Research Of The Transfer Alignment Base On Ship FOG Strap-down Navigation System

Transfer alignment is a dynamic alignment, which uses high precision Master Inertial Navigation System (MINS) to calibration the non-alignment Slave Inertial Navigation System (SINS). Transfer alignment at the initial application is used in Aircraft-Missile Launcher, and later introduced to the initial alignment field of ship-borne equipment. Transfer alignment of ship's SINS in addition to the general dynamic rules; it also has its own characteristic and nature. This paper will focus at these characteristic and nature of the transfer alignment mainly.First, this paper gave the strap-down inertial navigation system dynamic base rate error equation, the position error equation, the attitude error equation, the gyroscopes and accelerometer's error model, and inferred the rate matching, the angular rate matching, the velocity plus angular rate transfer alignment matching method error model. The paper in view of the rate matching, the angular rate matching, the velocity plus angular rate matching to carry on the simulation analysis, the simulation result showed that in ship's transfer alignment process, the overall comparison, the velocity plus angular rate matching method effect is quite good, with short time of estimated misalignment angle and high of the precision, receives dynamic flexibility distortion, the lever arm effect as well as the swing scope and the state of motion influence is small; When the large scale swing Existence, it may also choose the angular rate matching method, and the rate matching method may be used to estimate the leveling alignment angle fast.Secondly, this article according to the accuracy of leveling alignment is high and time is short, but the accuracy of heading alignment is not the ideal situation generally in the method making use of matching in the past, so we take a algorithm of azimuth alignment method based on the data of Inertial measure part. According to this method, we regard the leveling alignment information as known quantity, deducing out the theories and simulating by Matlab, the results show that, finally indicated that so long as has the small scope to swing this method namely feasible, this azimuth alignment method estimates the accuracy of heading alignment is high, and dynamic flexibility distortion, the lever arm effect as well as the swing scope do not affect large.Finally, the rate matching method in-the-loop simulation test carried out a major laboratory three-axis turntable, the vehicle carried and ship three experiments, given the experimental data indicates that the experiment has made the quite satisfactory progress.