Research On Initial Alignment Technique Of Micro Slicon Inertial System Based On MTi

Inertial technic is one of the signs of high-tech development level in modern times.Low-cost,micromation and low power consumption become a potential direction of inertial navigation system,along with the development and multiple requirement of high-tech.Initial alignment technique is a very important technique.First,the thesis analysed the correlation principles of the strapdown inertial navigation which provide a basis for the research of the thesis,and also simply introduced how the system works.This thesis mainly researched into the initial alignment technique of the system on static base.This system belongs to middle or low presion navigation system,so the traditional alignment methods are not suitable.We can't complete the initial alignment only by MEMS inertial sensors,because of the low precision MEMS gyro,so this thesis research into a new initial alignment method assisted by magnetometer.It calculated a strapdown matrix which can be used for fine alignment,using the output of MEMS magnetometers and accelerometer,and the coarse alignment is completed.It completed the fine aligement using Kalman filter,estimating psi-angle of platform form random errors and disturbance,the error of inertial instrument,and also correcting the strapdown matrix obtained by coarse alignment.The basic of the research of initial alignment technique is error equation.Before deducing error equation,it analysed the error speciality and the measurement error model of MEMS accelerometer,MEMS gyro and MEMS magnetometer.So,it could get a basis to elide some errors when it was deducing the error equation,and simplified the error model on the precondition of effectively describing the error spread speciality of the system.The last part of thsis is the emulation and testing result of the pratice system. Collected the output datas of MTi,and dealt with these datas to calculate the observed quantities which were used to Kalman filter,then emulated the initial alignment process.After alignment,used the initial datas obtained by initial aligment in navigation calculation of the micro inertial system,which would validate the function of system.It validated the legitimacy and efficiency of initial alignment technique through direct and indirect way.The emulation and testing result proved that the initial aligement technique of slicon micro system in this thesis based on MTi was feasible,satisfying the requirement,and the function of system satisfied the practical requirement.The system would have a wide application foreground.