Adjustment on Separate-Bias Kalman Filter during Initial Alignment of SINS

The problem of adjusting parameters with a separate-bias Kalman filter is addressed for improving the alignment performance of strapdown inertial navigation system (SINS). To reduce the load of navigation computer, the technique of separate bias is implemented. The influence of initial condition and noise covariance on separate-bias Kalman filter is analyzed. The adjustment method using which the estimates have rapid convergence, small time lag and smooth behavior is developed. Both simulations and experiments are carried out to support the analytic results. The testing results agree well with the analyses. The conclusion that the method superior over typical parameter-selection ones is derived.