Compensation for Coning Error of Pure Filtered Angular Rate Input

To improve the precision of fiber optic gyro strapdown inertial navigation system(FOG SINS),a coning-error compensation algorithm with pure filtered angular rate input is proposed.From the different coning effects of the physical quantity before and after filtering,the rule of coning error is analyzed.Combined with the angular increment algorithm using angular rate,compensation coefficients and the dominant terms of the coning error compensation algorithm in SINS with pure filtered angular rate input are derived.Results of simulation with the characteristics of real FOG IMU indicate that the proposed coning compensation algorithm is two or three orders better in precision than the traditional attitude algorithm.Coning compensation with pure filtered angular rate input is closer to the actual system.It has theoretical and practical values for improving attitude accuracy of SINS made up of angular rate gyros.