LOW-AND-HIGH GAIN DESIGN TECHNIQUE FOR LINEAR-SYSTEMS SUBJECT TO INPUT SATURATION - A DIRECT METHOD

The low-and-high gain design technique, which was initiated for a chai n of integrators and completed for general linear asymptotically null controllable with bounded controls systems, was conceived for semiglob al control problems beyond stabilization and was related to the perfor mance issues such as semi-global stabilization with enhanced utilizati on of the available control capacity and semi-global disturbance rejec tion. Although the low-and-high gain design technique, as initiated fo r a chain of integrators, is based on an explicit eigenstructure assig nment algorithm, its full development is based on the solution of an a lgebraic Riccati equation (ARE) which is paramterized in an arbitraril y small scalar, called low gain, parameter. In this paper, we develop a new complete low-and-high gain design procedure which is based on an explicit eigenstructure assignment algorithm. The new design approach avoids the solution of the numerically stiff parametrized ARE. (C) 19 97 by John Wiley & Sons, Ltd.