A FAS Approach for Robust Trajectory Tracking Control of a 3-DOF Quadrotor

This paper proposes a quadrotor control strategy based on the fully actuated system (FAS) approach, aiming to enhance trajectory tracking robustness under external disturbances. By establishing the dynamic model of a three-degree-of-freedom (3-DOF) planar quadrotor system, we develop a controller by the FAS approach that analytically computes input derivatives and integrates a novel robust compensator to mitigate high-order disturbances. The proposed method eliminates the need for designing extended observers to estimate the higher-order derivatives of the input, thereby simplifying the system structure and avoiding the cumulative estimation errors observed in conventional approaches. Theoretical contributions include a Lyapunov-based stability proof demonstrating bounded convergence of tracking errors into an ellipsoidal region centered at the origin. Simulation results validate the framework's effectiveness. The method demonstrates practical significance through its ability to maintain physically realizable control inputs while handling bounded disturbances. This work provides direct implications for applications requiring precise trajectory tracking in adverse conditions.