SINS initial alignment method using robust filtering for Towed Ocean Bottom Magnetometer

The Hinfin filtering optimization method is adapted to the initial alignment of Strap-down Inertial Navigation System (SINS), which is one of the key technologies for Towed Ocean Bottom Magnetometer (TOBM) to achieve high-resolution non-magnetic heading navigation. Compared with the standard Kalman filter, Hinfin filtering filter is more robustness and also improves the accuracy. The application of observability analysis can solve the contradiction between the misalignment angles´s convergence speed and alignment accuracy effectively. The simulation results show that, Hinfin robust filtering is a very effective estimation method and can become a reference plan for deep-sea accurate positioning.