Predefined-time trajectory tracking control for folding flapping wing air vehicles

This paper focuses on the trajectory tracking issue of folding flapping wing air vehicles (FFWAVs) with model uncertainties and external disturbances. A folding flapping wing model air vehicle is first established based on a detailed and systematic analysis of effects of aerodynamic forces and moments of FFMAVs caused by wing folding. Based on this model, a novel predefined-time control scheme is proposed. By establishing a novel predefined-time stability criterion, a control scheme combining PTASMDO and PTTSMC is developed. The proposed observer can ensure that the estimation error converges within predefined-time, even though the bound of the derivative of model uncertainty and external disturbance is unknown. Meanwhile, the trajectory tracking error can also be eliminated under the proposed controller quickly and accurately. Finally, the stability of the proposed control scheme is proved using the Lyapunov theory, and its effectiveness is verified through numerical simulations.