Augmented L1 adaptive tracking control of quad-rotor unmanned aircrafts

This paper addresses a new trajectory tracking controller for quad-rotor aircrafts in the presence of time-varying aerodynamic effect and bounded external disturbance using the novel L₁ adaptive control methodology augmented with nonlinear feed-forward compensations. The proposed augmented L₁ adaptive controller achieves uniformly bounded transient and asymptotic tracking of the output signal for any designated bounded reference trajectory. Finally, simulations of tracking a circular reference trajectory are performed to illustrate the validity of the proposed controller.