Design of Sliding Mode Tracking Control for Hypersonic Reentry Vehicles

An integral sliding mode controller is designed via equivalent approach under model uncertainties and external disturbances to provide robust, de-coupled tracking of the guided angle command for hypersonic reentry vehicles. All uncertainties and disturbances are not required to be constants. They may be bounded by some known functions of states and external measurable variables. In the presence of uncertainties and disturbances, the designed integral sliding surface provides the bounded tracking error and the sliding mode controller ensures that the system approaches the sliding surface with high speed and reaches it in a finite time. Finally, the tracking of the guided angle command for a nominal trajectory of a reentry vehicle is simulated as an example. Simulation results demonstrate that the designed controller has robust de-coupled tracking performance.