Robust Filter Method for SINS/DVL/USBL Tight Integrated Navigation System

In order to solve the problem of strap-down inertial navigation system (SINS)/Doppler velocity log (DVL)/ultrashort baseline (USBL) system interference in complex underwater environment, an asynchronous sequential robust filter method is proposed in this article. The USBL original information of azimuth, slant range and altitude are introduced as the measurement information. The problem of large amount of computation caused by the high measurement dimension of multisensor information fusion is solved by introducing asynchronous sequential filter technology. Meanwhile, a robust Kalman filter (KF) algorithm is proposed, which is based on the Mahalanobis distance. The outlier detection is designed based on statistical characteristics. Finally, the effectiveness of the method proposed in this article is verified by simulation and River experiments. The experimental results show that the method proposed in this article can effectively eliminate outliers and improve the navigation accuracy while reducing the amount of computation.