Output-Feedback Critical Damping Double Integral Angular Velocity Control With Model-Free Observer for Quadcopter Applications

This study attempts to address the angular velocity regulation problem associated with quadcopters under constraints such as model-plant mismatch, uncertain loads, and limited measurement capability. The proposed solution is an output-feedback structure that includes an angular velocity observer, active damping, and a disturbance observer to enhance the performance of the closed-loop system, which provides the following features: first, the model-free observer yields estimates of angular velocities by stabilizing the diagonalized error dynamics; second, the output-feedback double integral control with feed-forward compensation terms stabilizes the angular velocity errors while satisfying a predetermined critically damped performance. An experimental platform provided by Quanser demonstrates the effectiveness of the proposed technique.