Design and Robustness Evaluation of a Flight Control System for Hypersonic Flight Experiment Vehicle

Abstract

This paper describes design of a flight control system for the hypersonic flight experiment vehicle (HYFLEX) and evaluation of robustness against variations of command inputs. A nonlinear simulation model is made using the data obtained from wind tunnel experiment, etc. Linear models are computed from the nonlinear model at every second of the flight, assuming that the flight is quasi-equilibrium flight. A nominal model for controller design is made from the linear models. The type-1 LQ servo controller is employed for the controller. Six sets of control gains are computed and scheduled as a function of flight time. The effectiveness and robustness are examined through computer simulation.