Simulation Of Strapdown Inertial Navigation System And Integrated Navigation System

Strapdown Inertial Navigation System (SINS) leads the trend of inertial navigation systems currently. Compared with Platform Inertial Navigation System, SINS is smaller in size, lighter in weight, more reliable and cheaper. However, the inherent defects Strapdown Inertial Navigation System because of the system error of SINS accumulating with time. Integrated Navigation System is commonly used to improve the accuracy and reliability to solve this problem. Especially the combination of SINS and GPS navigation has been widely used in navigation field.The basic principles of system alignment are introduced. The realization methods of Coarse Alignment and Precision Alignment are discussed in detail. The formulas of system posture algorithm, Speed Calculation and Position Calculation are studied. Simulation software of SINS is designed. Based on the actual characteristics of inertial navigation system, different functional simulation modules are established with the MATLAB environment, such as Vehicle Trajectory Generation Module, Inertial Components Modules, Kalman Filtering Module and Strap-solver Module. Then, follow the system's work processes, the initial alignment and Navigation Solution are carried out. And the work of the navigation process is simulated. The results show that the accuracy of navigation parameters is very good in the short term. But the system error accumulates with time. SINS can hardly meet the requirements of longtime.To solve the problem of SINS, the integrated navigation system design method is studied in this paper. The working principle of SINS/GPS integrated navigation system is analyzed. And the integrated system Measurement Equation and Equation of State are established with the application of Kalman filtering based on Indirect Feedback Correction. The simulation of integrated navigation is achieved based on MATLAB. The advantages of two types of navigation method are played out by SINS/GPS integrated system. The phenomenon of SINS Error Divergence is overcome. The accuracy of navigation system is improved. SINS / GPS integrated navigation system's performance is superior to strapdown inertial navigation system.