The Geocentric Boost Optimization of a Spacecraft with a Solar Sail under Constraint on Sail Angular Velocity

The geocentric boost of SCSS with a flat solar sail, which is a mirror reflector on the both sides, under the constraint on the absolute value of a sail angular velocity is investigated. It is assumed, that the heliocentric orbit of the Earthis circular, a SC trajectory lies in the ecliptic plane, the sail is perpendicular to this plane. The following two sail control laws providing an effective increase of a SC total geocentric energy are investigated: 1) the locally optimal one modified with regard to the constraint on the sail angular velocity; 2)the optimal one derived from the solution of boundary-value problem of Pontrjagin maximum principle. In the second case, the functional is a SC total geocentric energy at the right end of the time interval considered, the sail angular velocity serves as control, optimal trajectory includes intermittent degenerate and nondegenerate parts. It is shown, that the most simply calculable, there is no need to solve a boundary-value problem, the locally optimal trajectory practically does not compare unfavorably with the optimal one in efficiency.