ELABORATION OF SINS POST-PROCESSING CALIBRATION ALGORITHM AND THE ANALYSIS OF ITS ACCURACY DEPENDING ON SOME TYPES OF THE AIRCRAFT MOTIONS

摘要

An important stage of the preparation of a strapdown inertial navigation system (SINS) is its calibration using turntables. The parameters of SINS instrument errors change in the process of operation, resulting in the increase of autonomous navigation errors. The in-flight usage of aiding information, namely the satellite navigation system (SNS) data, allows to estimate the instrument errors using flight data. An in-flight calibration problem is an estimation of the SINS instrument errors state vector using aiding information. The state vector includes the parameters of instrument errors. SNS data with object's coordinates and velocity is used as the aiding information. Conditionality of the calibration problem depends on the trajectory of the aircraft. A choice of such a trajectory is rather difficult to formalize using any optimization criterion. It is proposed to use two types of aircraft motions for the online SINS calibration: special evolutions that almost don't break the cruise and a "snake". Such trajectories are easy to implement and provide high accuracy calibration.