Geolocation Integrity Control via Landmark Measurement Validation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Geolocation methods using landmarks lack integrity control, leading to potential errors and noise accumulation, which can result in erroneous device positioning without detection.

Innovation Solution

An integrity control method and device that analyze measurements from landmarks to detect failures such as scalar and vector biases, using a calculation module to estimate a state vector and determine a test variable, triggering alerts when integrity is compromised.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If landmark-based geolocation methods are used, then geolocation capability is provided, but integrity control is lacking leading to undetected errors

Engineering Contradiction:
Improveintegrity controlVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system segments the geolocation functionality into two independent parts: the geolocation calculation module that determines position from landmark measurements, and the integrity control module that separately validates the measurements. This segmentation allows integrity monitoring to be added without fundamentally changing the core geolocation algorithm, resolving the contradiction between improving reliability and maintaining system simplicity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary integrity control module that acts as a mediator between the measurement collection process and the geolocation calculation. This module receives measurements, performs consistency checks using multiple validation techniques, and either approves or rejects measurements before they reach the geolocation engine, thereby improving reliability without requiring complete system redesign.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If multiple measurement sources are used for geolocation, then redundancy is provided, but error accumulation increases

Engineering Contradiction:
Improveposition accuracyVSAvoiderror accumulation
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The integrity control module implements feedback mechanisms that continuously monitor measurement consistency and provide corrective actions. When measurements from multiple sources show signs of error accumulation or inconsistency, the system adjusts by identifying and excluding problematic measurements, thereby maintaining position accuracy while utilizing the benefits of redundant measurement sources.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system performs preliminary validation checks on measurements before they are used in geolocation calculations. By pre-screening measurements for consistency, plausibility, and cross-validation against other sources, the system prevents erroneous measurements from entering the calculation process, thus avoiding error accumulation while maintaining the advantages of multiple measurement sources.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4214532B1Method for checking the integrity of calibration on a plurality of landmarks, associated computer program product and associated integrity checking device
Publication Date: 2024.06.19 THALES SA
  • EP4214532B1 patent drawingFigure 1
  • EP4214532B1 patent drawingFigure 2
  • EP4214532B1 patent drawingFigure 3

AI summary

This method comprises the steps of determining (120) an estimated state vector based on a measurement vector comprising landmark position measurements, landmark direction measurements and distance measurements; of determining (130) a test variable; of determining (140) a decentralization value for the distribution law of said variable, determining (150) a minimum detectable bias based on the decentralization value, on the test variable and on a feature vector associated with this type of failure; and of determining (160) a protective radius based on the or each minimum detectable bias.