Optimizing the process of changing spacecraft orbital parameters by using a spinning electrodynamic tether sytem

Abstract

The paper considers parametric optimization of the process of changing orbital parameters by using a spinning electrodynamic tether system. Changes in the semi-major axis and eccentricity are taken as the two major goals, and two control laws are proposed accordingly. Current is regulated according to the instantaneous position of the conductive tether, which allows ensuring the calculated direction of the Lorentz force produced by the interaction of the conductive tether with the Earths magnetic field. A combined control scheme for simultaneous changes in the semi-major axis and eccentricity is proposed. The parameters of control laws are optimized on the basis of the Nelder-Mead method by using different objective functions and constraints. It is also shown that, by using the criteria of quick response and minimum impulse, we obtain optimal solutions corresponding to the boundary values of the selected parameters. Therefore, a convolution of these criteria is proposed as a compromise, which ensures a specified change in the orbital parameters of the system mass center.

Keywords

• spinning electrodynamic tether system
• changing of orbital parameters
• semi-major axis
• misalignment
• fast response criterion
• minimum impulse criterion
• parametric optimization
• objective function