High-order fully actuated system approach for quadrotor control based on extended state observers
Shi Lu, Konstantinos Tsakalis, Yan Chen
Abstract
Quadrotor dynamics are characterized by underactuation, strong coupling, and susceptibility to external disturbances. Advanced control strategies are required to overcome these challenges and effectively execute desired maneuvers. This paper investigates the position and yaw tracking control of a 6-DOF quadrotor under practical disturbances. A high-order fully actuated (HOFA) approach is applied to reformulate the quadrotor model into three HOFA subsystems, which introduce high-order derivative terms of inputs, system states, and disturbances. To observe high-order terms and reject disturbances for control design, extended state observers (ESOs) are designed for the HOFA systems. The convergence of these ESOs is rigorously established using the Lyapunov stability theory. Simulation and experimental results are demonstrated to validate the effectiveness of the HOFA control design based on ESOs for quadrotors with practical disturbances, such as wind disturbances, aerodynamic drag, and ground effects.