Raziyeh Babaei - Department of Electrical Engineering, Imam Khomeini International University, Qazvin,
Amir Farhad Ehyaei - Department of Electrical Engineering, Imam Khomeini International University, Qazvin, Iran

In this paper, to overcome the problem of hovering a quadrotor system, under aerodynamic effects, an optimal recursive backstepping controller is designed. One of the main achievements of this study is to propose a nonlinear efficient observer based on extended kalman bucy filter (EKBF) to estimate the unmeasured states of the system. Our control method is robust against perturbations and ensures the stability of the system by using Lyapanv theory. In order to improve the system response, the controller coefficients are also optimized by using the genetic algorithm. Finally, simulation results are included to show that the performance of the quadrotor UAV with the proposed controller and observer is quite satisfactory. The results demonstrate better robustness against the aerodynamic effects in comparison with previous works

Quadrotor, backstepping, Lyapunov theory Control, Genetic Algorithm, Extended Kalman Bucy Filter, Aerodynamic Effects