This work proposes a feedback control strategy capable of controlling the dynamics of an under-actuated Vertical Take-Off and Landing (VTOL) aerial vehicle to track a desired trajectory globally with respect to the initial conditions. The novelty of the proposed design is the idea of considering a cascade control paradigm in which the attitude dynamics, which are governed by means of a hybrid controller capable of overcoming the well-known topological constraints, and the position dynamics of the vehicle play respectively the role of the inner and of the outer loop. The stability properties of the proposed controller are then derived by analyzing the interconnection between a hybrid system, namely the closedloop attitude dynamics, and a continuous time system, given by the closed-loop position dynamics. The proposed algorithms are then demonstrated by means of simulations obtained considering a miniature quadrotor prototype. ©2013 IEEE.

This paper proposes a feedback control strategy to let the dynamics of a class of under-Actuated vertical take-off and landing (VTOL) aerial vehicle tracking a desired position and attitude trajectory globally with respect to the initial conditions. The proposed feedback controller is derived following an inner-outer loop control paradigm, namely by considering the attitude, which is governed by means of a hybrid controller so as to overcome the well-known topological constraints, serving as a virtual input to stabilize the aircraft position. Two different approaches, the first one obtained by assuming perfect knowledge of the vehicle dynamics and the second one obtained by considering uncertainties and exogenous disturbances, are proposed and compared by analyzing the interconnection between the hybrid attitude and the continuous-Time position closed-loop subsystems. The effectiveness of the obtained results is demonstrated by means of simulations and experiments using a miniature quadrotor prototype.