The Research Of On-line Calibration Technique For SINS Based On Laser Doppler Velocimeter

Currently,the laser gyro strap-down inertial navigation system is increasingly and extensively used in the military warships,warplanes,missiles,etc.The weapons has precision strike ability,rapid reaction capability and high maneuverability.On-line calibration,which is in the conditions that inertial measurement unit and the carrier stay together or the moving carrier works as before,use the certain means to calibrate the error excitation and error parameters.This paper,which sets the one-dimensional laser Doppler velocimeter and a mechanically dithered laser gyroscope strap-down inertial navigation system as the research object,makes a theoretical analysis and experimental research about the calibration method of strap-down inertial guided laser doppler velocimeter and based on the analysis of the software and hardware conditions,which includes the following works:(1)The research background and practical significance of the project are summarized,and the basic principles,research status and development trend of SINS and LDV are analyzed.(2)This paper introduces the basic equations of SINS,solving equations,error equations,and analyzes the error equations to design the Kalman filter better.Based on the basic principle of SINS and the solution method,the error equation is established,and the whole process of Verify the accuracy of the on-line calibration by build the initial alignment and the pure inertial navigation solution of SINS.(3)In this paper,the on-line calibration of the strap-down inertial navigation system based on laser doppler velocimeter is mainly realized by Kalman filter.Based on the second chapter,the Kalman filter is designed from the SINS and LDV error equations.What's more,it makes the detailed theoretical analysis of the design of the Kalman filter,which lay a solid theoretical basis for the follow-up of the simulation test and vehicle experiment.(4)This paper makes the research on on-line calibration technology of strap-down inertial navigation system based on laser doppler velocimeter.Based on the design of a 15 dimensional Kalman filter,the scale factor and the constant error term of the inertial device are estimated,so as the scaling factor and the installation error a ngle of the laser doppler velocimeter are estimated.The experimental results show that this method can improve the accuracy of on-line calibration,and it has high engineering application value.