Attitude control of spherical unmanned aerial vehicle based on Active Disturbance Rejection Control

Spherical Unmanned Aerial Vehicle (UAV) is a typical nonlinear system. Its un-modeled dynamics, internal and external disturbance can both affect the flight control, which makes the design of the controller more complex. In order to improve dynamic performance, static performance and robustness of the control system, an Active Disturbance Rejection Control (ADRC) scheme of spherical UAV is presented based on the analysis of the traditional PID control. First of all, through the arrangement of the transition process, the system can track the input signal and obtain the differential signal. It also can observe the unknown disturbance by using the extended state observer. Besides, the system implements compensation through the nonlinear feedback control law. Using MATLAB/SIMULINK as the simulation platform, according to the function, the controller is divided into multiple sub-systems, which are designed and finally connected to form a complete system. Simulation results show that the control system based on ADRC has high performance on resisting the disturbance and the un-modeled dynamics.