Research Of CNS Environmental Error Compensation Technology Based On SINS/CNS Integrated Navigation System

Strap-down Inertial Navigation System(SINS)can realize global navigation all the time without relying on external sensors.However,the inertial navigation has the shortcomings of accumulation of time error,must be combined with other navigation systems such as Celestial Navigation System(CNS)to improve the system navigation accuracy.At present,SINS / CNS integrated navigation scheme is applied to satellites and aircrafts,and SINS / CNS integrated navigation system used in ship is limited by the influence of environmental error.For example,star sensors need to locate with the aid of external information,which will introduce errors;ship high maneuvering motion and its own vibration and even the impact cause the star map ambiguity and atmospheric refraction cause astrometry error,which introduce the environmental error;The star sensor can only work under clear weather at night,can not work at day or cloudy and so on.Therefore,it is very important to study the influence of the environment error and the correction method in SINS / CNS integrated navigational condition.This paper research the navigation error introduced by fuzzy star map and the error of integrated navigation system.The effect of position error and attitude error on the orientation accuracy of the star sensor is analyzed in detail.An SINS / CNS integrated navigation scheme is proposed,which takes the error of speed,position and attitude as the state,the attitude error is the observed,and the model of the integrated navigation system is constructed,and the influence of the error is corrected systematically by Kalman filter.The simulation results of the proposed scheme are proved validated on the MATLAB platform.The experimental results verify the correctness and effectiveness of the proposed scheme.Due to the particularity of the ship-borne environment,ships driving in the sea are affected by the waves,winds,especially in the state of war,the hull irregular vibrations,high-speed rotation,rapid maneuvering and other sports conditions,star map are likely to fuzzy.In order to achieve the processing speed of 25 frames / s and 512 × 512 pixels,a 1DWF(One-dimensional Wiener Filter)fuzzy algorithm for blurred star map is proposed,which is based on the inertial navigation provide the motion information of the carrier,the two-dimensional star map is divided into N one-dimensional M pixel sequences in the CCD sensor in the direction of movement of the carrier,one-dimensional Wiener filter is used for each pixel sequence,and each pixel represents time,each pixel value represents the value of this time,and finally the processed pixel sequence combined together to generate a processed image in the original way,after simulation experiments,this algorithm can not only solve the star map fuzzy problems,efficiency is also greatly improved.In the end,according to the proposed integrated navigation scheme and fuzzy star map processing,the real ship experiment is designed and carried out.The experiment is carried out in the lake at night,which is divided into static and dynamic tests.Static experiment is used to solve the installation error,dynamic test results by simulating the high maneuvering motion of the ship show that the SINS / CNS integrated navigation scheme and the star map processing algorithm are effective.