Unmanned coaxial rotorcraft force and position control for physical interaction through contact

This paper addresses the problem of force and position control for an unmanned coaxial rotorcraft physically interacting with its environment through contact. The proposed control strategy equips the unmanned aerial robot with the capability to safely establish contact with the surfaces of its environment and apply desired forces on them while performing sliding maneuvers. A hybrid force/position control scheme is implemented, with the force controller being activated once contact is detected. Contact information is derived from force measurements and a hysteresis-based contact detection strategy. Extended experimental studies are conducted to evaluate the efficiency of the proposed methods.