Academic Editor: Victor S. Kozyakin
Copyright © 2012 Huxiong Li. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
The tracking problem for continuous-time systems is investigated. It is assumed that the states
of the systems are not available. An observer is firstly designed to estimate the states by using the method.
The control action is consist of a state-feedback control, an integral component, and a feedforward loop. The
linear-matrix-inequality region is used to constrain the eigenvalue location for the closed-loop systems. The control
gains can be obtained by solving a sequence of linear matrix inequalities (LMIs) which can guarantee the mixed
performance for the closed-loop systems.