Investigation of Enhanced Inertial Navigation Algorithms by Functional Iteration

The defects of the traditional strapdown inertial navigation algorithms become well acknowledged and the enhanced traditional algorithms have been quite recently proposed trying to mitigate both theoretical and algorithmic defects. In this paper, the analytical accuracy evaluation of both the traditional algorithms and the enhanced algorithms is investigated, against the true reference for the first time enabled by the functional iteration approach having provable convergence. The analyses by the help of MATLAB Symbolic Toolbox show that the resultant error orders of all algorithms under investigation are consistent with those in the existing literatures, and yet the effect of the enhanced algorithms is marginal. Numerical results agree with analyses that the enhanced algorithms have marginal accuracy improvement over the traditional algorithms, while the functional iteration approach possesses significant accuracy superiority even in sustained lowly dynamic conditions.