Optimal Control for Lunar Vehicle Manouver to the Selected Soft Landing Point Between Hoverings
Dynamics, ballistics, movement control of flying vehicles
Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia
This work deals with the problem of lunar lander flight optimal control for soft landing at the sel ected point of the Moon, using the «hovering» scheme after the main deceleration step. The method of thrust vector control program selection for landing phases between hoverings, providing zero velocity and vertical orientation at the beginning and the end of this step is given.
The aim of this work is to provide a method of traction control problem approximate solution at the stage of controlled landing, satisfying all the given boundary conditions. Essentially, the optimality criterion is considered as the amount of required fuel for the controlled landing, which should be minimized.
Formulation and solution of the problem, resulting in this work, differs fr om formulation and solution, obtained in traditional papers. It is the difference, which at the beginning and the end of controlled landing ensures vertical orientation, zero speed and coordinates of lunar lander.
To achieve this goal a flight movement model of lunar lander was developed, an optimal control problem was formulated, simplifying assumptions were introduced, the methods for solving the boundary value problem in conjunction with optimization, using computational algorithm and program solutions, were formed. The results of a numerical computation example are presented.The main result is a method of selection the angle pitch and engine thrust control program for the lunar lander between hoverings, providing zero velocity and vertical orientation for the lunar lander at the beginning and the end of this controlled landing step.
Keywords:lunar lander, soft landing, hovering, optimal control
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