Research On Signaling At Stations Software Modeling Based On UML

Railway signal computer interlocking system is a real-time controlling system which implements the demands of railway interlocking. Being the kernel of interlocking system, it combines the techniques of communications, reliability, redundancy and 'fail-safe'. Computer interlocking software is a typical safety-critical one which ensures the traveling safety and improves the traveling efficiency. Based on the interlocking theory, UML and the model-driven architecture, the general model of interlocking system is made. It can debug at the stage of designing, ensure the high reliability and safety. Furthermore, we validate the model to ensure the implement of interlocking and complete debugging of design.On the background of interlocking system and the theoretic of software engineering, the thesis researches on the modeling of interlocking system based on UML. It has done the jobs as following:1. Based on the real computer interlocking system, it analyzes the function and requirements. Being associated with the entire framework of interlocking system, the corresponding UML diagrams were made.2. Combined with the specialty of interlocking system, the static model of structure was analyzed. Basic signaling equipments, including signal, switch, section and route, were modeled by the transferring states in the view of static structure.3. In the view of dynamic, route process, which is the core of interlocking system, was modeled. Based on this foundation and interlocking requirements, subsystems' module was modeled by UML state chart, which include selecting route, locking route, clearing signal and normal releasing route.4. Using the own function of Rhapsody, animation, the model was debugged and simulated in the level of design. It can early discover faults and release the developing cost. In order to simulate, a GUI was built, which was made by the environment of Visual Basic 6.0. By such measure, the model was debugged and validated again during the modeling period.At last, an entire interlocking model was built and debugged to complete the interlocking requirements. On one hand, the model can improve the communication between special experts and developers and ensure the reliability and safety of computer interlocking system. On the other hand, the model can help to discover the defaults in early stage. Through the above measure, the risk and cost of completing software of interlocking was reduced largely. As the shown of validating, the interlocking model is reliable and stable.