Research On Strapdown Inertial Navigation Algorithm And System Simulation

Strapdown inertial navigation system (SINS) is a kind of advanced inertial navigation technology, and it is the developing direction of inertial navigation.Because SINS has a series of advantages, it has become a trend that SINS will take the place of platform inertial navigation system in new century. To improve the accuracy level of SINS, one way is to design and make high precision inertial instruments, i.e. gyros and accelerometers. But the inertial instruments' performs are limited with material and technical level. Another way is to design and use optimal algorithms. Thus, it is necessary to study the high precision algorithms for SINS.In the paper, the fundamental theory of the SINS and several attitude updating algorithms are introduced first.Then the following problems are studied:1. It is studied that how the coning error occurs for SINS. It is discussed that the equivalent rotation vector algorithm and its derivative corrected attitude algorithms and optimized attitude algorithms. Then those are emulated in Matlab. And we have also given an improved optimized attitude algorithm based on rotation vector.2. The sculling error in the velocity calculation is studied and the sculling compensation algorithms are derived. We also dedued the sculling compensation optimization algorithms in the sculling motion environment. For testing the sculling correction algorithms' performance, several simulations are given and the simulation results show that the sculling compensation term in the velocity integration algorithms can not be neglected for the high accuracy SINS in highly dynamic environments. At the base of this, we study the scrolling error in position calculation.3. The paper studies the mathematical model of gyro and accelerometer, the method of calculation of navigation, solution method of generating flight trajectory data in detail. Then the paper develops the system of generating flight trajectory data and the system of real-time simulating strapdown inertial navigation with MATLAB/Simulink.The simulating system synthesizes the inertial sensor simulation and strapdown inertial navigation simulation. And we have used the improved optimized attitude algorithm based on rotation vector in the system. The result shows that the simulating system is steady and reliable, and the simulating result is satisfying.