Satellite Attitude Control System Parameters Optimization

Abstract

The design of the attitude control system (ACS) of satellites with flexible stluctures like panels and antennas as well as of the flexible robotic manipulators become difficult task as long as the dimensions of such structures increase and the decree of oointine is vem stnneent. This because the ACS needs to carry out many different space maneuvers and at the same time it has to damp out the assmiated residual vibration remaining to a level such the mission requirements can be performed. Examples of proiects that involve m a t flexible space stluctures are: the Hubble Space Telescope, the International Space Station (ISS) and the ROKVISS (Robotic Components Verification at the ISS), the former in development at Geerman Space Center (DLR) in cooperation with the Division of Space Mechanics and Control - DMC of the National Instituted for Space Research - INPE. In this paper one presents the results of a rigid-flexible satellite attitude control system design where parameters like the moment of inertia of the reaction wheel and the length of the panel are optimiled in order to improve the satellite ACS performance. The results of this investigation have given important information, which can be used in the beginning of the ACS design, like the size of the reaction wheel to be used, the level of panels vibntion tolerated to cmy out attitudes maneuvers keeping the stability and the static form of the flexible stlucture. The optunization of the these values and measures are extremely important in order to assure the control system good performance in different space mission phase when it is necessary the micro-gravity environment andlor a great degree of pointing accuracy