Research On Fault-tolerant Method Of Multi-source Fusion Navigation Syste

Due to the complementary characteristics of global satellite navigation system(GNSS)and strapdown inertial navigation system(SINS)in principle and structure,GNSS / SINS integrated navigation system is widely used in daily production and life and even military aspects.Nevertheless,as the application environment becomes more and more complex,GNSS/ SINS integrated navigation system can not provide users with continuous and reliable navigation information because the satellite signal is easy to be interfered and deceived,which makes the independent inertial navigation system produce errors with time due to the influence of its own principle.How to improve the reliability of navigation system to ensure users’ need for positioning and navigation services in production and life has become more and more important.By enhancing the anti deception ability of satellite navigation receiver and combining the advantages of different navigation sensors,this paper studies a multi-source fusion navigation system with fault-tolerant performance,so as to improve the ability of the navigation system to provide continuous and reliable navigation services in complex environments.This paper takes a national key project as the research background,takes the multi-source fusion navigation system of GNSS and sins combined with other external sensors as the research object,and carries out the research on anti deception and multi-source fusion faulttolerant methods based on interactive multi model filtering under the application environment of land carrier.The main research contents are as follows:1.The common navigation coordinate system are introduced.The global satellite navigation system,strapdown inertial navigation system,magnetic compass,altimeter and odometer are selected as the navigation information sources to study the multi-source fusion navigation system,and the navigation principles of each sensor are introduced respectively.Taking sins as the common reference system,the multi-source integrated navigation model is established,and the fault-tolerant federated filtering algorithm is designed.The effectiveness of the algorithm is verified by simulation.2.Aiming at the problem that the traditional satellite navigation receiver position,velocity and time(PVT)solution adopts the centralized Kalman filter method to centrally process all the observations,and when one of the satellites is deceived,it is impossible to distinguish and isolate,a fault-tolerant federated filter structure for the receiver solution layer is designed in this paper,which disperses the observations,The fault diagnosis algorithm is used to identify and isolate the deceived satellite and improve the anti deception ability of the system.Simulation results show that the algorithm can improve the fault tolerance of the system in the case of single satellite or few satellite deception.3.Aiming at the situation that the model of multi-source fusion navigation system changes in complex environment,so that the filters with fixed model parameters can not match completely,resulting in the decline of navigation accuracy,a multi model fault-tolerant federated filtering algorithm is designed in this paper.The GNSS / SINS sub filter that has the greatest impact on multi-source fusion navigation system adopts multi model adaptive filtering algorithm,Several filters with different parameters are used to approximate the dynamic performance of the system.Simulation results show that the filtering algorithm designed in this paper can effectively improve the accuracy and reliability of the system.4.In order to verify the effectiveness of the algorithm designed in this paper in practical navigation applications,a plug and play multi-source fusion navigation system based on DSP is built.The real data are collected through the sports car experiment,and the hardware in the loop simulation experiment is used to verify that the fusion algorithm can effectively improve the accuracy,continuity,reliability and fault tolerance of the navigation system,which lays a foundation for the implementation of the algorithm in practical engineering application.