Stable gain-scheduling on endogenous signals

Gain-scheduling is possibly the most widely used nonlinear control design technique in industry. However, guaranteeing the stability of the nonlinear closed loop can be extremely challenging, specifically for endogenously scheduled controllers. Given a set of locally linear models and previously designed controllers, this paper addresses the problem of 1) guaranteeing internal stability of the nonlinear closed loop, and 2) determining the class of disturbances and reference changes that can be stably endured, despite arbitrarily fast changes in the scheduling parameter. A simple example illustrates the approach.