Vehicle Road Surface Recognition via Segmented 3D Modeling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing vehicle exterior environment recognition systems face challenges in accurately identifying road surfaces, particularly those distant from the vehicle, due to low reliability of images and parallax, which can lead to improper determination of road gradients or failure in extracting three-dimensional objects.

Innovation Solution

The system employs a vehicle exterior environment recognition apparatus with a first and second road surface identifier to generate road surface models by plotting representative distances of horizontal arrays of blocks, using pattern matching and stereo methods to derive parallax information, and applies the Hough transform to filter noise, ensuring accurate identification of road surfaces and three-dimensional objects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the system uses image-based road surface identification, then the road surface can be detected, but the reliability is low for distant road surfaces

Engineering Contradiction:
Improveroad surface identification reliabilityVSAvoiddistant road surface detection difficulty
Core Design Contradiction:
ReliabilityVSDifficulty of detecting and measuring

Solution Approach 1:

The patent divides the road surface detection task into multiple segments by creating multiple road surface models from different horizontal arrays of blocks at various vertical positions. Each model represents a specific depth range, allowing the system to systematically address distant road surface detection by processing it in manageable segments rather than as a single difficult task.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from two-dimensional image analysis to three-dimensional road surface modeling by plotting representative distances at respective vertical positions. This dimensional transformation enables the system to represent distant road surfaces in a 3D space, improving detection reliability by adding depth information and creating a more comprehensive spatial model.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Measurement precision

If the system plots representative distances of horizontal arrays of blocks, then road surface models are generated, but noise filtering is required

Engineering Contradiction:
Improvedistance measurement precisionVSAvoidnoise filtering complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces the Hough transform as an intermediary filtering mechanism between data collection and final road surface model generation. This intermediary process transforms the raw distance measurements into a standardized representation, automatically filtering noise while preserving accurate measurements, thus improving precision without proportionally increasing system complexity.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of information

If the system uses stereo methods to derive parallax information, then depth information is obtained, but image reliability is reduced for distant objects

Engineering Contradiction:
Improveparallax information accuracyVSAvoiddistant image reliability
Core Design Contradiction:
Loss of informationVSReliability

Solution Approach 1:

The patent applies preliminary filtering and processing to the parallax information before final road surface model generation. By pre-processing the distance measurements and applying the Hough transform to filter noise early in the pipeline, the system preserves accurate parallax information while compensating for the reduced reliability of distant images through systematic error reduction.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentUS10803605B2Vehicle exterior environment recognition apparatus
Publication Date: 2020.10.13 SUBARU CORP
  • US10803605B2 patent drawing
  • US10803605B2 patent drawing
  • US10803605B2 patent drawing

AI summary

A vehicle exterior environment recognition apparatus includes a first road surface identifier and a second road surface identifier. The first road surface identifier identifies a first road surface region of a road surface in an image and generates a first road surface model by plotting, at respective vertical positions, representative distances of horizontal arrays of blocks in the first road surface region. The second road surface identifier identifies a second road surface region in the image and generates a second road surface model by plotting, at respective vertical positions, representative distances of horizontal arrays of blocks in the second road surface region. The second road surface region is a region of the road surface that is farther from a vehicle than the first road surface region is, and has a horizontal length greater than a horizontal length of the first road surface region in a three-dimensional space.