Prescribed-Time Attitude Tracking Control of UAV Based on Prescribed-Time Extended State Observer

The attitude tracking control of quadrotor unmanned aerial vehicle (UAV) is significantly affected by inertia uncertainties and external disturbances. In order to enhance the anti-interference ability of quadrotor UAV and achieve more accurate attitude tracking control, this paper proposes the prescribed-time tracking control method based on a prescribed-time extended state observer (PTESO). Firstly, the inertia uncertainties and external disturbances are regarded as lumped disturbance, an improved PTESO is designed to accurately estimate the non-vanishing lumped disturbance in a prescribed-time for achieving globally prescribed-time tracking control. Moreover, the PTESO has the ability to reconstruct unmeasured velocity information and solve common peaking value problem. Secondly, a prescribed-time controller based on the PTESO is developed to ensure that all states of the UAV system track the desired values within a prescribed-time, the convergence time is independent of initial values and system parameters, allowing users to allocate it arbitrarily. Finally, the stability is proven by Lyapunov theorem, simulations are conducted to validate the effectiveness of the control strategy.