Filter Algorithms Study Of GPS/DR Intergrated Orientation

Vehicle orientation is one of the important technologies in intelligent transportation system. Global position system named GPS is of superior long-term error performance, but poor short-term accuracy, while dead reckoning system named DR has good position precision in short-term but poor in long-term.GPS/DR integrated system can plenty bring into play the respective advantage, has been a stress and an issue in China and other countries in the world.GPS/DR integration can provide position data with high precision, frequency and reliability through data fusion, on the base of analyzing the technology of GPS and DR system, this paper discusses a design of integrated GPS/DR orientation system, in which Federated Kalman filter based on theory of optimal filter fuses data from local sensors. In order to enhance the fault-tolerant capabilities and the position precision, an adaptive Federated Kalman filtering algorithm is put forward in which distributive coefficient of information is decided by PDOP (Position Dilution of Precision), and an improved federated Kalman filtering algorithm based on Unscent Federated Kalman filter is presented. The matlab simulations manifested that the position precision are improved by the algorithms.According to integrated GPS/DR with characteristic of low cost, little volume and high reliability, a new integrated GPS/DR scheme which realized by double CPU is put forward. The present system adopts the TMS320VC5410 as the main processor dealing with the filtered algorithm and uses AT89C52 to realize the acquisition of the DR and GPS signals. This thesis gives a detailed idea of the design and the composition of this system, achieves the design of hardware and software. The paper analyzes the key technology during the process of design in detail. In the aspect of hardware, the asynchronous series way is adopted to realize the data transmission of GPS and SCM, the acquisition data of DR by Signal Conditioning Circuit, the communication ways between the single-chip processor and DSP adopts HPI-8 parallel interface. As far as the software, the program adopts interrupt to manage data transmission, receival and arithmetic for the purpose of its compactness and effectiveness.On the view point of engineering application, the fusion algorithms used for vehicle GPS/DR integration are studied in systemic and the synthetical design is achieved. The results regard as the base of vehicle integration product.