The Study On The Application Of Rotation Vector To GFSINS

When body is under coning motion, the quaternion algorithm for attitude updating of Strapdown Inertial Navigation System cannot calibrate the coning error, but the rotation vector algorithm works well. So the paper introduces the rotation vector algorithm into GFSINS, and in allusion to its characteristics to resolve the problems, which come out from the application. The main work is following:Fist, the paper descripts the work principle of GFSINS: develop the output formulation of accelerometer being non-centroid, and how to attain the angular acceleration and angular velocity and linear acceleration being centroid with the outputs of accelerometers being non-centroid.Second, the paper studies on the coning error and the rotation vector algorithm: study mostly on the resource of the coning error, and provide that the inherent fault of algorithm is the resource of the coning error, and the noncommutativity error is one of the main factors bringing the coning error, then develop the optimal Four-Sample Rotation Vector Algorithm.Last, the application of rotation vector algorithm to SINS needs to sample the body relative angular displacement, but the GFSINS cannot meet directly the need. It is very important to apply rotation vector algorithm to the GFSINS that how to attain the relative angular displacement and meet its precision and updating frequency. In allusion to the characteristics that the GFSINS may get angular acceleration and angular velocity at the same time, and the precision of angular acceleration is higher than angular velocity's, the paper provides a method to obtain the relative angular displacement with the angular acceleration and angular velocity which are bordered upon. The results of simulation show that the method is effective.