Multiple adaptive models for control

It was recently shown by the authors that if it is known a priori that the unknown plant parameter vector lies in the convex hull of a set of adaptive model parameter vectors at the initial time, it will remain in the convex hull of the parameters even as they evolve with time. This result, which was derived earlier for the case when the state vector of the plant can be measured, is extended in this paper to the case when only the input and the output of the plant are accessible. This information, in turn, is used to describe different stable strategies for controlling the adaptive system.