Document Type : Original Article

Authors

Faculty of Electrical & Computer Engineering, Malek Ashtar University of Technology, Tehran, Iran.

10.22034/jast.2022.327899.1113

Abstract

In this study, terminal phase guidance of a vertical-landing booster has been considered. At first, dynamical equations have been derived assuming variable mass, density and gravity model. Then by considering these parameters as constants, sensitivity variables have been extracted using the vectorized high order expansions method. By using these sensitivity variables, a guidance law for updating optimal path and commands has been given. By implementing this guidance law, and considering initial deviations, near optimal path and guidance command have been extracted online, and the performance has been studied by means of simulations. To this end, intrinsic errors of the theory has been considered and confirmed at first. Then, a set of simulations considering variable mass, density and gravity have been implemented and the performance of the method has been evaluated in the presence of a vast variety of initial deviations. By investigating the results, which have been presented as graphs and numerical errors it can be seen that the landing errors are small and for booster landing mission, the vectorized high order method shows remarkable performance.

Keywords

Main Subjects

Article Title [فارسی]

Adaptable Nonlinear Guidance Law Design with Respect to Initial Deviation for Booster Vertical Landing Mission

Authors [فارسی]

  • Morteza Sharafi
  • Nasser Rahbar
  • Ali Moharrampour
  • Abdorreza Kashaninia

Faculty of Electrical & Computer Engineering, Malek Ashtar University of Technology, Tehran, Iran.

Abstract [فارسی]

In this study, terminal phase guidance of a vertical-landing booster has been considered. At first, dynamical equations have been derived assuming variable mass, density and gravity model. Then by considering these parameters as constants, sensitivity variables have been extracted using the vectorized high order expansions method. By using these sensitivity variables, a guidance law for updating optimal path and commands has been given. By implementing this guidance law, and considering initial deviations, near optimal path and guidance command have been extracted online, and the performance has been studied by means of simulations. To this end, intrinsic errors of the theory has been considered and confirmed at first. Then, a set of simulations considering variable mass, density and gravity have been implemented and the performance of the method has been evaluated in the presence of a vast variety of initial deviations. By investigating the results, which have been presented as graphs and numerical errors it can be seen that the landing errors are small and for booster landing mission, the vectorized high order method shows remarkable performance.

Keywords [فارسی]

  • Vectorized High Order Expansions
  • Optimal control
  • Booster Landing
  • High Order Expansions