Research On Safety Analysis Of Train Control System In Requirements Phase Based On UML-NuSMV Model

ABSTRACT:The railway has become one of the most important infrastructures and the most popular means of transport in China’s transportation system. As the core technology of the railway system, Chinese Train Control System (for short, CTCS) plays the key role in the railway transport to ensure the safe and effective operation of the trains. Once the safety problems of CTCS are emerging, it will likely to cause traffic interruptions, and even train crashes. Therefore, it is particularly important to perform the scientific and effective safety analysis on the system in requirements phase that is the early phase of system life-cycle.Research on CTCS adopts the international general method of "antecedent standard", that is to complete the development of system standards specification first, and then to guide the follow-up researches. Therefore, we adopt CTCS-3level train control system requirement specification as the research object in this thesis. Meanwhile, we focus on modeling analysis and formal verification, then establish fault model to do safety analysis. Main researches includ the following points:1. We adopt Unified Modeling Language to model the early train control system from the system requirements, the static structure and dynamic behavior, and extend the modeling language to enhance the modeling ability.2. With conversion rules, UML model can be converted into formal NuSMV model, so that we can use formal techniques to complete the requirements specification verification to lay a foundation for the later safety analysis. This paper also defines failure mode failure sign marks to complete research on safety analysis of train control system requirements phase based on UML-NuSMV model.3. We develope software for safety analysis of train control system in requirements phase:RMTool. The tool is essentially a plug-in, which can be integrated into the RSA platform. With the relevant interfaces to link the formal tool and UML model, it implements three main functions including model conversion, property verification and security analysis, and it will greatly assist to expand the content of this paper.