Online Testing Safety Function Of New Train Control System On-board ATP

The train control system is the key to ensure train safety and improve transportation efficiency.With the development of social economy,the railway network is continuously growing,and the public traveling demand is constantly increasing,which put higher requirements on the train control system.In recent years,China,the United States,Europe and other countries and regions have been carrying out a lot of research on the train control system.The development trends are mainly as follows:(1)enhancing the function and processing capability of the on-board equipment;(2)optimizing the system structure and function allocation,and reducing the system building and maintenance costs.The new train control system featuring technologies such as train-to-train communication and autonomous train control can reduce the number of wayside equipnent and optimize the control process,which has become a research hotpot.As the scale of the on-board software of the new train control system increases,the function correctness assurance is crucial.The offline testing technology is commonly used to verify the on-board software functions of the train control system.However,the offline testing method using the artificial experience to compile testing cases is difficult to adapt to the verification requirements of the new train control system.On the one hand,it is hard to verify the consistency between the manual test case and the safety requirement,which means the test primitive cannot be verified.On the other hand,changes of operation scenarios,application structures,and functional requirements are difficult to be responded in time to follow up system iterations.In addition,complex software logic dramatically increases the number of offline test cases,and makes management,application,and evaluation of the test cases difficult.In this paper,the on-board ATP safety function test of the new train control system is taken as the research content.Combined with the formal modeling,verification and conforrnance relationship theory and tools,an environment-related online conformance testing scheme suitable for the new train control system is proposed and tested through specific applications.It also analyzes availability,verifiability,accuracy,flexibility and sensitivity of the testing framework.The specific research includes:(1)The composition of the new train control system is deeply analyzed,and the functions of the subsystems and related interfaces are studied.Based on the structure and safety functions of the on-board ATP,the typical operation scenarios related to the on-board ATP are analyzed,and the internal module-level interaction process of the on-board ATP is described.(2)The time system formal modeling theory,the conformance relationship theory and corresponding tools,UPPAAL and TRON are introduced.The on-board ATP online conformance testing method combined with the train control system safety life cycle is proposed.It can realize automatic generation,automatic execution and automatic result judgment of online test cases of the on-board ATP safety functions.(3)A modularized formal testing model covering multiple operation scenarios is developed combined with the timed automaton theory and corresponding modeling tool UPPAAL,based on line data containing three stations and two segments.The on-board ATP simulation software and the testing adapter middleware are designed with Golang language.Therefore,an online testing application framework for the on-board ATP is established,and the evaluation method and indicators using the mutation analysis are proposed.Finally,two typical operation scenarios are selected to explore the application of the testing framework,and the performance of the test framework is evaluated through test results and data analysis.The experimental results show that the online conformance testing method can support the testing requirements for complex operation scenarios,and can find the inconsistency defects of the device under test in time and accurately.At the same time,the verification of safety requirements can support the rapid iteration of the system and provide a strong guarantee for the safety of the train control system.This paper has 33 figures,18 tables and 79 references.