In this paper, a robust control strategy is proposed to control the attitude and the altitude of quadrotors, based on an uncertainty and disturbance estimator (UDE). It is shown that the proposed controller can be tuned very easily, achieving the desired performance only by selecting an appropriate reference model and tuning a single parameter to tradeoff disturbance rejection with noise amplification in the control signal. The proposed control strategy is extensively validated in real-time applications with an experimental Quanser platform and also with a quadrotor prototype in real flight tests.
