Continuous fixed-time sliding mode output feedback control for hypersonic vehicles

The fixed-time output tracking control (FTOFC) problem is investigated for a hypersonic vehicle(HV) in this article. Based on an input-output linearized model, a fixed-time extended state observer (FxTESO) is constructed to estimate the derivative and high-order derivatives of output tracking error and the external disturbances. Then, by using output tracking error and the estimations of its high-order derivatives, a continuous fixed-time sliding mode output feedback controller is constructed. The developed controller can guarantee system outputs converge to the reference signals in fixed-time. Finally, a simulation result is presented to demonstrate the effectiveness of the developed control scheme.