Extended State Observer Based Hierarchical Control for quadrotor UAV

This paper presents an original control strategy based on the Extended State Observer -ESO- position and orientation control problem of a small rotorcraft Unmanned Aerial Vehicle subjected to unknown aerodynamic efforts. A hierarchical control approach is applied to separate the flight control problem into translational and rotational controllers based on the time-scale property of each subsystem. An Extended State Observer -ESO- is used to estimate the state and the unknown aerodynamic disturbances. Closed loop stability of the system is established. Numerical simulations are carried out and results are presented to demonstrate efficiency of the proposed control strategy.