Output feedback control design for quadrotor using recursive least square dynamic inversion

This paper proposes a new trajectory tracking output feedback control design for quadrotor unmanned aerial vehicles (UAVs) to manage stable flight in the outdoor environment with strong uncertainties, i.e., wind gusts. The controller is designed to handle unmeasured system states, disturbances, and uncertainties. Extended High-Gain Observers (EHGO) are employed to estimate the unmeasured system states and disturbances. A newly designed controller, namely Recursive Least Square with Dynamic Inversion (RLS-DI) controller, determines the coefficient of the input Jacobian to deal with the system uncertainties present in the input Jacobian. To deal with the underactuation characteristic inherited in the quadrotor, the controller and plant dynamics are separated into multi-time-scale structures. The stability of the closed-loop system is analyzed using the singular perturbation method. Through numerical simulations and outdoor experiments under the wind gust, the effectiveness of the proposed control algorithm is verified.