Formal Modeling and Verification of the Functionality of Electronic Urban Railway Control Systems Through a Case Study

Abstract

This paper presents a formal model-based methodology to support railway engineers in the design of safe electronic urban railway control systems. The purpose of our research is to overcome the deficiencies of existing traditional design methodologies, namely the incompleteness and the potential presence of contradictions in the system specification resulting from non-formal development techniques. We illustrate the application of the methodology via a case study of a tram-road level crossing protection system. It was chosen partly because it has a simple architecture and a small number of elements, thus it fits the scope limitations of this article. At the same time, it is suitable for presenting all essential features of our methodology. The proposed solution provides a specification/verification environment that facilitates the construction of correct, complete, consistent, and verifiable functional specifications during the development, while hiding all the formal method-related details from the railway engineers writing the specifications. Using this formal model-based methodology, a high-quality functional specification can be achieved, which is guaranteed to be more exhaustive and will contain fewer errors than traditional development.

Verification of Railway Control Systems Using Model Checking and CTL, Explained Through a Case Study

“…In this section, we present an overview of our proposed methodology. For a more detailed explanation of the methodology, please refer to (Lukács and Bartha, 2022a).…”

“…1. The paper (Lukács and Bartha, 2022a) provides a comprehensive explanation of the theoretical foundation of model checking. In this study, we solely discuss the supplementary requirements for conducting model checking in FMBRSE.…”

“…Non-functional requirements and related design and verification activities were therefore not included in the research. The principles of the methodology were conceptualized in the paper (Lukács and Bartha, 2022a), hereafter referred to as Formal Model-Based Railway Safety Engineering (FMBRSE).…”

“…In this paper, our purpose is to highlight and present in detail the verification part of our framework. To assess the practical applicability of model checking in the railway domain, we developed some case studies in detail (Lukács and Bartha, 2021;Lukács and Bartha 2022a), of which we publish here the results achieved through the example of one case study (Lukács and Bartha, 2022a). For model checking, we used the UPPAAL framework, which proved to be suitable for handling the domain we investigated.…”

Integration Test Generation and Formal Verification for Distributed Controllers

“…These issues are also prevalent in the railway domain: [3] and [4] argue that the main barriers that hinder the wide adop-tion of verification-oriented MBSE/CBSE approaches stem from the lack of traceability and process integration between the high-level models and verification back-ends.…”