Tailored Dynamic Gain-Scheduled Control

This paper advances the theoretical basis and application of dynamic gain-scheduled control, a novel method for the control of nonlinear systems, to an aircraft model. Extensions of this method involving multivariable gain scheduling and continuation tailoring are developed. The idea behind this method is to schedule the control law gains with a fast-varying state rather than with a slow-varying state or an input parameter. This approach is advantageous because it is then possible to schedule the gains with a state that is dominant in the mode that we are most interested in controlling. The use of this type of gain scheduling is shown to improve the transient response of the aircraft model when stepping between trim conditions and to reduce control surface movement, thus reducing the potential for saturation problems. Hidden coupling terms that introduce unwanted dynamics when scheduling gains with a fast state (rather than the input design parameter) are eliminated directly by applying a transformation to the classical parameter-scheduled gain distributions that are calculated using optimal control theory. A highly nonlinear unmanned combat air vehicle model is used to demonstrate the design process.