Stabilization of quadrotor with air drag based on controlled Lagrangians method

In this paper, quadrotor with air drag is locally asymptotically stabilized by using controlled Lagrangians method. Three linear subsystems are got by conducting input transformations, linearization at the desired equilibrium, and invertible state transformations to dynamical model of quadrotor. Then subsystem with two under-actuation degrees is asymptotically stabilized by utilizing controlled Lagrangians method, and the other two subsystems are stabilized by PD controllers. The control law designed in this paper does not adopt outer/inner loop structure which depends on time-scale separate principle. Finally, simulation results verify the effectiveness of the designed control law.