Anti-disturbance self-alignment method for dual-axis rotational inertial navigation system under marine mooring conditions

Under the marine mooring conditions, the inertial navigation system (INS) is often disturbed by angular and linear motions, and it is difficult to perform self-alignment with high accuracy. To solve this problem, an anti-disturbance self-alignment method for dual-axis rotational INS is proposed. The method transforms the self-alignment problem into an attitude matrix solving problem, so as to deal with the disturbance of angular motion. By analyzing the relationship between the amount of measurement data and the accuracy of self-alignment, the optimal integration time is designed and a partial integral algorithm is proposed. Furthermore, the influence of initial velocity error on self-alignment under linear motion disturbance conditions is analyzed, and an initial velocity compensation method is proposed. Experimental results show that high-accuracy self-alignment can be achieved using the proposed method under the joint disturbance of angular and linear motions.