Attitude maneuvers of satellite with variable shape functions using invariant manifold-based feedback/switching control

• Satellite attitude maneuvering is studied using a novel Variable Shape Attitude Control (VSAC) method. • A four-paddle actuation system uses an invariant manifold-based feedback/switching control law for maneuvers. • Simulations validate the invariant manifold-based switching control law to accurately estimate settling time. Variable shape attitude control (VSAC) is a novel spacecraft attitude control method. Heuristic and machine learning-based controllers have been proposed to address the attitude maneuvering problem. However, these schemes cannot predetermine the settling time for attitude maneuvers analytically. Accurate time management is imperative for space mission success; hence, the settling time required for attitude maneuvers must be precisely predetermined. This study proposes a novel control algorithm based on a repeated four-paddle motion. This algorithm integrates an invariant manifold-based control law and the coning effect to achieve large-angle attitude maneuvers with respect to an indirect control axis. A spherical triangle geometry is considered to attain tri-axial attitude maneuvers. This geometry is used to derive the relationship between the angle of the main body about the symmetric axes with respect to the two pairs of paddle rotation axes and the necessary maneuver angles of the main body about the axes, where the motion of a pair of paddles can directly generate maneuver torque. In numerical simulations, the proposed method proved to be effective in the attitude control of VSAC satellites and accurate estimation of settling time, even for tri-axial maneuvers.