The design of predefined-time anti-saturation attitude control with disturbance observer for hypersonic morphing vehicles

Abstract This paper addresses the attitude control challenge of hypersonic morphing vehicles (HMVs) with uncertainties and actuator saturation. The primary contribution of this work lies in achieving a predefined settling time while ensuring robust control performance under morphing effects, actuator saturation and disturbances. Firstly, a control-oriented model is established based on the dynamics of HMVs. Subsequently, a nonsingular multivariable sliding mode manifold, utilising a switching function, is designed to attain predefined-time convergence and prevent singularity issues. A disturbance observer with an adaptive law is developed to precisely and swiftly estimate uncertainties and error states, while a predefined-time anti-saturation compensator is implemented to alleviate actuator saturation. Furthermore, closed-loop stability is guaranteed through rigorous Lyapunov synthesis. Extensive numerical simulations confirm the algorithm’s superiority in terms of control effectiveness.