SCADE Supported Software Development Of Zone Controller In CBTC System

Zone Controller (ZC) is the core ground control equipment of Communications Based Train Control (CBTC)system.ZC is responsible for calculating the train movement authority. ZC is a huge complex safety-critical system, and it is difficulty to describe, to design, and to validate.Recently, model-based software development method is rising. In this paper, SCADE model-based development is used for software development of ZC.The main work of this paper is as follows:1)Study the safety critical systems and related safety standards of the rail traffic control system. An analysis on the advantages of model-based software development is given. Then the SCADE toolkits are introduced.2)Theoretical basis of SCADE,Synchronous programming theory is studied.The grammar rules and the model of LUSTRE language are described. Safe state machine and data flow model is researched as the models approach of LUSTRE.Then simulation and formal verification as the two validation ways of synchronous programming theory is researched.3)The SCADE model of ZC has been built. Several typical scenarios of zone controller are analyzed.The main functions of the Zone controller are designed. SCADE is used to build the models of these functions.The train management function is modeled by safe state machine;the route matching and MA calculate function is modeled by data flow model.4)SCADE test and proof methods have been researched. Safety analysis for ZC has been performed. The SCADE simulation module has been used to test the models of ZC. The SCADE verifier has been used to validate the safety property of ZC. At last, the advantages of development by SCADE are summarized.