Qte-based Embedded Gps / Gis Vehicle Navigation System Design And Implementation

In this thesis, the GPS/GIS Vehicle Navigation System (VNS) based on the QT/Embedded GUI makes use of the Globe Position System (GPS) for automatic vehicle positioning. The system combined with the Geography Information System (GIS) and the city electronic map, can provide the Vehicle with the Real-Time Navigation information. To reduce the high price of the VNS product, a core processor S3C2410A with high quality and low price, an open source operation system Linux and an open source GUI QT/Embedded are adopted in this system. Meanwhile, a mini embedded GIS system is designed specially for the embedded VNS with the aim to provide a low price and high practicality VNS product.After introducing the research background and status quo of VNS, this thesis puts forward the way of choosing and analyzing software and hardware platform for the VNS, which emphasizes on the design of the application software of the VNS upon the Linux OS and QT/Embedded GUI. And basing upon the analysis on the software function frame of the embedded NS, we drew the conclusion that, to meet the requirement of the frame, there are three main problems to be solved: the design of MiniGIS system, the design and realization of the shortest road algorithm and the user GUI design.For of Mini embedded GIS system, the design of the tool Classes used to operate the electronic Map database was introduced firstly. Then after discussing the format of electronic map and the coordinate transformation of projection, the method of drawing the electronic map is discussed in detail. And finally the thesis carries out several functions such as zoom, drag, and distance measuring, etc. As for the design and realization of the shortest road algorithm, after solving the expression and the pick-up and building of the network structure of the electronic map, basing on the analysis of the principle and characteristic of the classic Dijkstra algorithm, a heuristic path finding algorithm is brought up, and finally the algorithm is optimized using the binary heaps and carried out in this thesis. After testing by the real electronic map and simple network, we conclude that the efficiency of this algorithm is improved greatly compared to the Dijkstra algorithm. The GUI programming does also play an important role in application software design, so we expound here the whole design process including the foundation of the development environment and the realization of the code writing.At the end, we draw a conclusion for our study, and discuss several potential methods to improve and update the embedded vehicle navigation system.