Abstract: To address the attitude control problem for high-speed morphing vehicles (HMVs) under strong coupling, parameter perturbations, and multi-source disturbances, this paper proposes a prescribed performance super-twisting sliding mode control (PPC-STSMC) method based on high-order fully actuated system (HOFAS) modeling. Firstly, a high-order attitude dynamics model of the vehicle is established using the HOFAS approach. Through an order-augmentation and term-elimination process, the unmodeled dynamics caused by aerodynamic/structural coupling are attenuated. The nonlinear dynamic equations are transformed into the HOFAS form, and by employing a parametric design for the characteristic polynomial's coefficient matrix, the decoupling of state variables and separation of control are achieved. Secondly, to handle the lumped uncertainties arising from time-varying aerodynamic parameters during morphing and external disturbances, while also considering the dynamic response characteristics of the actuators, a PPC-based super-twisting sliding mode controller is designed. By constructing time-varying performance boundary functions and robustly constraining attitude control errors. The asymptotic stability of the system is proven using a Lyapunov function. Finally, the performance of the proposed attitude controller is verified through Model-in-the-Loop (MIL) simulations and Hardware-in-the-Loop (HIL) experiments. The results demonstrate that the proposed method significantly reduces control chattering and validate its real-time performance and engineering practicability on an embedded platform.

Key words: high-speed morphing vehicle, high-order fully-actuated system, prescribed performance control, super-twisting sliding mode control, model-in-the-loop, hardware-in-the-loop