Lane-Level Navigation Rematching at Route Branch Points

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Navigation devices struggle to quickly re-match the position of a vehicle on a map when it deviates from a designated guidance route to an alternate route, especially at branch points, leading to uncertainty and potential disruption of automatic driving.

Innovation Solution

The system integrates a navigation device with a high-definition map and a determining unit to compare vehicle positions on both standard-definition and high-definition maps, adjusting matching reliability with added values to ensure accurate re-matching on the correct route, allowing for quick re-route setting and continuous automatic driving.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If the navigation device uses standard route matching methods, then the system complexity remains low, but the position re-matching speed deteriorates when the vehicle deviates from the guidance route

Engineering Contradiction:
Improveposition re-matching speedVSAvoidsystem complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The system pre-calculates and stores multiple candidate routes including alternate routes before the vehicle reaches branch points. When deviation occurs, the pre-prepared candidate routes enable immediate re-matching without complex real-time calculations, thus improving re-matching speed while keeping system complexity manageable.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The route matching system dynamically adjusts between standard matching and alternate route matching based on vehicle position and route deviation detection. The system transitions from static standard matching to dynamic alternate route evaluation when deviation is detected, optimizing both speed and accuracy without requiring permanently complex structures.

Inventive Principle:
Principle #15Dynamics

2Speed

If the navigation device implements quick re-matching algorithms, then the position re-matching speed improves, but the reliability of route identification deteriorates due to potential misidentification at branch points

Engineering Contradiction:
Improveposition re-matching speedVSAvoidroute identification reliability
Core Design Contradiction:
SpeedVSReliability

Solution Approach 1:

The system implements feedback mechanisms where the detected vehicle position is continuously compared with expected positions on candidate routes. When misidentification is detected through position deviation feedback, the system automatically re-evaluates candidate routes and adjusts matching results, ensuring both speed and reliability in route identification.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system introduces an intermediary verification step that acts as a mediator between quick matching algorithms and final route identification. This intermediary layer validates candidate route selections by checking consistency with vehicle position, travel direction, and route characteristics, preventing misidentification while maintaining quick re-matching capability.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Measurement precision

If the navigation device uses high-definition maps with detailed route information, then the measurement precision of vehicle position improves, but the device complexity and data processing requirements worsen

Engineering Contradiction:
Improvevehicle position precisionVSAvoiddata processing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The high-definition map data is segmented into essential positional reference information and detailed route information. The system selectively processes only the essential positional reference data needed for quick re-matching, while storing detailed route information in a compressed or pre-processed format. This segmentation enables high measurement precision without requiring the system to process all detailed map data simultaneously.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3979224B1Navigation device, autonomous driving control device, and navigation method
Publication Date: 2025.09.24 NISSAN MOTOR CO LTD
  • EP3979224B1 patent drawingFigure 1
  • EP3979224B1 patent drawingFigure 2
  • EP3979224B1 patent drawingFigure 3

AI summary

A navigation device comprising: own vehicle position detecting means configured to detect position information of own vehicle; route setting means configured to set a guidance route that guides the own vehicle to a destination on the basis of a first map including information of a traveling route and the position information of the own vehicle; matching means configured to match a position of the own vehicle as a first own position with the traveling route where the own vehicle travels on the first map on the basis of the position information of the own vehicle; driving lane detecting means configured to match the position of the own vehicle as a second own position with a driving lane where the own vehicle travels on a second map on the basis of the second map including information of the driving lane in the traveling route and the position information of the own vehicle; and determining means configured to determine whether the second own position is included in the first own position, wherein when the guidance route is set, the matching means matches the first own position on the guidance route, and when the second own position is no longer included in the first own position thereafter, the matching means matches the first own position on the first map on the basis of the position information.