Research On Generation Method Of Digital Track Map For Train Control System

Introducing GNSS (Global Navigation Satellites System) and GIS (Geographic Information System) information into Train control system can improve the accuracy of train positioning, reduce the number of line side equipments, achieve the device virtualization and cut down the cost of construction and maintenance, it has become an important development direction of the Train control system. Digital track map, which is constructed low-cost, as a stable and effective information carrier, is an important application of Geographic Information System in rail transport and plays a fundamental role in the improvement train positioning accuracy and auxiliary of train operation control. In order to achieve high-precision train positioning and accurately control of the train, reasonable and effective digital track map must be researched.The dissertation is based on the analysis of line features and the topology of the railway network, and actual station and line data are taken as examples. The building of track data model, the generation of track data, the visualization of track map and the verification of digital track map for train control system are researched in the dissertation. The main works of the dissertation are as following:The data model of digital track map for train control system is build. According to the functional requirements of digital track map in the train control system based on GNSS, the data organizational structure of track map is constructed on the basis of the characteristics of the railway network, then the overall generation process of track map is proposed, and the line data and the attribute data are designed according to the process. At last, the associated matching algorithm is designed to realize the relevance of line data and attribute data.The generation of track data is researched from the filtering of line data points, the acquisition of linear parameters and the conversion between two track models. The filtering algorithm of line data points is proposed based on the judgment of the line form to achieve the automatic segmentation of the line, then least squares method is used to fit the circular curve and straight line and the transition curve is fitted with cubic polynomial to complete the segment fitting. The validity of the algorithm is proved by the calibration results of fitting error. Then, the conversion from two dimensional geographic model to one dimensional topology model is achieved.The storage and management method for track map data is proposed and the visualization and verification of digital track map are completed. XML (eXtensible Markup Language) is used as a storage format for track map data on the basis of the data model and the data generation, and combined with the track map data, the MapX components and C#are used in Visual Studio environment to complete the functions of GIS map display and operating. Then, making use of related track map data, the static and dynamic display of topology diagram is realized to verify the validity of the data, and making reference to Graph traversal algorithm, connectivity verification algorithm is designed to verify the correctness of the track map data.