A Novel SINS/CNS Integrated Navigation Scheme Using Rodrigues Parameters

In the strapdown inertial navigation system (SINS)/celestial navigation system (CNS) integrated navigation system, the mathematical platform angular error is used as the measurement for the information fusion process. In practical applications, however, only the attitude angular error of SINS and CNS can be obtained. In this article, the transformation relationship between the attitude angular error described by Rodrigues parameters (RPs) and the mathematical platform angular error in the launch inertial coordinate system is derived. Based on the transformation relationship, a novel SINS/CNS integrated navigation scheme is established. Besides, to deal with the information fusion problem under unknown measurement noise statistic, we develop a beta-parameterized variational Bayesian Kalman filter (BPVBKF), which can demonstrate better robustness against noise uncertainty and weaker sensitivity against parameter initialization. Simulation results validate the effectiveness of the novel integrated navigation scheme and the novel information fusion algorithm.