Abstract
In this paper, a fractional Active Disturbance Rejection Control (ADRC) is proposed to track the desired trajectory workspace and solve the attitude control problem of a quadcopter Unmanned Aerial Vehicle (UAV). The ADRC is a robust nonlinear control being used recently to control the UAV technologies. It is mostly used to solve the major key challenges related to uncertainties, imperfect modeling, and external disturbances in a simple structure and easy way in control parameters tuning. The main idea of the ADRC control strategy is to introduce a fictitious state variable that represents the total disturbance. Then, this disturbance is estimated via an Extended State Observer (ESO). The estimated disturbance is fed back to construct a suitable controller, and hence decouple the system from all uncertainties and disturbances acting on the plant. A fractional State Error Feedback (SEF) controller is implemented and compared with the traditional SEF to enhance the system performance. Simulation results demonstrate the robustness and effectiveness of the proposed fractional control strategy in tracking the desired trajectory in the workspace of the quadcopter UAV.