Research On Navigation Algorithm Of Strapdown Inertial Navigation System Based On Quaternion

The strapdown inertial navigation system(SINS)is a mathematical platform inertial navigation system with high precision and high reliability,which can provide high precision motion parameter information without any external information.It is widely used in many fields such as aviation,spaceflight,navigation,missile and so on.Because of the strong nonlinearity and uncertainty of INS,how to improve the navigation accuracy of strapdown inertial navigation system becomes a hot topic in the world.In this paper,from the point of improving the precision of navigation system,this paper makes a deep research on the establishment of the attitude error model and nonlinear filtering algorithm based on quaternion model,high order moment matching,Gauss process and Stirling interpolation method.Aiming at the limitation of the quaternion model in the navigation solution,the paper constructed the attitude transformation model of dual quaternion and multiplicative error equation of dual quaternion by utilizing its characteristic to combine the rotation calculation and the translation calculation altogether.By comparing the simulation results through Matlab simulation,it is proved that the multiplicative dual quaternion has better effect in the system with multiplicative error.Aiming at the navigation system's problem of strong nonlinearity and statistical characteristics of transfer error,the high order moment matching method was utilized to calculate the average skewness value and peak value of the predicted sampling points set,and their weights in the view of the probability distribution,and the high order moment matching unscented Kalman filter(HoMM-UKF)is raised.The simulation results show that the HoMM-UKF algorithm is feasible and accurate in strapdown inertial navigation system.Then,aiming at the problem of nonlinear computational complexity of integrated navigation system,by using Gauss process modeling method,the paper has constructed non-parametric GPs model,and proposed the Gauss-process cubature Kalman filter(GPs-CKF)algorithm and the enhanced GPs-CKF algorithm.The simulation results show that compared with the traditional CKF algorithm,the enhanced GPs-CKF algorithm and GPs-CKF algorithm have obvious advantages on computational efficiencyIn the light of the Krein space extended Kalman filter(EKF)of the linearization problem of the Jacobin matrix computational complexity.The Stirling interpolation Krein space EKF algorithm is proposed.Based on the velocity matching transfer alignment model,the velocity and attitude errors of the main inertial navigation system and the sub inertial navigation system are taken as the observation,and the system state and observation model are established.The extended Krein space Kalman optimal filtering algorithm is used to estimate the nonlinear filter,which can realize the fast and high precision calculation of the transfer alignment.