Systematic H-infinity weighting function selection and its application to the real-time control of a vertical take-off aircraft

In this paper, the selection of H-infinity weighting functions for general practical applications is investigated. It is shown that an H-infinity weig hting function for a single-input-single-output (SISO) plant can be obtaine d by considering a series of connections of elementary low-order plants. Fo r a constrained control effort, an explicit weighting function expression i s derived for the first time. A novel method for the selection of weighting functions in H-infinity mixed sensitivity design is proposed to control th e percentage overshoot directly. An example illustrating how the transient response of a standard H-infinity design is improved by using the proposed weighting functions is provided. Finally, real-time experimental results ar e presented for the roll-angle control of a laboratory-scale physical model of a vertical take-off aircraft. (C) 2000 Elsevier Science Ltd. All rights reserved.