Chapter 7 - Improved mixed H2/H∞ control with poles assignment constraint

Abstract

In this chapter, a novel improved mixed H2/H∞ control technique combined with poles assignment theory is presented to achieve attitude stabilization and vibration suppression simultaneously for flexible spacecraft. The flexible spacecraft dynamics system is described and transformed into corresponding state-space form. Based on LMIs scheme and poles assignment theory, the improved mixed H2/H∞ controller does not restrict the equivalence of the two Lyapunov variables involved in H2 and H∞ performance, which can reduce conservatives compared with traditional mixed H2/H∞ controller. Moreover, it can eliminate the coupling of Lyapunov matrix variables and system matrices by introducing a slack variable that provides an additional degree of freedom. Several simulations were performed to demonstrate the effectiveness and feasibility of the proposed method in this chapter.