Using delays and time-varying gains to improve the static output feedback stabilizability of linear systems A comparison
Résumé
We address the output feedback stabilization problem of linear finite-dimensional SISO systems. Limitations of static time-invariant output feedback on stabilizability are well known. We investigate and compare the possibilities of two recently proposed simple modifications/generalizations of static time-invariant output feedback to remove such limitations. The first approach consists of introducing a time-delay in the control law, which can be treated as an additional control parameter. The second approach consists of making the gain time-varying. We show that both approaches are complementary. Existing theoretical results are brought together in a unifying framework. Numerical procedures for the construction of the controllers are provided. Robustness w.r.t, both parametric and delay uncertainty are dealt with. As an illustration the stabilizability of all second-order systems is completely determined. © Institute of Mathematics and its Applications 2004; all rights reserved.