An Automatic Test Method And Result Analysis Of The ATP System Based On Requirement Modeling Development

ATP(Automatic Train Protection)software system is the kernel of railway installation to ensure safe train operations.Rigorous requirement testing is demanded to check whether the software behaviors conform to its requirements specification.Then do some scene test to ensure the safety related function.In the Rigorous test methods,there are short of automatically,high coverage rate,full safety scene test case to systematic test the ATP softwareIn this paper,we propose an automated requirement testing method for ATP software systems.A tool called ATPDL Tester was developed for supporting the automation of the method.First,we dedicated a domain-specific language ATPDL(Automatic Train Protection Description Language)to establish the ATP software model,and abstract the VDDs(variable dependency diagrams)and STDs(state transition diagrams)from the specification to visualize the interactions between variables and states of individual variables for effective specification validation.Second,both the scenario-based and specification-based testing technologies are provided by the method.Testers can specify the concerned safety-critical scenarios of a train using the dedicated ATPDL-SL(Automatic Train Protection Description Language-Scenario Language)for test case generation or directly derive test cases from the specification using the MC/DC(Modified Condition/Decision Coverage)coverage criterion.The ATPDL-SL is a type of scene language,which is precisely,easy to learn,can translate to test platform driver script via ATPDL Tester tool.Finally,in order to comparing the expected outputs derived from the specification and the test platform execution results,a domain-specific language actuator was been dedicated.The ATPDL Tester can compare the expected outputs and the test platform execution results and finally give a result about the realization is as same as the requirement model.The case study demonstrates that the method and tool significantly facilitate the current ATP requirement testing.Compared with the previous technologies adopted in the CASCO Ltd.,more errors in the specification are detected and more software defects are discovered with fewer time and human labor costs.The ATP software developed and tested by the method and ATPDL Tester tool passed the TüV Rheinland(a third party independent safeguarding Authority)test witness and in line with EN50128 SIL4 safety certification.