Lane Line Estimation Using Width Constraints and Dispersion Analysis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing lane line estimating apparatuses struggle to accurately detect lane lines on express highways, particularly double white lines and tracks that can be erroneously recognized due to brightness differences and reflection light from puddles, leading to poor detection precision and unstable driving control.

Innovation Solution

A lane line estimating apparatus that includes an imaging unit, a storage unit for lane-line width data, a lane-line candidate point setting unit, a curve approximation processing unit, and a lane-line type estimating unit, which detects lane-line detection points, sets candidate points based on lane-line width, and uses curve approximation to estimate lane-line types by analyzing dispersion, thereby accurately identifying true lane lines even in complex scenarios.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If edge detection based on brightness difference is used to detect lane lines, then detection speed is improved, but measurement precision deteriorates due to erroneous recognition of double white lines and tracks as lane lines

Engineering Contradiction:
Improvedetection speedVSAvoidlane line detection precision
Core Design Contradiction:
SpeedVSMeasurement precision

Solution Approach 1:

The patent segments the lane line detection process into multiple stages: initial edge detection, candidate point identification, and verification through geometric relationships. By dividing the detection process, the system maintains fast initial detection while adding precision through subsequent verification steps that distinguish true lane lines from false targets like double white lines and tracks.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent implements feedback mechanisms where detected candidate points are verified against expected geometric relationships and patterns. The system uses feedback from multiple detection passes and consistency checks to confirm whether detected edges represent actual lane lines, thereby improving measurement precision while maintaining detection speed through intelligent filtering.

Inventive Principle:
Principle #23Feedback

2Device complexity

If simple edge detection is used, then device complexity is reduced, but measurement precision deteriorates due to inability to distinguish true lane lines from pseudo lines

Engineering Contradiction:
Improvedetection algorithm complexityVSAvoidlane line detection precision
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent applies preliminary actions by first detecting candidate edge points, then systematically verifying each candidate against geometric constraints and patterns before finalizing lane line identification. This preliminary verification process adds precision without requiring complex hardware, using computational checks to filter false positives while maintaining relatively simple device architecture.

Inventive Principle:
Principle #10Preliminary action

3Ease of operation

If lane line detection is performed without considering lane-line width variations, then ease of operation is improved, but measurement precision deteriorates due to inability to identify correct lane lines among multiple candidates

Engineering Contradiction:
Improvedetection process simplicityVSAvoidlane line position accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent applies local quality by considering lane-line width variations at different locations and orientations. The system adjusts detection parameters and verification criteria based on local characteristics of the road environment, allowing it to maintain ease of operation through automated adaptation while improving measurement precision through location-specific optimization of detection sensitivity and geometric verification.

Inventive Principle:
Principle #3Local quality

Data Source

PatentUS8611609B2Lane line estimating apparatus
Publication Date: 2013.12.17 SUBARU CORP
  • US8611609B2 patent drawing
  • US8611609B2 patent drawing
  • US8611609B2 patent drawing

AI summary

A fixed data memory stores data of a normal lane width between lane lines and a narrow lane width between inner guide lines of double white lines. A lane-line candidate setting section detects lane-line detection points on both sides of a driving lane using a captured image, and sets lane-line candidate points on the opposite lane lines at spaces of the widths and therebetween, using the detection points as starting points. A curve approximation processing section sets virtual lines on both sides of the driving lane from a curve approximation equation obtained using the detection and candidate points. A lane-line position setting section obtains dispersions of the candidate points to the left and right virtual lines, and estimates the type of at least one of the left and right virtual lines.