Design of an Initial Fine Alignment Algorithm for Satellite Launch Vehicles

  • Song, Eun-Jung (Korea Aerospace Research Institute) ;
  • Roh, Woong-Rae (KSLV Reseach & Development Head Office, Korea Aerospace Research Institute) ;
  • Kim, Jeong-Yong (KSLV Reseach & Development Head Office, Korea Aerospace Research Institute) ;
  • Oh, Jun-Seok (KSLV Reseach & Development Head Office, Korea Aerospace Research Institute) ;
  • Park, Jung-Ju (KSLV Reseach & Development Head Office, Korea Aerospace Research Institute) ;
  • Cho, Gwang-Rae (KSLV Reseach & Development Head Office, Korea Aerospace Research Institute)
  • Published : 2010.09.15


In this paper, an initial fine alignment algorithm, which is developed for the strap-down inertial navigation systems of satellite launch vehicles, is considered. For fast and accurate alignment, a simple closed-loop estimation algorithm using a proportional-integral controller is introduced. Through computer simulation for the sway condition in the launch pad, it is shown that a simple filter structure can guarantee fast computational speed that is adequate for real-time implementation as well as the required alignment accuracy and robustness. In addition, its implementation results are presented for the Naro-1 flight test.



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