Mixed-Sensitivity Controller Design for a Tethered UAV-buoy System

In this paper, the problem of a marine locomotive unmanned aerial vehicle (UAV) is formulated, in which a quadrotor UAV is connected to a buoy through a cable. Controlling the proposed system is challenging due to maritime environmental disturbances, necessitating enhanced robustness for optimal performance. This work aims at designing an H
∞
controller for the tethered UAV-buoy system to control the surge velocity of the buoy by manipulating the UAV’s thrust, using the mixed-sensitivity approach. We first obtain the dynamic model of the system to capture the coupling of the components, we then define the mixed-sensitivity control method, and finally design the H
∞
controller. Numerical simulations demonstrate the controller’s robustness as the system reaches the desired velocity and maintains stability when subjected to disturbances and uncertainties.