An Almost Globally Stable Tracking Controller for Quadcopters: A Model Predictive Control Approach

This paper introduces a novel cascade control structure with formal guarantees of uniform almost global asymptotic stability for the state tracking error dynamics of a quadcopter. The proposed approach employs a model predictive control strategy for the outer loop, explicitly addressing the non-zero total thrust constraint. The outer-loop controller generates an acceleration reference, which is then converted into attitude, angular velocity and acceleration references, subsequently tracked by a nonlinear inner-loop controller. A numerical case study validates the proposed scheme, highlighting its ability to track fast trajectories with small error.