A robust constrained control approach for flexible air‐breathing hypersonic vehicles

• Published in: International journal of robust and nonlinear control Vol. 30; no. 7; pp. 2752 - 2776
• Main Authors: Bu, Xiangwei, Wei, Daozhi, He, Guangjun
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 10.05.2020; Wiley Subscription Services, Inc
• Subjects: Actuators; Adaptive control; Aerodynamic coefficients; Attenuation; back‐stepping; Constraints; control input constraints; Control stability; Control systems design; Control theory; Controllers; Disturbance observers; dynamic surface control; Feedback control; flexible air‐breathing hypersonic vehicle (FAHV); Hypersonic vehicles; nonlinear disturbance observer (NDO); parametric uncertainties; Robust control; Stability analysis; Uncertainty
• ISSN: 1049-8923; 1099-1239
• DOI: 10.1002/rnc.4912

This article investigates the robust adaptive control system design for the longitudinal dynamics of a flexible air‐breathing hypersonic vehicle (FAHV) subject to parametric uncertainties and control input constraints. A combination of back‐stepping and nonlinear disturbance observer (NDO) is utilized for exploiting an adaptive output‐feedback controller to provide robust tracking of velocity and altitude reference trajectories in the presence of flexible effects and system uncertainties. The dynamic surface control is introduced to solve the problem of “explosion of terms.” A new NDO is developed to guarantee the proposed controller's disturbance attenuation ability and to performance robustness against uncertain aerodynamic coefficients. To deal with the problem of actuator saturation, a novel auxiliary system is exploited to compensate the desired control laws. The stability of the presented NDO and controller is analyzed. Simulation results are given to demonstrate the effectiveness of the presented control strategy.