Research on Internal Damping Algorithm of Marine Inertial Navigation System

Due to the gyro random walk and other reasons, Schuler oscillation amplitude of undamped inertial navigation system will increase with time. The marine inertial navigation systems were often required to work continuously for hours to days or even longer, over divergent INS position error will cause loss of navigation function. Thus, the appropriate algorithm in the system must be added to damp the Schuler oscillations. The damping networks for INS level channels are designed. For the applications of marine INS, a new internal damping method which uses its own measurements as reference velocity rather than external inputs is presented. Marine test results show that the proposed internal damping method can suppress the Inertial Navigation System Schuler oscillation error and make it no longer divergent, thereby improving the navigation accuracy of INS in long-endurance applications, and has practical values in engineering.