Towards safer rail control, command and signalling in the context of digitization

Abstract

Aim . The state of the art of railway computer-based control, command and signalling (CCS) systems is characterized by high requirements in terms of dependability, functional safety and cybersecurity under the conditions when digital transformation and challenges associated with the demand for increased competitiveness of railway transportation force the transition to new paradigms in engineering, testing, verification, validation and standardisation to facilitate and speed up the process of development and implementation. It is expected that while preserving the level of dependability and safety, at least, as it is, the industry has to enable the maximum possible introduction of innovative solutions and digital tools aimed at further automation of CCS systems to enhance the capacity and throughput of railways and the performance of systems, to minimize the impact of the human factor and reduce the number of failures and downtimes. In this context, the key factors are the interoperability (technical and operational compatibility) of systems and the technological independence of railway operators and infrastructure managers from the designer/supplier of railway automation systems, eliminating the vendor lock-in effect. Methods . The paper gives an overview of the state of the art of railway computer-based control, command and signalling using the example of the EU and provides an analysis of these systems in terms of dependability and safety in the context of migration to new grades of automation. Results . The author has considered the evolution of control, command and signalling systems in the EU using the example of the European Railway Traffic Management System (ERTMS). The analysis covered the general trends and approaches to engineering, testing, verification, validation and standardisation of railway CCS systems. The paper has overviewed the major EU research and design programmes of CCS development with the dependability and safety methodology taken into account. A special attention has been given to the methods of open engineering, remote lab testing and standardisation of ERTMS interfaces. Conclusions . In the context of digital transformation, the development of state-of-the-art railway computer-based CCS systems implies an accelerated introduction of a whole range of innovative solutions and a wide application of commercial off-the-shelf components (COTS), thus making systems more complex and being capable of affecting the dependability parameters. In order to maintain these parameters at a specified level and to minimize the impact of human factors, the railway community is increasingly using formal methods and automated means of engineering, diagnostics and monitoring at all stages of the system’s lifecycle. A major factor of dependability is the standardisation of the system’s architecture, interfaces, open source design and testing software, including the standardisation of approaches to remote lab testing of products by different manufacturers to prove the reliability of operation at the boundaries of systems of various manufacturers.