Model predictive control with output feedback for a deorbiting electrodynamic tether system

A study is devoted to the rapid and stable deorbit of an electrodynamic tether (EDT) system in an inclined orbit via the output feedback control of the electric current flowing in the EDT. The proposed controller is designed on a basis of the model predictive control (MPC) method so as to optimize the deorbiting performance while accounting for the system constraints and nonlinear dynamics. The orbital motions of the system are described using the modified equinoctial (ME) elements, which are nonsingular for all trajectories with inclination below 180 degrees instead of the classical Keplerian orbital elements.