October 17, 2023, Tuesday, 03:00PM (GMT+03.00, Moscow)

Abstract:

The problem of controlling the relative translational and angular motion of a group of small satellites in low Earth orbit using the aerodynamic drag is considered. The study analyzes the problem of controlling the motion of a large number of small satellites and the problem of constructing formation flying of three satellites in a configuration of a regular triangle with a varying side length. For the former problem, decentralized control algorithms, which take into account communication restrictions, are proposed to eliminate relative drift and to achieve bounded motion. An analytical study of controlled motion using graph theory has been carried out, the results of which are compared with the results of a numerical study. For the latter problem, a PD controller-based algorithm has been developed to ensure the required change in satellite latitude arguments. Motion of triangle formation was studied taking into account the second zonal harmonic of the Earth, the inaccuracy of knowledge of the atmosphere density and launching errors. To implement the required control using aerodynamic drag, the work considers the satellites equipped with a three-axis magnetic attitude control system. A methodology is proposed for finding the parameters of the attitude control algorithm to ensure the asymptotic stability of the gravity gradient equilibrium points for dynamically extended small satellite. Attitude accuracy was studied numerically taking into account errors in knowledge of the inertia moments and the Earth's magnetic field.