Research On GPS/SINS Integrated Navigation Technology Based On The Direct Method

This paper takes GPS/SINS integrated navigation system used in aircraft,missiles and other high dynamic motion carrier as the background,aiming at high dynamic scenarios,the conventional indirect method taken of navigation parameter error as the state variables appears to show a much worse accuracy compare to the low dynamic scenarios.To solve this problem,the direct method GPS/SINS integrated navigation technique using navigation parameters as the estimation system state variables is carried out to research.Expounding the background and significance of the topic.The development and research status of GPS/SINS integrated navigation system’s indirect method,direct method and filter estimation algorithm at home and abroad is reviewed.The application prospect and significance of direct method in high dynamic scene are analyzed.The paper also briefly introduces the basic principles and models of GPS,SINS and indirect method of GPS/SINS integrated navigation system,which lays the foundation for subsequent research.Carring out the research of the direct method model of GPS/SINS integrated navigation system.This paper also determines the navigation parameters of position and velocity for the integrated filter state.SINS is the key subsystem of the East-North-Up GPS/SINS integrated navigation system;According to the mechanical principle of the SINS system,state transfer model is build based on velocity,position,attitude outputted by SINS,and system random error of gyro and accelerometer.The state transfer model is also verified by simulation;What’s more,according to the relationship between the GPS system output information and the state of the system,the measurement model has also been build based on the GPS output position and velocity;Analyzing the nonlinear character of the established direct method state transfer model.The estimation algorithm of particle filter based on the integrated system of direct method is designed.Carring out the software realization and simulation analysis of the direct method in GPS/SINS integrated navigation system.In this paper,MATLAB is applied to develop and implement the direct method integrated system.According to the typical high dynamic motion carrier,we design uniform rectilinear motion and high overload circumferential motion scene,and carry out the simulation and validation of the direct method performance in integrated navigation system.The simulation results show that the model of the direct method integrated system is correct.The effect of direct particle filter is better than that of indirect Kalman filter in the integrated navigation system.The indirect Kalman filtering can not effectively filter the system under nonlinear high dynamic scene,while the direct method based on particle filter can effectively filter the integrated system.