Image-Based Trailer Hitch Angle Estimation Without Mounted Targets

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing trailer tracking systems require a target to be mounted on the trailer, which can be time-consuming to set up and may not be feasible depending on the trailer configuration, leading to inaccuracies in tracking the hitch angle.

Innovation Solution

A control system that uses image data from a vehicle-mounted sensor to calculate the hitch angle without a target on the trailer, by determining offset and correction angles, allowing for accurate and robust tracking of the trailer's movement, and mitigating errors through differential processing and calibration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a target is mounted on the trailer to enable tracking, then the trailer can be tracked by the image sensor, but the setup becomes time-consuming and may not be feasible depending on trailer configuration

Engineering Contradiction:
Improvetrailer tracking accuracyVSAvoidsetup time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The invention extracts the target requirement from the system by using the trailer's own features (lights, reflections, geometric shapes) as tracking markers instead of requiring an external mounted target. This eliminates the need for physical target installation while maintaining tracking capability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The trailer serves itself as the tracking target by utilizing its inherent features such as lights, reflective surfaces, and geometric structures. The system processes the trailer's own visual characteristics to establish tracking parameters without external assistance or additional components.

Inventive Principle:
Principle #25Self-service

2Measurement precision

If a target is mounted on the trailer in a specified location, then consistent tracking can be achieved, but this may not be possible depending on the configuration of the trailer

Engineering Contradiction:
Improvehitch angle measurement accuracyVSAvoidcompatibility with different trailer configurations
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The system achieves universal compatibility across different trailer configurations by using multiple potential tracking features (lights, reflections, geometric shapes) that can be found on various trailer types. The algorithm can select from multiple feature types depending on what is available on the specific trailer being tracked.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system changes the tracking parameters dynamically by selecting different visual features (lights vs. reflections vs. geometric shapes) based on the trailer's configuration, lighting conditions, and viewing angle. This allows the same system to adapt to various trailer types without requiring physical modification.

Inventive Principle:
Principle #35Parameter changes

3Extent of automation

If image processing techniques are used to determine hitch angle, then tracking can be achieved, but inaccuracies may be introduced that affect subsequent frames

Engineering Contradiction:
Improveautomated trailer trackingVSAvoidhitch angle accuracy
Core Design Contradiction:
Extent of automationVSMeasurement precision

Solution Approach 1:

The system uses feedback mechanisms where the determined hitch angle and trailer position are continuously monitored and used to adjust subsequent image processing parameters. Error correction is applied by comparing expected vs. actual positions and refining the tracking algorithm accordingly to prevent error propagation.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system performs preliminary calibration and establishes baseline tracking parameters before正式开始 tracking. Reference images and initial hitch angle calculations are prepared in advance to provide accurate starting points for subsequent real-time tracking, reducing the need for complex real-time corrections.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3972857B1Vehicle control system and method
Publication Date: 2024.07.10 JAGUAR LAND ROVER LTD
  • EP3972857B1 patent drawingFigure 1
  • EP3972857B1 patent drawingFigure 2
  • EP3972857B1 patent drawingFigure 3

AI summary

Aspects of the present invention relate to a control system (2) for monitoring a movement of a trailer (3) connected to a vehicle (1). The control system comprises one or more controllers (5) and is configured to: receive image data from an image sensor (10) disposed on the vehicle; store image data corresponding to a central reference image, a current reference image and a current frame and associate an offset angle with the current reference image, and associate a correction angle with current reference image. The control system (2) is configured to compare the current reference image to the current frame to determine a change angle; determine a hitch angle in dependence on the offset angle, the change angle and the correction angle; and output the hitch angle.