Disturbance Observer-Based Antiwindup Control for Air-Breathing Hypersonic Vehicles

In this paper, a combination of feedback linearization and disturbance observer-based control (DOBC) is adopted for the design of a state-feedback controller that regulates the velocity and altitude of air-breathing hypersonic vehicles (AHVs) subject to constrained inputs. First, a disturbance observer is established to estimate the overall effect of possible uncertainties and disturbances on the nominal vehicle model which is called the lumped disturbance. Then, a compensation method is proposed based on disturbance observer and feedback linearization control to counteract the mismatched lumped disturbance. Furthermore, a novel antiwindup modification is implemented on the baseline control to handle the possible input saturation. The designed controller addresses the issue of stability robustness with respect to system uncertainties and disturbances, and achieves zero-error tracking with good performance and antiwindup property meanwhile, which is the major merit compared with other existing AHV controllers. Finally, simulation is presented to verify the effectiveness of this control scheme.