Gain scheduling using the Youla parameterization

Gain scheduling controllers are considered in this paper. The gain scheduling problem where the scheduling parameter vector θ cannot be measured directly, but needs to be estimated, is considered. An estimation of θ has been derived by using the Youla parametrization. The use of the Youla parameterization in connection with the estimation of θ gives a direct validation method for the estimate of θ. The validation is an integrated part of the estimation method. This makes it possible to estimate θ very precisely. This is important in connection with ℋ_∞ gain scheduling controllers