Controlling the rotation of a spacecraft by means of solar radiation pressure forces.


V.V.Beletsky, A.V.Grushevsky, E.L.Starostin.
J. Comput. Syst. Sci. Int., 1994, 32, No.3, pp. 70-76; translation from Izv. Ross. Akad. Nauk, Tekh. Kibern. 1993, No.1, 32-38, ISSN 1064-2307.

Abstract

Three-dimensional motion of the Small Space Lab (SSL) spacecraft about its centre of mass under the solar radiation torques is considered. The centre of mass of the spacecraft moves in a circular heliocentric orbit. The spacecraft has an axially symmetrical solar stabilizer and eight solar paddles arranged like a windmill. The paddle's slope angles are made controllable. In the design condition, the spacecraft fore-and-aft axis should be directed to the Sun and its spin rate should have a value required.

The equations in evolutionary variables are studied. The dynamical model takes into account an effect of re-radiating solar electromagnetic energy by the thin films of the stabilizer. A phenomenology model of re-radiation torque is suggested. It is shown, that the re-radiation torque leads to nutation damping.

An algorithm to control the solar paddles is developed. It provides bringing the spacecraft to the nominal Sun-pointing orientation with a given spin rate. The algorithm requires no synchronization with the spacecraft's spin rate and only the mean deviation of the fore-and-aft axis from the direction to the Sun has to be input. Thus, the algorithm may readily be implemented on board.

The results of numerical simulation are presented.


BACK

HOME