Abstract
To reduce the impact of offshore launching platform motion and swaying on the self-alignment accuracy of a launch vehicle, a rapid self-alignment strategy, which involves an optimal combination of anti-swaying coarse alignment (ASCA), backtracking navigation, and reverse Kalman filtering is proposed. During the entire alignment process, the data provided by the strapdown inertial navigation system (SINS) are stored and then applied to forward and backtrack self-alignment. This work elaborates the basic principles of coarse alignment and then analyzes the influence of ASCA time on alignment accuracy. An error model was built for the reverse fine alignment system. The coarse alignment was carried out based on the above work, then the state of the alignment system was retraced using the reverse inertial navigation solution and reverse Kalman filtering with the proposed strategy. A cycle-index control function was designed to approximate strict backtracking navigation. Finally, the attitude error was compensated for after the completion of the first and the last forward navigation. To demonstrate the effectiveness of the proposed strategy, numerical simulations were carried out in a scenario of launch vehicle motion and swaying. The proposed strategy can maximize the utilization of SINS data and hence improve the alignment accuracy and further reduce the alignment time. The results show that the fully autonomous alignment technology of the SINS can replace the complex optical aiming system and realize the determination of the initial attitude of a launch vehicle before launch.
Funder
Fourth Batch of Pre-research on Manned Spaceflight
Subject
Electrical and Electronic Engineering,Biochemistry,Instrumentation,Atomic and Molecular Physics, and Optics,Analytical Chemistry
Reference30 articles.
1. Fu, M.Y., Zheng, X., and Deng, Z.H. (2016). Transfer Alignment Theory and Applications, Science Press. [1st ed.].
2. Anti-Swaying Self-Alignment Method Based on Observation Vector Inertia for SINS under Latitude Uncertainty;Zhang;Measurement,2021
3. Wang, S.Y., Zhang, Q., and Guo, T. (2022, October 01). Research on the Application of Adaptive Transfer Alignment Technology in the Initial Alignment on an Offshore Launching Platform. China CIO News. Available online: https://qikan.cqvip.com/Qikan/Article/ReadIndex?id=7105510250&info=eUjW%2fnPsSZYKMRAjEt0qYn1ByP74B25tKphQ%2f9urBA6BiRRTmRl1gA%3d%3d.
4. Odometer Aided SINS in-Motion Alignment Method Based on Backtracking Scheme for Large Misalignment Angles;Wen;IEEE Access,2020
5. Error Analysis of Analytical Coarse Alignment Formulations for Stationary SINS;Silva;IEEE Trans. Aerosp. Electron. Syst.,2016