Monocular Road Unevenness Recognition for Night Speed Bump Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing speed bump detection methods using stereo camera disparity face accuracy issues due to distance limitations and noise, especially at night, making it difficult to detect uneven road portions with high precision.

Innovation Solution

An environment recognition device equipped with a monocular camera that utilizes image acquisition, traveling environment recognition, and uneven portion detection units to calculate the height of three-dimensional objects and detect road surface irregularities based on height changes, eliminating the need for disparity calculations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If stereo camera disparity method is used to detect speed bumps, then detection capability is provided, but measurement precision deteriorates at long distances and nighttime due to noise and blurring

Engineering Contradiction:
Improvespeed bump detection accuracyVSAvoidnoise and blurring at night
Core Design Contradiction:
Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The invention extracts and utilizes the shadow cast by the speed bump on the road surface as a separate detection feature, rather than relying on direct disparity measurement of the speed bump itself. This extracted shadow information provides detection capability that is less affected by distance and lighting conditions.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The shadow on the road surface acts as an intermediary indicator of the speed bump's presence. Instead of directly measuring the speed bump which suffers from disparity accuracy issues, the system detects the shadow which serves as a more reliable proxy, especially in nighttime conditions where the speed bump itself becomes difficult to detect.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If stereo camera system is used for speed bump detection, then three-dimensional detection capability is achieved, but device complexity and cost increase

Engineering Contradiction:
Improvethree-dimensional object detectionVSAvoidcamera system configuration
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The monocular camera is designed to perform multiple functions: capturing images of the road surface, identifying shadows, and inferring three-dimensional information about speed bumps. This multi-functionality eliminates the need for separate stereo camera systems while maintaining detection capability.

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

Solution Approach 2:

The invention replaces the mechanical/optical stereo system with a computational approach using a single camera. Instead of using two physical cameras to achieve depth perception, the system uses image processing algorithms to extract three-dimensional information from a single monocular image by analyzing shadow characteristics.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If disparity calculation is used for road surface analysis, then uneven portion detection is enabled, but reliability decreases when disparity accuracy is low

Engineering Contradiction:
Improveuneven portion detection reliabilityVSAvoiddisparity measurement accuracy
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The invention changes the detection parameter from direct disparity measurement to shadow characteristic analysis. By monitoring changes in shadow position, shape, and intensity rather than relying on disparity calculations, the system achieves more reliable detection of road surface unevenness especially when disparity accuracy deteriorates.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4703678A1Environment recognition device
Publication Date: 2026.03.04 ASTEMO LTD
  • EP4703678A1 patent drawingFigure 1~2
  • EP4703678A1 patent drawingFigure 3(1)~3(2)
  • EP4703678A1 patent drawingFigure 4(1)~4(2)

AI summary

An environment recognition device (1) mounted on a vehicle includes: an image acquisition unit (100) that acquires an image captured by a camera (2); a traveling environment recognition unit (101) that recognizes a three-dimensional object positioned at a boundary of a traveling path based on the image; and an uneven portion detection unit (102) that calculates a height of the three-dimensional object in a depth direction, and detects an uneven portion of a road surface of the traveling path based on a calculated height change.