High-Precision Fiber-Gyroscope Inertial Navigation System Technique For Warship

Currently, the optics gyro strapdown inertial system is taking the place of the machinery gyro platform inertial system gradually. In this period, inertial navigation system of ship has to provid highly-accurate navigation orientation independently during long time. Fiber optical strapdown inertial navigation system is a complicated system which has many sensors. Its key technology involves numerous aspects. This article engages in sympatric calibration, initial alignment, system error restrain technology which is based on the elevation of actual demands of ship fiber optic gyroscopes strapdown navigation system。The main res earches are done as follows:At first, we construct error models of both fiber optic gyroscope and accelerometer inertial meters. We analyse the error model and point out the localization which is based on traditional error model. On the base of this analysis, this article advances a new systematic calibration plan which separates the fiber optic gyroscope errors from accelerometer errors. It designs the filter respectively. The calculation quantity is reduced, at the same time, of kalman filter, it carries out the decoupling of fiber optic gyroscope and accelerometer error parameter which improves systemic observation.Secondly, this article demonstrates the compass loop alignment algorithm of fibre optical strapdown inertial navigation system. It accomplishes the design of compass loop parameter and the analysis of the error on onstatic base. It analyses deeply the influence to compass loop calibration precision on moving base by speed, acceleration and latitude error. Using the method of equivalent device error, it advances compass loop alignment methods based on apparatus error compensation and external speed compensation. Besides, it carries out the simulate analysis and experiment test which shows that it is suitable on moving base..Thirdly, alignment methods are studied when the base is interfered by swaying in moorage. This article analyses and constructs a modeling to swing and suring of the carrier. Then comparison is done of the analytic coarse alignment, "leveling and direction estimate" coarse alignment and inertial frame coarse alignment methods which points out that inertial frame coarse alignment plan is more suitable for engineering. Besides, it apllies frequency domain analytic method to analysis the influence of oscillatory drift, and then t and parameters of he alignment system are designed. Finally, Kalman filter alignment method in disturbing condition is studied. When the coarse alignment is finished, taking high pass fliter to speed output of inertial navigation system, we get the accurate instantaneous speed information and take kalman alignment using the speed error as the observation value. It truly heightens the precision of kalman fliter alignment in disturbing condition.Finally, damp algorithm is introduced to restain the surging errors of the inertial navigation system, and then the network frameworks and parameters are designed for level damp and azimuth damp respectively. In order to restrain the overshoot phenomenon caused by destroying balance condition in the conversion process, we analysis the overshoot deeply, and we study the theory of overshoot phenomenon and decrease the overshoot in the conversion process by damping coefficient gradually. Making use of the diversity of SINS's mathematics platform, it advances a rapid damp plan to deal with the problem of damp network's convergent time which gets an effective result. The SINS's damp plan is simulated and tested.This article carries on a deeply research through four aspects as follows:systematic calibration, compass loop alignment on moving base, alignment in swing and suring condition and SINS's damp network. It Heightens SINS's entire precision and ability of dynamic adaption. This article makes important academic significance and it has pracaticality.