Abstract
In this paper, an attempt to control a real system by changing LQ control laws corresponding to its operation regions is reported. The system to be considered has nonlinear characteristics and is described by an inaccurate mathematical model. To develop the control scheme, the method of multi-sectional control is presented and discussions are given on the robust stability of the original real system, which is described by a first-order differential equation. The proposed method has been applied to the control of a simple hovercraft model which has nonlinear characteristics ; then the effectiveness of the method is demonstrated through several elevation control experiments.
