Design of External Damping Network and Discretization Algorithm for Long-endurance Inertial Navigation System

Shipborne strapdown inertial navigation system (SINS) need to ensure long-term navigation accuracy and reliability. When SINS is used for a long time, without the assistance of external information, due to the drift of the inertial devices, the navigation results show divergent characteristics after integral operation. Horizontal damping introduces a damping network in the Schuler cycle of the system, so that the Schuler periodic oscillation error is damped. Compared with Kalman integrated navigation, the damping navigation system has better long-term stability. Through reasonable parameter settings damping network can ensure that navigation results do not diverge for a long time. This paper firstly constructs the external horizontal damping network, and then introduces bilinear transformation to derive the discretization damping method in detail. Simulation results show that the discretization damping network can ensure the reliable positioning accuracy during the long-term operation of the system, which proves that the damping network and the discretization method have broad application prospects.