Train Integrity Verification Using Odometry Confidence Intervals

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for verifying train integrity are costly due to the need for special track adaptations and unreliable length measurements using track circuits, which do not meet safety standards.

Innovation Solution

A system and method on board the train using communication and synchronization means, odometry with confidence intervals, and detection circuits to calculate the train's length, ensuring integrity verification at reduced costs while meeting safety standards by expressing distance traveled as a confidence interval and validating measurements based on predetermined lengths.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If special devices are installed along the tracks to count axles, then train integrity verification is achieved, but the cost increases due to special track adaptation

Engineering Contradiction:
Improvetrain integrity verificationVSAvoidtrack adaptation
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The train itself performs the integrity verification using its own on-board odometry means, eliminating the need for external specialized tracking devices. The train's odometer measures its own length by recording position at the entry and exit of a standard track circuit, making the system self-sufficient and removing complex track adaptations.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

Instead of using specialized physical counting devices on the track, the system uses the train's existing odometry information (a copy of position data) to verify integrity. The odometric references recorded by the train's own equipment serve as a substitute for external axle counting devices.

Inventive Principle:
Principle #26Copying

2Device complexity

If track circuits are used to measure train length, then cost is reduced, but measurement reliability is insufficient to meet safety standards

Engineering Contradiction:
Improvetrack circuit usageVSAvoidlength measurement
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The system uses feedback from the train's odometry means to validate and refine the length measurement. By comparing the odometric distance (difference between exit and entry references) with the known train length from the database, the system ensures measurement reliability meets safety standards while using simple track circuits.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The train's odometry means continuously records position information before the integrity verification is needed. The odometric references at entry and exit points are already available when the train passes through the track circuit, eliminating the need for complex real-time measurement systems and ensuring reliability through pre-captured data.

Inventive Principle:
Principle #10Preliminary action

3Device complexity

If odometry means with relative uncertainty are used, then equipment cost is reduced, but measurement precision is affected

Engineering Contradiction:
Improveodometry meansVSAvoiddistance traveled
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The system measures more than needed by recording odometric references at both entry and exit points of the track circuit, creating a confidence interval rather than a single value. This excessive measurement approach (measuring minimum and maximum distances) compensates for the odometry means' relative uncertainty and ensures measurement precision meets safety standards.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP1832493B1System and method of verifying the integrity of a train
Publication Date: 2008.12.31 ALSTOM BELGIUM SA
  • EP1832493B1 patent drawingFigure 1~3
  • EP1832493B1 patent drawingFigure 4~5
  • EP1832493B1 patent drawingFigure 6

AI summary

The system has a communication unit (7) communicating with a detection unit (4) of a short railway circuit (3). The unit (4) detects presence/absence of the train on the circuit (3). A calculation unit (9) calculates the distance traveled by the train between an instant in which the train holds the circuit (3) and an instant in which the train releases the circuit (3). The distance is expressed in the form of a confidence interval so that the probability that the train has not traveled a distance included in the interval is lower than probability compatible with standard railway safety. An independent claim is also included for a method of verifying an integrity of a train of a determined length.