Thrust vector V/STOL aircraft control based on angular acceleration estimation

In this paper, an adaptive-estimate-incremental nonlinear dynamic inverse (AE-INDI) flight control method is proposed to address the issue of inaccurate angular acceleration signals in the thrust vector control of vertical/short takeoff and landing (V/STOL) aircraft. First, considering the change of center of gravity (CG) caused by aircraft structure transformation, a model for the deflection of a three-bearing swivel duct nozzle is established. This model corrects the equations for the aircraft's moment of inertia and angular rate under CG changes. Second, to account for modeling uncertainty and sensor noise, the angular acceleration is estimated by using the aircraft's actuator information and known states. The uncertainty is then compensated for using adaptive techniques. Finally, a stability analysis is performed based on Lyapunov theory to prove the robustness of the control method. Simulation results show that the proposed controller effectively mitigates interference from model uncertainty, stabilizes affected states within 2 s, weakens the effect of unfavorable sensor noise, and reduces the angular rate noise variance by 77.63%, thus verifying the effectiveness and robustness of the control method.