A new inclination cranking method for a flexible spinning solar sail

The attitude and orbit motion of a spinning solar sail containing a huge membrane is discussed. Solar sail is a feasible option to attain high-inclination heliocentric orbit through an inclination cranking maneuver. This paper investigates the strategies of station keeping and slew maneuver during the inclination cranking in the presence of membrane oscillation. Utilizing the dynamical characteristics of a spinning solar sail, the station keeping is achieved passively by designing the spin rate and the offset between the center of mass and center of pressure. The required attitude is designed to be the equilibrium of the system, and it is proved that the equilibrium is marginally stable. The slew maneuver is achieved using extra control input torques. The pitch angle between the sunlight and sail normal is set constant to plan a reference path for the slew maneuver. Then, a sliding mode control method is used to design the control law to track the reference path. The system is asymptotically stabilized in the presence of the membrane oscillation. Numerical simulations using the full orbit-attitude-oscillation dynamical equations validate the stability of station keeping and slew maneuver.