Software Evaluation System Of Rail Transportation Train Control System Based On Model-driven Software Development

The software is responsible to implement the key function together with thehardware in the train control system, standard industrial computer products hasgradually used in train. Thus the software that the responsible for implementing the corefunctions is playing an important part in ensuring the high efficiency and safety of thetrain operation. The software fault is an important factor in causing an accident, whichmight cause the life and property lose. So the research on the early software createddevelopment process, the method of models building, model test and model verificationis significant. The software in train control system is a complex system with multihierarchy of concurrency, quick response and the large state space characteristics. Theresearch suited to describe software requirements based on model-driven modelingmethod, the conversion of model status, relevant test sequence generation method,model validation and software test, this whole process had become the research focus ofevaluation theory on system-level modeling in the train control systemA dedicated formal modeling method, verification and a test sequence generationmethod are proposed according to the practical functions and needs of the software intrain control system.To the modeling method, from the point of view of requirements, a demandanalysis and function division based on model driven software architecture is proposedthe software of vehicle equipment as application object, using the standard modelingmethod UML, express the process and implementation of software systems by graph.Analysis the hierarchical structure of a specific model, and using two kinds of staticimages and two kinds of dynamic graphs in details from different layer is described,carried out on the built-in level associated with the connection.On Verification, introduces the concept of model checking, illustrating thecomputation tree logic (CTL) in the extended form of ASK-CTL used in colored Petri.From the perspective of graph traversal, depth-first algorithm is proposed to findeffective test path concept, the algorithms have used in the CPN Tools, to produce a testcase path. The actual introduction of the train control system model, propose a formaldefinition for multi-threaded graphics ThrCPN and its description, ObjCPN formalmodeling based on UML object model methods. In the hierarchical modeling methods were utilized ThrCPN and ObjCPN.Proposed the conversion method from UML model into colored Petri net,narrowing the gap between the functional models to validation scheme, simplified thecomplex process of transformation, forming a verifiable formal model.To the test sequence generating method, the method of getting the depth firstsearch algorithm is used in CPN Tools by ML language, generate test sequence. Theproblem of an excessive number of unreachable states is solved. The formal verificationmethod of generate tool case is an important tool for formal testing. Generate testsequences played a role in the software simulation for the latter testing cases. Examplepath to modify and improve checks, but also plays a key role for standardization of thecode.Finally, with the vehicle equipment software for the test object, generate the testcase and execute the test use the TestBed, compare the path of actual cases and formalmethods. It shows that the method based on model-driven software modeling methodcan realize the system state and behavior effectively, to some extent, the model statespace constrained the path, and the test sequence near with actual software functionalrequirements according to the software demand. These methods can also be used togenerate a model to guide development of application software.