Research on errors self-estimation of INS in motion base

The higher precision outer information is commonly applied to correct the errors of an INS (inertial navigation system) in order to ensure output precision of long-time-working INSs. Based on the analysis of errors of the INS motion base, the method for errors self-estimation is proposed to improve the working autonomy of an INS. The analysis results shows that if the INS used in a ship works in the outer level damp state, the level static errors approach zeros, and the azimuth, speed and latitude errors are periodical oscillations with the same period as the self-rotation period of the Earth. The longitudinal stabilization error also contains the oscillation portion with the Earth period. According to these error characteristics and observability, nonlinear least square algorithms can be used to resolve speed recursive equations and outer information is not needed to compensate the INS errors