Research On Navigation System Algorithm Of Aircraft Based On GPS And MEMS

With the development of information and navigation technology,it is particularly important to accurately grasp the motion information of the carrier in real time.The attitude information of the carrier(yaw,pitch,roll)is one of the important output parameters in aerospace flight devices,ships sailing on the sea,and cars traveling on land.How to obtain the posture information of the motion carrier accurately is also a hot topic in the research field.The paper takes MEMS/GPS combined attitude measurement system as the research object,and the research focuses include the two parts of the integrated navigation algorithm and the data fusion algorithm in the integrated navigation process.The content of this paper is as follows:Explained the basic working principle of SINS,GPS and SINS/GPS tightly integrated navigation system.For SINS,a detailed derivation of the calculation process in the local geographic coordinate system was carried out,and an error equation based on Euler's platform error angle was established in the local geographic coordinate system.For GPS,the basic principle of positioning and velocity measurement was introduced,and GPS was introduced.The positioning system error has undergone detailed and in-depth analysis.Finally,the combination and correction methods of the existing MEMS/GPS integrated navigation systems are analyzed.The overall attitude measurement scheme for MEMS/GPS integrated navigation is designed and three different attitude determination schemes are proposed.The state equations and measurement equations of the corresponding measurement attitude methods are given in detail,and the algorithm verification is completed using matlab.Aiming at the divergence of the attitude of individual MEMS systems over time,a method of using MEMS and GPS loose navigation is proposed.However,the use of loose combination output correction scheme not only makes the attitude converge slowly,but also takes a long time to divergence.For the problem that the loose combination output attitude is slow to divergence,a feedback correction method is proposed.This method realizes the feedback of attitude information through quaternions.Although it can ensure that the system does not divergence for a long time,the system is slow in convergence and is not suitable for the characteristics of the rapid start of the drone;the problem of slow convergence for the loose combination feedback correction is proposed.Single-antenna principle of MEMS/GPS integrated navigation scheme.This scheme can not only ensure that the system does not diverge for a long time,but also can make the system converge quickly.For the problem that the integrated navigation cannot work properly when the visible star is insufficient,a tightly combined scheme is proposed,which can well solve the problem that the system cannot operate when the GPS visible star is insufficient.The problem of normal work.For the problem of small R-value,Sage-Husa adaptive Kalman filter divergence,introducing variational Bayesian adaptive Kalman filter.In this method,when the measurement noise R is unknown,the filtering accuracy is higher than that of the classical Kalman filter and the Sage-Husa adaptive Kalman filter,and it is not affected by the drastic decrease in the measurement noise R.Aiming at the single trajectory problem in the previous MEMS/GPS integrated navigation simulation,based on the basic principles of trajectory simulation and the dynamic equations of the carrier under different motion states,the real trajectory generator,MEMS simulator and MEMS/GPS integrated navigation simulation are designed and implemented.system.Then the actual vehicle navigation data is used to verify the performance of the algorithm.The simulation results verify that the proposed algorithm can effectively solve the corresponding problems and improve the navigation accuracy of the combined system.