Capacity Statement: Not applicable. Conflicts of Interest: The authors declare no conflict of interest.
applied sciencesArticlePolar Region Integrated 5-Hydroxyferulic acid Protocol navigation Method Based on Covariance TransformationYongjian Zhang, Lin Wang , Guo Wei and Chunfeng GaoCollege of Sophisticated Interdisciplinary Studies, National University of Defense Technology, Changsha 410073, China; [email protected] (Y.Z.); [email protected] (G.W.); [email protected] (C.G.) Correspondence: [email protected]: Aircraft flying the trans-arctic routes typically apply inertial navigation mechanization in two diverse navigation frames, e.g., the neighborhood geographic frame plus the grid frame. Nonetheless, this modify of navigation frame will result in filter overshoot and error discontinuity. To resolve this challenge, taking the inertial navigation system/global navigation satellite method (INS/GNSS) integrated navigation program as an instance, an integrated navigation technique primarily based on covariance transformation is proposed. The partnership in the technique error state between different navigation frames is deduced as a means to accurately convert the Kalman filter’s covariance matrix. The experiment and semi-physical simulation results show that the presented covariance transformation algorithm can correctly resolve the filter overshoot and error discontinuity triggered by the modify of navigation frame. Compared with non-covariance transformation, the technique state error is thereby lowered significantly. Keywords: covariance transformation; integrated navigation; polar regionCitation: Zhang, Y.; Wang, L.; Wei, G.; Gao, C. Polar Region Integrated Navigation Method Primarily based on Covariance Transformation. Appl. Sci. 2021, 11, 9572. https://doi.org/ ten.3390/app11209572 Academic Editors: Kamil Krasuski and Damian Wierzbicki Received: eight June 2021 Accepted: 12 October 2021 Published: 14 October1. Introduction Contemplating that the distance of a great circle flight route is shorter, using trans-arctic routes can accomplish terrific savings in flying time when aircraft make transcontinental flights. Due to the demands of flight safety, each and every aircraft ordinarily uses an INS/GNSS integrated navigation technique to supply high-precision navigation info. The INS/GNSS integrated navigation program has broad improvement prospects. Previous literature [1] proposed an integrated navigation scheme primarily based on INS and GNSS single-frequency precision point positioning, which is anticipated to become an advantage for low-cost precise land automobile navigation applications. A number of researchers [2,3] have discussed the application of GNSS/INS on railways. Traditional INS/GNSS-integrated navigation algorithms are based on a north-oriented geographic frame. Nonetheless, because the latitude increases, the conventional algorithms drop their efficacy within the polar region due to the meridian convergence. To solve this issue, when the aircraft is inside the polar region, pilots normally plan their route based on polar-adaptable coordinate frames, for example the Earth-centered Earth-fixed frame (e-frame) [4], transversal Earth frame (t-frame) [5,6], pseudo-Earth frame [7], wander frame [8] and grid frame (G-frame) [9,10]. Despite the fact that these coordinate frames are adaptable to polar regions, they cannot achieve prosperous worldwide navigation individually mainly because some of them have certain mathematical singularities, including the t-frame, pseudo-Earth frame, wander frame, and G-frame. These coordinate frames are usually adopted only within the polar reg.
