Multi Inertial Navigation System Fusion Method Considering Ship Deformation

Affected by the ship deformation, the navigation accuracy of multi inertial navigation system fusion will suffer degradation. In order to solve the problem, a fusion method considering ship deformation based on inertial vector matching and rotation incentives is proposed. The inertial vector matching method takes the difference of angular velocities and specific forces between two INSs as the measurement to estimate the ship flexure. However, the traditional method can only estimate the difference of the two INSs biases, but cannot estimate the respective biases themselves. By designing different rotation schemes, the two INSs gyroscope and accelerometer sensitive axes orientation are different in each rotation modulation period. In this way, the respective biases can be incentivized and estimated through the Kalman filter. The simulation results demonstrate that the proposed fusion method can effectively estimate the respective horizontal biases and reduce the ship flexure estimation error.