The Design Of Strapdown Inertial Measurement Unit Self-calibration System

With the application and popularization of inertial navigation technology in the sea,land,air,and other fields,it is eternal invariable research focus to the scientific research personel to improve the precision of navigation systems.As the core components of the navigation system,the measurement performance of inertial components which directly affect the final accuracy of navigation.The key function of the strapdown inertial component self calibration system is to provide transposition for the strapdown inertial component by the biaxial rotary turntable,so that the strapdown inertial component can measure the specific inport in different positions.The system can complete the transposition and slove the error parameters of the strapdown inertial component by once power.This article set about the self calibration technique of strapdown inertial components,researched the two axis turntable control system and calibration technology of inertial components respectively,and verified the system finially.The specific contents include the following aspects:(1)This paper introduces the development of strapdown inertial navigation system briefly and analyses the self calibration system of strapdown inertial components systemiclly based on the research of inertial components of the self calibration technology.It is discussed mainly from the two aspects of biaxial calibration turntable control system design and the strapdown IMU calibration plan,and analysed self calibration error and calibration time of the strapdown inertial component.(2)The control performance of the biaxial rotary turntable,which is indispensable part of the strapdown inertial component self calibration system will directly influence the accuracy of calibration of strapdown inertial components.It is proposed the turntable control program based on biaxial turntable control theory,established the model of control system and analysed the performance of the control system while discussed control system of control algorithm.Considering the actual situation of the biaxial rotary turntable design,it is also studied the turntable friction torque and compensated the friction compensation by designing the controllor of backstepping mode.(3)Aiming to calibration scheme and the strapdown IMU calibration principle,the paper mainly analyse the static error model of inertial components,and focus on the strapdown IMU calibration translocation machinery arrangement and the inertial components ideal input in the different positions.In addition,in the need of processing of inertial components output data,the data spectrum is analysed and the data of several different filtering technology is studied.Finally,with the help of inertial components static error model and calibration translocation machinery arrangement,the components error parameters are deduced by the error parameter identification method and the least square method respectively and sloved eventually.(4)This part verified the design of the turntable control system by the simulation firstly.And the discrete time invariant system is created with the help of the error model of inertial devices,then the self calibration scheme is validated by analysing the system observability and degree of observability analysis of inertial components in theory.Secondly,the self calibration scheme is validated by experimenting and the inertial components error parameters are solved successfully by using error parameter identification method and the least square methodseparately.Then it puts forward the inertial components error parameter accuracy verification scheme.Finally,the inertial component self calibration results are compared and validated while the self calibration performance and accuracy are verified,and the calibration time and the calibration error are quantitatively analysed to draw the conclusion.