Research On Geomegnetic/SINS/GPS Micro Integrated Navigation System

The traditional integrated navigation system is mainly composed of strapdown inertial navigation system and global positioning system.but the error of strapdown inertial navigation system is accumulated with time and the GPS signal is easy to lost lock.This paper introduces geomagnetic navigation to make up for the shortage of strapdown inertial navigation system and GPS,and designs the Geomagnetic/SINS/GPS micro integrated navigation system according to the requirement of miniaturization.In this paper,the basic principles of geomagnetic navigation,SINS and GPS are mainly studied.The spherical harmonic model of geomagnetic field is studied,the algorithm of geomagnetic attitude measurement is deduced,and the principle of geomagnetic navigation is introduced.Based on the basic principle of SINS,the navigation algorithm is deduced and the error model of SINS is analyzed.This paper introduces the composition of GPS system and analyzes the error model of GPS.In this paper,a wavelet transform is introduced to improve the accuracy of geomagnetic navigation by denoising the signals measured by magnetic sensors.By analyzing and comparing several algorithms,the wavelet domain threshold filtering algorithm is chosen to denoise the magnetic signal.According to the combination method of SINS/GPS and the characteristics of the system,this paper puts forward the loosely coupled design of federated kalman filter based on Geomagnetic/SINS/GPS system,which satisfies the requirement of real-time and reliability.In this paper,the federated filter based on the Zero-Reset structure is designed,with SINS as reference system,the SINS/GPS filter and the SINS/Geomagnetic filter are designed respectively,and the feasibility and superiority of the algorithm are verified by simulation experiment.In this paper,the navigation hardware platform of micro-type combined system based on DSP is designed,including hardware schematic design,PCB layout design and system hardware and software debugging,and the hardware circuit of main function part is analyzed in detail.And the combined navigation system is validated by the actual test experiment.The experiment proves that the integrated navigation system can satisfy the practical application requirement,and greatly improves the navigation accuracy and reliability of the integrated navigation system.The system also has the characteristics of miniaturization,low cost and low power consumption,and has certain engineering practical value.