Research On Test Method Of Safety Computer Platform For The Train Control System

Safety computer platform which is closely related to the zone controller and the data storage unit is one of the core equipment and the important safety unit in the train control system.In order to break the technical blockade and possess an independent safety computer platform,the next generation of train control safety computer platform has been developed by the Beijing Jiaotong University Key Laboratory of rail traffic.In order to meet the needs of the next generation safety computer platform test,Safety computer platform test method is studied in this paper.A general mixed testing method for safety critical systems is proposed in this paper,for the reason that the universality of test methods can not be satisfied by different test methods used in each test phase or unity can not be achieved by the separation of track with test,and it is applied to the test of safety computer platform.First of all,five main technical methods are designed for the mixed testing methods in this paper.The main technical methods includes system requirement extraction,the construction of information flow can be integrated of the system,model transformation and analysis,auto-generation of the test sequence,structure and demand coverage analysis of test result.The present situation and the realization process of the methods are analyzed and introduced.Secondly,the mixed testing method is applied to the safety computer platform test.Safety computer platform system level,subsystem integration level and unit module level functional characteristics group are decomposed from the two aspects of the test model and system operating mode state.Then the list of requirements for safety computer platform is extracted.rational rose is been used to draw a safe computer platform use case diagram.The transformation rules of the case diagram with the class diagram and the state transition diagram with the class diagram are compiled,then class diagram and state diagram of safety computer platform are converted.The requirements of safety computer platform are extracted,the data structure of safety computer platform is compiled,and the demand hash value as the demand of the digital fingerprint for subsequent demand tracking.is generated by the improved SHA-1 algorithm.All of these achieved that information flow of a safety computer platform can be integrated.UML class diagrams,state diagrams and NuSMV meta models are compiled,the transformation rules of UML model and NuSMV model are analyzed and compiled from the perspective of meta model,meta model is written in KM3 language,the conversion program is written in ATL language,in the Eclipse environment of the ATL platform,the ATL conversion framework is used to convert the state diagram of the safety computer platform to NuSMV model and the SMV program is analyzed.the CTL describes the nature of the safety computer platform that meets the MC/DC test coverage criteria is added to the SMV program SPEC module,and the test sequence is generated by NuSMV model checker.Finally,the safety computer platform test system is built,the test fixture and test software are designed,The integration of the application of the mixed testing method and the requirement tracing with testing in the test phase of the safety computer platform are achieved.Then the test results are analyzed by structure and demand coverage analysis.The test results show that the mixed testing method can be applied to the various stages of the safety computer platform,and it can realize the unification of the test with the requirement tracing.