Position Trajectory Tracking of a Quadrotor based on L1 Adaptive Control

This paper presents an adaptive backstepping controller for the position trajectory tracking of a quadrotor. The design adopts and modifies the L1 adaptive control approach for nonlinear reference systems to fit into the backstepping design and to decouple the nominal controller from the adaptation. The controller compensates for all model uncertainties and all bounded disturbances within a particular frequency range. A stability criterion and verifiable bounds on the system signals are derived. Simulations and experimental tests demonstrate the powerful properties of the presented controller.