Comparison of the Satellite Attitude Control System Design using the H∞ Method and H∞/MLI with Pole Allocation Considering the Parametric Uncertainty

Abstract

This paper presents the comparison of the Attitude Control System (ACS) design for a rigid-flexible satellite with two vibrations mode, using the traditional H∞method and the H∞/LMI with pole allocation considering the parametric uncertainty. In the ACS design is important take into account the influence of thestructure’s flexibility, since they can interact with the satellite rigid motion, mainly, during translational and/or rotational manoeuvrer, damaging the ACS. Usually the mathematics model obtained from the linearization and/or reduction of the rigid flexible model loses information about the flexible dynamical behaviour and introduces some uncertainty. The satellite model is represented by a flexible beam connected to a central rigid hub considering a setof parametric uncertainties. Simulations results have shown that the control law designed by the H∞/LMI method has better performance and it is more robust than H∞method since the first was able to support the action of the uncertainty perturbation and to control the rigid flexible satellite attitude and suppressing vibrations.