Dynamic analysis and motion control of spinning tether system during its Earth to Mars flight

The dynamic analysis and motion control of a spinning tether system for an interplanetary mission to Mars is considered. The space system consists of two spacecraft connected by a tether with thrusts to control its movement. The movements of the tether system in the sphere of action of the Earth, on the interplanetary trajectory and in the sphere of action of Mars are consistently analyzed. In near-Earth orbit, the transfer of the system into rotation with the help of jet engines installed on the end spacecrafts is considered. The spin of the system is used to create artificial gravity during the interplanetary flight. The tether system spins in the plane perpendicular to the plane of the orbital motion of the center of mass of the system. To describe spatial motion of the system, a mathematical model is used, in which the tether is represented as a set of material points with viscoelastic unilateral mechanical connections. When calculating the movement of the system, an approach based on the method of spheres of action is used. Spacecrafts are considered as material points. The level of gravity and spin of tether system is controlled by thrusters. The structure of the controller for controlling the angular speed of rotation of the tether system is proposed. The simulation results are presented to confirm the effectiveness of the proposed control algorithm, which provides a given level of artificial gravity for th e interplanetary mission under consideration.