Novel control strategy for balancing resources and performance of constrained flexible hypersonic vehicles

This article aims to derive an anti-disturbance tracking control algorithm for flexible air-breathing hypersonic vehicles (FAHVs) with uncertain aerodynamic parameters, external disturbances, input saturation and limited transmission resources. Based on the framework of the backstepping technique, a novel event-triggered appointed-time fast tracking control protocol is proposed. Firstly, augmented sliding mode observers are used to provide the estimation of the lumped disturbances. Then, to guarantee satisfactory transient response and steady-state performance, the practical fixed-time controller and the appointedtime prescribed performance controller are designed. In addition, to address the problem of actuator saturation, the auxiliary system and the saturation approximate function are introduced. Finally, two event-triggered mechanisms are applied to exactly determine when control signals should be updated, which naturally eliminate unnecessary waste of transmission resources. Our proposed method not only reduces the execution frequency of the actuator, but also further optimizes the transient and steady-state performance. The proposed control scheme achieves a balance between reducing communication frequency and improving the closed-loop system performance. The feasibility and the effectiveness of the proposed strategy is validate through simulations.