Design And Development Of Database Dedicated For Low-cost Train Control System

With the development of train control system, railway operation departments have already been engaged in seeking a method called "Low-cost Train Operation Control System"', which can increase railway transportation efficiency but reduce operating and maintenance cost. Adopting Global Positioning System (GPS) can reduce wayside equipment, so it's an effective way solving the cost problem. One of the important foundations how to achieve train location safely and reliably is special track digital map database. Therefore, researching on the design and development of special database dedicated for low-cost train control system has a high value of practical application.Firstly, this thesis introduces the key technologies which have been applied to the special database generation, designs the process of the special database. According to the one-dimensional train track profile and complex topology, the thesis puts forward a topological track model, then designs special database structure storing track spatial data and attribute data together on the basis of the real-time and simplicity. Considering the rationality of the database storing structure, the thesis proposes a multi-scale piecewise linearization algorithm with favorable adaptability aiming at the problem of curved track storing. By means of adjusting error threshold corresponding to the curved track's actual characteristics, balances the fidelity and data compression ratio, thus lays a foundation of fast storage of mass data to realize train's real time positioning.The thesis detailed introductions the development method and procedure of the special database. The main functions of this system is to generate track digital map,track configuration diagram and realizes their corresponding mapping. According to requirements of the train control system, the system is divided into two major function module both track digital map module and track configuration diagram module. The former can look over all geographic information of the segments, the latter can demonstrate the track's schematic plan in a style which the railway professionals are familiar with.Finally, the thesis realizes the generation of the special database based on the geographic information got by practical measurement from Sanjiadian marshalling station dominated by Railway Administration Beijing, and carries out the site validation, then poses some improvement suggestions.