Attitude Control of Quadrotor UAV Based on LADRC Method

Quadrotor Unmanned Aerial Vehicle (UAV) contains nonlinearity and strong coupling, and it is susceptible to external disturbance. Herein, a design method of attitude control of UAV is presented based on Linear Active Disturbance Rejection Control (LADRC) theory. A transition process is firstly arranged to decrease the overshoot and improve the rapidity of the system, then an Extended State Observer (ESO) is processed as broad-band to reduce the number of adjusting parameters, meanwhile the state coupling together with external disturbances are taken as the total disturbance of the system. Furthermore a Linear Extended State Observer (LESO) is constructed and the total disturbance is estimated, and a linear state feedback control element is designed to compensate the total disturbance. Simultaneously, the designed system is compared with the Model Reference Adaptive Control (MRAC) method. The simulation and experiment results show that the designed LADRC system can quickly estimate and eliminate the total disturbance on the attitude.