Design of a controller for a rigid-flexible satellite using the H-infinity method considering the parametric uncertainty

In the design of the Attitude Control System (ACS) for a Rigid-flexible Satellite (RFS) it is important to take into account the influence of the structure's flexibility, since its interaction with the satellite rigid motion during translational and/or rotational maneuver, can damage the ACS pointing accuracy. In the linearization and/or reduction of the RFS mathematic model, usually one loses some important information associated with the satellite true dynamical behavior. One way to recovery this information is to include in the ACS design the parametric and non parametric uncertainties of the system. The H infinity control methodology is able to take into account the parametric uncertainty in the control law design so as the controller becomes more robust. This paper presents the design of a robust controller using the H infinity control technique to control the attitude of a RFS which is represented by a flexible beam connected to a central rigid hub considering the set of parametric uncertainty. The results of the simulations have shown that the control law designed with the H-infinity control method was robust enough to support the action of uncertainties and control the RFS attitude and suppress its panel's vibrations.