Efficient force exertion for aerial robotic manipulation: Exploiting the thrust-vectoring authority of a tri-tiltrotor UAV

Christos Papachristos, Kostas Alexis, Anthony Tzes

Abstract: The issue of efficient large force and moment exertion with Unmanned Aerial Vehicles (UAVs) is the subject of this paper. Inspiration is drawn from the vision of UAVs that are capable of autonomously executing industrial activities, or effectively reconfiguring their environment via forceful interaction. Therein, the technical shortcomings of the potential utilization of conventional underactuated UAV platform designs are examined, in terms of operational effectiveness-versus-safety. The innovative implementation of the direct thrust-vectoring authority of tiltrotor UAV types for forceful interaction is proposed, and its associated technical contributions are analyzed. A methodology is developed for controlled forward thrust force and rotating moment exertion, while ensuring safe operation near the hovering attitude pose. A large force-requiring scenario is assembled, consisting of a realistically-sized object laid on solid ground, regarded as a path-hindering obstacle to be forcefully removed by the UAV via pushing manipulation. To this purpose, a high-end autonomous tiltrotor UAV is employed in order to achieve this environment modification task, relying on a properly synthesized control structure.