The three-axis model of spacecraft fitted with flexible solar panels and a rotating RF (Radio-Frequency) antenna is derived. This model is fully parametrized according to the uncertain dynamic parameters (mass, centering, inertia, flexible mode frequencies) and varying parameters (solar array angular configuration, RF antenna rotating rate). A robust three-axis attitude controller is then designed to reject orbital disturbances. A pointing error budget is then performed to assessn the effects of the disturbances coming from the Solar Arra yDriving Mechanism( SADM) and the time-periodic disturbance coming from the rotating RF antenna.