Simulation And Testing Of Train Control System

CBTC(Communication Based Train Control)system is the mainstream of train control systems.It obtains the state of the train and other track side equipment to control the train by means of the periodic communication between the train and the ground equipment.The CBTC system requires a high safety level,so that the testing of such a system is an important task.With a simulation system and the automatic test case generation technology,it is possible to reduce the cost of testing.For the simulation of CBTC system,we need to realize the function of the whole system and get rid of the influence of the environment.For the automatic testing for CBTC system,we need to cover the whole routes of the system in order to ensure the completeness of the test case set.Furthermore,we also need to try to reduce the redundancy at the same time.The existing research cannot satisfy all the above requirements.Therefore,this article designs and implements a CBTC system software simulation system;proposes and optimizes an approach for test case generation,which has solved some problems in existing work.The following achievements are as follows.1.This dissertation designs and implements a software simulation system for CBTC system.The design of the simulation system focuses on the three core functional modules of CBTC system,i.e.,zone controller module,computer interlocking module,and train protection module.This paper analyzes the composition of the modules and the requirement of each module in actual scenarios,in order to get the logic flow of each module when a train is running.Then,we design and implement the CBTC simulation system on the basis of this analysis.2.This dissertation proposes and optimizes an approach to generate the test case set automatically.The paper gives a formal description of the objects in actual test scenario according to the UML sequence diagram,and improves the transformation algorithm to the ETDFA model with the characteristics of CBTC system.With this algorithm,we can obtain the intermediate model.The paper uses depth-first search to generate test case set,and optimizes the algorithm to remove redundant data in test case set according to the idea of data flow testing.3.This dissertation designs experiments to evaluate the effectiveness of simulation system and the test case generation approach including the optimization technology.These experiments show that our simulation system meets the functional requirements and the optimization of test case generation method is effective in the scenario of the automatic test case generation for train control system.In conclusion,the method proposed in this paper is a CBTC system testing method,which can solve the existing difficulties in CBTC testing.This method has an application value for the actual rail transit signal system testing.