Fault Model-Based Safety Test Method and Application for CTCS-3 Train Control System

摘要

As a safety critical system, train control system matters in passengers life and properties. It is important that how to guarantee the safety of train control system. Safety testing is an effective method to detect the safety holes and bugs in the system. However, most safety testing for train control system is manually executed based on expertise, which leads to a huge testing workload. Besides, manual generation will easily cause the problem of missing test cases. In this paper, a model-based safety test method is introduced, hoping to solve this problem. We select a core function of onboard system in Chinese Train Control System level 3 (CTCS-3) as representative to study the method. This function was analyzed by Fault Tree Analysis (FTA) firstly, and a set of timed automata network model of this function is built using the tools of UPPAAL, the bottom events are used to turn to fault models, injected into the whole system model. Then COVER, the real-time test case generation tool, is used to generate the safety test cases from the system model (included fault models) automatically, and states transition criteria is customized based on preferences to achieve user-defined test, the test accuracy and efficiency is improved.