Design of decentralized robust attitude controller for hypersonic sliding vehicles

Based on the mission and aerodynamic features of hypersonic sliding vehicles, the control-oriented model was built by taking first-order actuator dynamics into account. The decentralized robust attitude controller for re-entry flight incorporated the idea of decentralized control and sliding mode control was designed. And the decentralized robust sliding surfaces were designed using Tornambe control technique to ensure good tracking performance in sliding mode in the presence of coupling and unmatched uncertainties. The second order sliding mode control law was synthesized using modified sub-optimal control method in which the on-line estimate of equivalent control reduced chattering. Finally, a six-degree-of-freedom simulation in Simulink for a conceptual hypersonic sliding vehicle was performed, the robust tracking of guidance command is guaranteed despite of large parameter perturbations.