Julie Beugin

• Dr.-Ing
• Researcher at Gustave Eiffel University

As the railway domain progresses towards autonomy, maintaining safety at levels comparable to human-operated systems is a crucial challenge. Autonomous trains require advanced systems capable of real-time risk assessment and decision-making, a task traditionally managed by human situational awareness. This paper introduces a novel risk-based decisi...

The level of automation in transportation systems is steadily on the rise, particularly in railways. However, this increase in automation implies a review of the previously established safety assessments, safety cases, and safety principles. Concretely, to ensure the overall safety of automated systems, it is crucial to provide conclusive assurance...

Moving Block is a railway signaling concept that paves the way for increasing line capacity while reducing maintenance and operating costs. Its implementation relies on autonomous solutions for train localization, mainly based on GNSS technology. However, the introduction of such technological innovations leads to the emergence of new risks. These...

The present document constitutes the D2.3 - Moving Block Verification and Validation (D2.3), which is part of WP2 - Modelling and Analysis of Moving Block Specifications (WP2) of the project PERformance-based Formal modelling and Optimal tRaffic Management for movINGblock RAILway signalling (PERFORMINGRAIL). D2.3 elaborates on the formal modelling...

In the railway field, rigorous development processes contribute to implement safe and efficient systems. Railway safety standards recommend the use of formal modelling and verification techniques to guarantee processes' correctness and validate safety requirements. In this paper, we present a methodology framework using formal models to verify movi...

The development of fully autonomous vehicles is an ambition that took seed in the automotive industry a few years ago and is now growing in the railways considering their benefits. The main objective of autonomous train is to perform its operations and assure its mission with an acceptable safety level in all possible operational conditions. Such a...

Absract The development of autonomous transportation has emerged as a great opportunity and big challenge for both researchers and manufacturers. When it comes to the autonomous train, the foremost objective is to maintain and assure the same level of safety as conventional trains. In case of the conventional trains, the driver has to stay aware of...

Within modern railways, Moving Block (MB) signalling systems represent the most efficient approach to ensure train separation. MB is a central concept in ERTMS/ETCS L3 (European Railway Traffic Management System / European Train Control System Level 3), which is an European standard for interoperable railways. Compared to traditional fixed block si...

The present document constitutes the Deliverable D2.2 “Moving Block Specification Development”, which is part of Work Package 2 of the “PERformance-based Formal modelling and Optimal tRaffic Management for movING-block RAILway signaling” project (PERFORMINGRAIL). This deliverable provides both semiformal specification and formal modelling of Moving...

Within modern railways, Moving Block (MB) signalling systems represent the most efficient approach to ensure train separation. MB is a central concept in ERTMS/ETCS L3 (European Railway Traffic Management System / European Train Control System Level 3), which is an European standard for interoperable railways. Compared to traditional fixed block si...

L’introduction du concept d’autonomie dans le secteur ferroviaire pose de nombreux défis, notamment en terme de sécurité. En effet, la gestion des aspects sécuritaires liés à l’utilisation des systèmes d’Intelligence Artificielle (IA), et de manière générale, à l’utilisation des différents sous-systèmes d’un train autonome sont deux verrous scienti...

The present document constitutes the Deliverable D2.1 “Modelling guidelines and Moving Block (MB) Use Cases characterization”, which is part of Work Package 2 of the “PERformance-based Formal modelling and Optimal tRaffic Management for movING-block RAILway signaling” project (acronym: PERFORMINGRAIL). This deliverable describes the selection metho...

In this paper, we extend the concept of the Operational Design Domain (ODD) to the context of railway remote driving in order to guide the safety demonstration process. Mainly, we propose an iterative process to define and to specify an ODD for the railway remote driving based on the operational risk assessment process. The main idea consists in, s...

The PERFORMINGRAIL project implements a holistic system approach to address the open challenges for the moving block concepts in terms of safe operational principles and specifications, reliable train integrity monitoring technologies, high-accuracy train positioning, and optimised moving block traffic management algorithms. In the frame of the PER...

In France, the railway lines are divided into the national and international lines. While the former has a proper implementation of the railway signalling systems as relay-based or computer-based systems, the latter follows the guidelines defined by the ERTMS standards, focusing on the interoperability throughout Europe. In a previous work we prese...

Several European actors of railways and GNSS (Global Navigation Satellite System) are committed to develop a safe on-board train positioning system including satellite localization technologies to enable the ETCS (European Train Control System) to manage rail traffic more efficiently. Known risky situations can arise when operating this system, esp...

In this paper, we discuss the general context and the methodology established to perform the operational safety demonstration of freight train remote driving. In addition, we briefly present the obtained results supported by a critical discussion of the methodology.

According to the evolution tendency of the control decision process from a trackside to a train-borne system, various autonomous localization units for railway vehicles were developed. As recommended in railway standards, the design process of each system, here the autonomous localization units (LU), follows the V-model whose first step is to defin...

Résumé Cet article rappelle les fondements de la démarche démontrant la sécurité (origines, et motivation des critères) dans les différents domaines sélectionnés pour cette étude: Spatial, Aéronautique, Automobile, Ferroviaire. A la fin de chaque partie, les auteurs ont proposé leurs conclusions pour de nouveaux domaines ou des missions multi-domai...

GNSS is expected to help the railway system to be modernized. However, such localization applications requires a high level of accuracy and safety that deserve to use the best potential of satellite-based technologies. The augmentation systems, as the satellite-based augmentation system EGNOS (European Geostationary Navigation Overlay Service), hel...

The use of Global Navigation Satellite Systems (GNSS) will provide significant advantages for ensuring the control of train movements on railway networks equipped with ERTMS/ETCS. Indeed, this disruptive technology can play an important role for reducing the rail infrastructure’s equipment by enabling trains to determine their position in an autono...

The work in the article presents the development of an application guide based on feedback and comments stemming from various railway actors on their practices of SIL allocation to railway safety-related functions. The initial generic methodology for SIL allocation has been updated to be applied to railway rolling stock safety-related functions in...

Railways have already introduced satellite-based localization systems for non-safety related applications. Driven by economic reasons, the use of these systems for new services and, in particular, their introduction in signaling system is seriously investigated today and tested all around the world. Because of the weight of their history, their str...

The objective of STARS task 5.1 is to review the existing navigation augmentation systems and services in terms of performances achieved and application environments, and to analyse the experimentations and projects already performed in railway applications related to the use of these systems and services. This report aims to draw the state of the...

Wireless communication links tend to be employed more and more in safety-critical railway applications. Their safe use in an advanced train control system (TCS) is an issue that is addressed in this paper by characterizing the TCS service interruption due to communication errors. More precisely, occurrence probabilities of single errors are first d...

Global Navigation Satellite Systems (GNSS) such as GPS, already used in aeronautics for safety-related applications, can play a major role in railway safety by allowing a train to locate itself safely. However, in order to implement this positioning solution in any embedded system, its performances must be evaluated according to railway standards....

This article presents a generic methodology for SIL allocation to railway rolling stock safety-related func-tions to solve the SIL concept application issues. This methodology is based on the flowchart formalism al-ready used in CSM European regulation. It starts with the use of quantitative safety requirements, particu-larly the Tolerable Hazard R...

The integrity concept, safety quality criterion for satellite-based localisation systems used in aeronautics, is described in terms of levels (protection and alert levels), time (Time To Alarm) and probability (integrity risk). In land transport applications, the requirements in terms of integrity differ from aeronautics in their definition and val...

The Communication Based Train Control (CBTC) systems today has generated immense interest in transport domain because of its ability to enhance safety and improve operational effectiveness. The current communication solutions for urban guided transport system that is based on the Wireless local area network (WLAN) becomes obsolete with a number of...

This article identifies and formalizes specific rules implicitly used for SIL allocation in TCMS (Train Control and Monitoring Systems). Firstly, the context of the SIL (Safety Integrity Level) used within the harmonized risk management process for railway systems in the European Union is presented. Then, the SIL allocation rules in different domai...

Ce livrable (L3) décrit l’allocation de SIL par les trois méthodes les plus significatives identifiées dans le livrable 2 pour deux exemples de systèmes génériques (portes d’accès voyageurs et frein d’urgence). Dans un premier temps, ces trois méthodes et leur mise en pratique sont présentées brièvement. Ensuite, les deux cas concrets sont décrits...

Global Navigation Satellite Systems (GNSS) is usually used in non-safety-related applications for various transportation modes. In order to employ GNSS (Global Navigation Satellite Systems) for train control application, numerous projects study if performance of GNSS can satisfy the railway safety requirements. In the railway context, multiple obst...

For railway positioning solutions based on GNSS (Global Navigation Satellite Systems) like the GPS (Global Positioning System) or the future Galileo, a generic model is impossible to create in regards to the signal degradations in the atmosphere, the multipath effects caused by receiver near-environment, the multitude of environment configurations...

This paper proposes to use sensibility measures to analyse the dependability and safety of railway localisation systems based on GNSS. In such systems, train positions are determined by combining all available sources of localisation information. However, each source of data suffers from specific errors, which are inherent to the nature of the sens...

Today, GNSS-based solutions (Global Navigation Satellite Systems) facilitate the implementation of the train localisation function on-board the vehicle. In the railway context, as a train has to travel different zones on its itinerary, multiple obstacles in these environments can cause different signal perturbations: multipaths, signal delays and m...

This paper aims at presenting the research work of formalisation of dependability-related localisation attributes within the framework of the European project QualiSaR. Processing of natural language is used with the aim of creating a structure of dependability and safety-related terms for evaluating automated systems in general and satellite posit...

Cet article se penche sur l’évaluation de propriétés de sûreté de fonctionnement de systèmes embarqués ferroviaires capables de se localiser à l’aide de signaux satellitaires. Plusieurs projets de recherche ont déjà montré l’intérêt et la faisabilité d’utiliser les GNSS (Global Navigation Satellite Systems) dans des applications ferroviaires. Pour...

Satellite-based localization technologies are strategic opportunities in railway applications because they offer new possibilities of service and have advantages that current technologies relying mainly on infrastructures deployed along tracks cannot equal. GNSSs (Global Navigation Satellite Systems) can, in particular, offer localization services...

Most of the positioning functions in railways today rely on track side sensors that are efficient, but offer mainly discrete positioning, lead to high maintenance costs and differ between countries. Railways demonstrate their interest for the localization technology based on GNSS. Use of the satellite technology for safety operations is a major pos...

Purpose GNSS is penetrating, surely but certainly, the railway market. Introduction is performed through non safety oriented applications such as fleet management or passenger information. However, a huge panel of safety applications could take advantage of this technology. Galileo will soon complement the navigation satellite offer, monopolized to...

Les techniques de localisation par satellites ont aujourd'hui montré leur intérêt dans diverses applications de transport terrestre. Le rôle du GNSS dans le service de positionnement est déterminé par les performances que le GNSS peut fournir aux utilisateurs. Les performances actuellement délivrées ne permettent pas d'utiliser l'information de pos...

The Safety-of-Life (SoL) Service - Level A of the satellite navigation system Galileo has great application potential for both aviation and railway safety- related systems with view to reduce operational, investment and maintenance cost. In aviation sector, radio navigation has been widely used for safety applications for several decades. Thats why...

Cet article pose les bases de l'etude de surete de fonctionnement (SdF) du service de localisation par satellites des trains. Pour cela sont prealablement detaillees les entraves pouvant porter atteinte au bon fonctionnement des systemes assurant la localisation, les GNSS (Global Navigation Satellite System). Pour assurer autant que possible les ex...

The Galileo Safety of Life (SoL) - Level A service has been designed mainly to support aeronautical operations ranging from en-route up to approach with vertical guidance (APV II). This is why the Galileo SoL Service has been specified by means of quality criteria coming from ICAO‘s (International Civil Aviation Organization) Required Navigation Pe...

Supervising trains on railway networks requires the knowledge of each train position. Today, positions are obtained by infrastructure-based equipments on the track. The use of a GNSS (Global Navigation Satellite System) like the GPS or the future Galileo System is considered as an interesting alternative to obtain position. It will allow activities...

Safety analysis in guided transportation systems is essential to avoid rare but potentially catastrophic accidents. This article presents a quantitative probabilistic model that integrates Safety Integrity Levels (SIL) for evaluating the safety of such systems. The standardized SIL indicator allows the safety requirements of each safety subsystem,...

A guided transportation system is a complex system, which integrates multiple interacting subsystems that ensure a safe transfer of passengers. Such safety means are distributed throughout the onboard and trackside subsystems, in order to avoid risky situations and potentially catastrophic accidents. The level of safety must be assessed to prove th...

La sûreté de fonctionnement comprend des approches qualitatives et quantitatives pour l'étude de systèmes complexes. Une des méthodes les plus utilisées est la méthode d'arbres de fautes. Celle-ci est basée sur la décomposition logique d'un événement redouté en événements élémentaires dont on connaît la probabilité d'occurrence. La probabilité de l...