A NEW METHOD OF SINS INITIAL ALIGNMENTBASED ON MINIMUM OF CUMULATED ERROR
Wu Fumei 1,2) ;and Yang Yuanxi 2)
1)Institute of Surveying and Mapping, Information Engineering University, Zhengzhou 4500522)Xi’an Research Institute of Surveying and Mapping, Xi’an 710054
Abstract:A new method of SINS initial alignment based on the minimum of cumulated error is presented for the situation of short time for initial alignment. Firstly,the mechanization and the error formulas of SINS are given. Furthermore the relation between attitude angles and cumulated errors are deduced based on position error and velocity error formulas, and the principle of fixing initial yaw angle based on cumulated error checking is given. Finally,two real experiments are carried out to show that when the initial static time is long enough, Kalman filtering and the new method can both bring about good results; but when the initial static time is very short, Kalman filtering can not obtain accurate yaw angle while the new method is able to fix the accurate yaw angle.