Robust control for hypersonic vehicles with parametric and unstructured uncertainties

A robust flight controller is proposed for the longitudinal model of generic hypersonic vehicles, whose dynamics involves nonlinearities, parameter uncertainties, and unstructured uncertainties. The proposed longitudinal controller is developed based on the standard H theory and the robust compensating approach. The robust compensating approach is introduced to reduce the influences of multiple uncertainties and nonlinearities on the closed-loop control system. Compared to the H control theory, these influences in the whole frequency range can be restrained. Theoretical analysis and numerical simulation results are presented to illustrate the tracking performance properties of the designed robust control approach.