Predefined-Time Control for Nonplanar Hexarotor UAVs Based on High-Order Fully Actuated System Theory

This paper focuses on a nonplanar fully actuated hexacopter UAV, addressing the issues of sudden mass changes and external disturbances during flight by proposing a robust control strategy based on predefined-time control. Firstly, a dynamic model of high-order fully actuated hexacopter incorporating mass variation characteristics and external disturbances is established. Secondly, by integrating high-older fully actuated system theory with sliding mode control methodology and incorporating predefined-time control theory, a sliding mode controller with strict temporal constraints was designed. This controller achieves robust control against mass variations and disturbance upper bounds, ensuring that the system states converge to zero within a user-specified predefined-time and maintain stability thereafter. Simulation results demonstrate that the proposed method exhibits excellent predefined-time convergence in disturbance environments and trajectory tracking accuracy.