Schuler oscillation error compensation method for low-speed SINS

The real-time accuracy is always the key technical index of strapdown inertial navigation system (SINS). However, Schuler oscillation errors in system errors reduce the precision of SINS a lot. Aiming at compensating Schuler oscillation errors of SINS, a Schuler oscillation error compensation method For Low-speed SINS is proposed in this paper. Retaining autonomy of SINS, this method can compensate Schuler oscillation errors of low-speed maneuvering SINS effectively. According to the motion characteristics of low-speed carrier, Variable-foucault-oscillation-frequency SINS (VSINS) is obtained by compensating the harmful acceleration related to the earth rotation rate with weighting coefficient k. Then, three VSINSs with different Foucault oscillation frequencies are obtained by selecting three different weighting coefficients, and the mean value of the output result of the three navigation algorithms is used as the navigation result of the whole system. The mean square error for the amplitude of compensated Schuler oscillation becomes relatively minor. Computer simulation results show that the method has good performance in compensating Schuler oscillation of SINS, which improves the real-time accuracy of SINS effectively.