Robust adaptive control. Design, analysis and robustness bounds

Abstract

Despite the publication of numerous papers and several books dealing with the design, analysis and robustness properties of adaptive control, the theory of adaptive control may appear too technical and sometimes confussing to some people due to the so many different approaches, modifications and stability tools employed by various researchers in the field. The effort of this paper is to alleviate some of this confusion by presenting a procedure for designing and analyzing adaptive schemes. This procedure not only unifies most of the modifications used for stability and robustness but also clarifies why different approaches lead to the same result. The general framework that we developed can be used not only to analyze and unify most of the adaptive control schemes proposed in the literature but also to generate new ones. In additions, the analytical tools used allow the calculation of robustness margins and error bounds in a straightforward manner.