Train Traffic Control System Safety Function Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current train traffic control systems face high costs due to the need for high safety integrity level components in command and status adapters for safety critical operations, which are expensive to develop, integrate, and test.

Innovation Solution

The function for controlling safety critical operations is separated from the command and status adapter and integrated into the route and train control system or a separate controller, allowing the command and status adapter to operate at a lower safety integrity level (SILO), reducing hardware and software development costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the command and status adapter is developed based on fail-safe computer systems with high Safety Integrity Level (SIL4), then safety requirements for controlling safety critical operations are fulfilled, but hardware costs and software development, integration and test costs are high

Engineering Contradiction:
Improvesafety integrity levelVSAvoiddevelopment and integration cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The system is divided into two functional parts: the command and status adapter operating at SIL0 level for basic communication functions, and the route and train control system operating at high SIL level for safety critical operations. This segmentation allows each component to be developed and certified at the appropriate safety level, reducing overall costs while maintaining safety requirements.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The safety critical functions are extracted from the command and status adapter and relocated to the route and train control system. This extraction allows the command and status adapter to operate at lower safety integrity level (SIL0), significantly reducing hardware and software development costs while the route and train control system maintains the required high safety level for safety critical operations.

Inventive Principle:
Principle #2Taking out (Extraction)

2Adaptability or versatility

If separate adapter modules are developed for each route and train control system, then specific protocol requirements are met, but the number of adapters and system complexity increase

Engineering Contradiction:
Improveprotocol compatibilityVSAvoidnumber of adapters
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The command and status adapter is designed as a universal multi-functional component that can interface with multiple different route and train control systems through software configuration. The adapter handles protocol conversion and communication functions for various systems (interlocking systems, radio-block-centers, etc.) without requiring separate hardware adapters, thereby reducing system complexity while maintaining broad compatibility.

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

Data Source

PatentEP3549841B1Train traffic control system and method for carrying out safety critical operations within a train traffic control system
Publication Date: 2022.06.01 THALES MANAGEMENT & SERVICES DEUTSCHLAND GMBH
  • EP3549841B1 patent drawingFigure 1
  • EP3549841B1 patent drawingFigure 2a~2b
  • EP3549841B1 patent drawingFigure 3a~3b

AI summary

A train traffic control system comprising a traffic management system (TMS) for executing safety critical operations, a route and train control system (RTCS), and a command and status adapter (COST), wherein the train traffic control system is adapted to exchange information and commands between the traffic management system (TMS) and the route and train control system (RTCS), wherein the command and status adapter (COST) comprises software components for carrying out functions with basic integrity, wherein the traffic control system further comprises a software component for carrying out a function for controlling safety critical operations, is characterized in that the function for controlling safety critical operations is outsourced from the command and status adapter (COST). The inventive train traffic control system on the one hand realizes a high safety level and on the other hand allows considerable cost reduction.