Held every three years, the World Congress of Railway Research (WCRR) is the world’s largest international congress on railway research, gathering researchers, technical experts and industry leaders on innovation. At this edition Radiolabs has contributed to the selected theme on “Inspiring innovative and resilient railways” with three papers relevant to new R&D projects to showcasing the benefits of adopting satellite technologies for the evolution of the ERTMS/ETCS train control.
The RAN Project – Nation-wide Augmentation Network – funded by ASI, the Italian Space Agency – is developing a ground network to correct the GPS and GALILEO signals in order to improve the performance and safety of GNSS-based positioning systems. With a novel multi-layer architecture reusing existing infrastructures as EGNOS designed for aviation, GALILEO HAS- High Accuracy Services and Local networks – the proposed architecture is unique to provide highly resilient services for the Rail and Automotive applications. The latest DGNSS, RTK, PPP-RTK technologies made available by the space industry are the core technologies used by the RAN for supporting the highest possible accuracy of the vehicle compatible with the safety level requirements. Radiolabs, that has been the first to introduce the novel multilevel architecture, has now developed a new Multilevel Fault Detection and Exclusion algorithm platform to detect SiS and RAN components faults and to manage the corrections for ensuring the position of the vehicle be always within the specified confidence interval.
Furthermore, RAN will adopt the incoming RTCM SC134 standard for commercial GNSS receivers. This standard properly conceived for high integrity and high accuracy of train, car and ship applications defines the process to manage the messages broadcasted by the RAN. Based on these informations, the rail and automotive industries are liable to determine autonomously the vehicle’s position and its confidence interval. A demonstrator of the RAN system will be realised and verified in 2026. A train and a car will be equipped with their positioning device for a test campaign using the RAN network as a bench-mark for the SIL-4 and ASIL-D safety requirements respectively for the ERTMS-ETCS and the CCAM standard.
The VICE4RAIL project – Transforming Rail Safety and Efficiency: A Certification Methodology for GNSS Integration into ERTMS Using a Hybrid Virtualized Testing Environment –
This article explores the certification challenges currently hindering the integration of Global Navigation Satellite Systems (GNSS) into the European Rail Traffic Management System (ERTMS-ETCS), with a focus on train positioning applications. The work is framed within the European project VICE4RAIL (Hybrid Virtualized Testing for Certification of EGNSS in Railway Train Positioning), funded by EUSPA and coordinated by RFI. Radiolabs contributes the hybrid virtualized testing methodology, HyVICE, to combining real-world testing with a Model-in-the-Loop (MIL), Hardware-in-the-Loop (HIL), and Software-in-the-Loop (SIL) testing methodologies. This unique environment enables comprehensive and repeatable measurements to assess rare faults caused by the GNSS under operational scenarios that otherwise would require extensive and not exhaustive field tests. The VICE4RAIL architecture has been conceived to become standard, scalable and interoperable with the ERTMS-ETCS laboratory such as the CEDEX in Spain that is partner of the project. Radiolabs is developing a generalised GNSS-based train positioning, first to be tested at the RFI San Donato and to create a digital twin that afterwards will be integrated into the CEDEX ETCS simulator to assess the overall performance in any possible operational scenario in order to support the certification process.
The Role of Continuity Attribute for Train Positioning Technologies Based on GNSS and ERTMS
This research is a further contribution to the Vice4Rail project. In fact, one of the main challenges to meet the ERTMS-ETCS reliability requirements facilitating the smooth adoption of GNSS is the utilization of an aeronautical safety-critical GNSS attribute called continuity, which is new in railway technology. The main attribute is the integrity of GNSS positioning, although the time over which integrity is guaranteed without interruption, defined by continuity, which is the most demanding requirement for aeronautical applications, has not been sufficiently investigated for rail and other modes of land transport. The aim of this research is to close this gap by clarifying: 1) where the requirement for GNSS continuity comes from, 2) why GNSS continuity is needed in land transport, and 3) how GNSS-based applications can be made more reliable when needed. Using a comparative analysis, the continuity requirements in aviation, rail, maritime, and road transport have been investigated showing their importance for railways and automotive control. One of the main findings, through Markov modelling, is the improvement of the Mean Time to System Failure (MTTFsys) that for the railway safety-of-life applications can be significantly increased from about 521 h up to 5×105 h.
