LOW-THRUST INCLINATION CONTROL IN PRESENCE OF EARTH SHADOW

The problem of inclination change in near-circular orbit using intermi ttent, low thrust solar electric propulsion is analyzed. Given the sha dow are length and the line of nodes of initial to final orbits, piece wise constant yaw angles are selected, and the location along the orbi t where the yaw angle switches is optimized to carry out the largest i nclination change per revolution for that particular geometry. Single- switch and two-switch strategics are analyzed, and several algorithms of varying complexity are described and numerically tested for their r elative performance. This approach yields suboptimal but robust and re al-time autonomous onboard guidance software for electric orbit transf er vehicle orbital transfer applications.