Compound control of an uncertain hypersonic vehicle model

Abstract

The extremely broad flight envelope brings remarkable uncertainties to hypersonic vehicles. This paper investigates the longitudinal control problem of hypersonic vehicles with synthetical considerations on multiple modelling uncertainties, especially on time-varying aerodynamic coefficients. To overcome the efficiency loss of aerodynamic control surfaces (ACS), the reaction control system (RCS) is employed to assist the attitude control. An adaptive ACS-RCS compound control is proposed, which deals with uncertain RCS parameters, simultaneously. Other factors including scramjet input saturation, variable geometry inlet, external disturbances and structural flexibilities are also taken into account. Analysis and simulation indicate that preset references can be well tracked with prescribed performances.