Application of quaternion estimator algorithm dedicated on alignment of swaying and moving carrier

An optimal attitude estimation method with Quaternion Estimator based on gravity vectors is developed to solve the initial alignment problem of the inertial navigation system in swaying and moving carrier. Based on the traditional initial alignment method with gravity vectors, the process of solving the direction cosine matrix is converted to Wahba problem, which can make full use of the gravity vector information and realize the optimal algorithm for the coarse alignment of the swaying basement by Quaternion Estimator algorithm. Simulation and lake experiments demonstrate that the modified method can significantly increase the precision and rapidity of the attitude estimation and the precision of the heading alignment on a swaying and moving carrier. The precision can be increased by one order of magnitude on the carrier with periodically linear movement, and the overall velocity precision can be increased by 50%.