T 11/60 Editing figures and text; Combining figures or text
• CPC Class Codes: G06T 2207/10016 Video; Image sequence
• CPC Class Codes: G06T 2207/30264 Parking
• CPC Class Codes: G06T 7/13 Edge detection
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes
• CPC Class Codes: G06T 7/73 using feature-based methods
• CPC Class Codes: G06T 7/74 involving reference images or patches
• CPC Class Codes: G06T 7/80 : Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration

Abstract

A trailer backup assist system is provided herein. The system includes a calibration feature for calibrating an imaging device used for hitch angle detection. The system also employs multiple hitch angle detection methods, a number of which may run in parallel to increase the intervals at which a hitch angle can be measured. The system additionally includes a predictive feature in which a hitch angle can be predicted in instances where a trailer sensing device fails. The system is further configured to estimate a trailer length and generate steering commands that are invariant to the estimated trailer length under certain conditions.

Claims

1. A method of determining an offset for calibrating an imaging device comprising the steps of:

using the imaging device to capture an image of a rear bumper; and

providing a controller configured to;

process the captured image;

identify a boundary separating the rear bumper from a ground based on the captured image;

compare the identified boundary to an ideal boundary;

determine an offset between the identified boundary and the ideal boundary, wherein the offset is defined by a vector having a horizontal component, a vertical component, and a rotational component, and the controller determines the offset by iterating on candidates for each of the horizontal, vertical, and rotational components until the identified boundary overlaps with the ideal boundary; and

calibrating the imaging device based on the determined offset.

2. The method of claim 1, wherein the ideal boundary comprises a continuous line.

3. The method of claim 1, wherein the ideal boundary comprises a line having a break.

4. The method of claim 1, wherein the ideal boundary is overlaid onto the captured image.

5. The method of claim 1, wherein the controller is further configured to generate a warning if the offset is unable to be determined.

6. A calibration method, comprising the steps of:

using an imaging device to capture an image of a rear bumper; and

providing a controller configured to;

process the captured image;

identify a boundary separating the rear bumper from a ground based on the captured image;

compare the identified boundary to an ideal boundary; and

calibrate the imaging device by determining an offset between the identified boundary and the ideal boundary, wherein the offset is defined by a vector having a horizontal component, a vertical component, and a rotational component, and the controller determines the offset by iterating on candidates for each of the horizontal, vertical, and rotational components until the identified boundary overlaps with the ideal boundary.