Control of Underwater Manipulators Mounted on nn ROV Using Base Force Information

This paper presents a control scheme,for obtaining high maneuverability of underwater robot manipulators mounted on a remotely operated vehicle (ROV). The motions of an underwater manipulator can aflect the attitude and position of the ROV which should remain stationary in seabed operation. To compensate for the dynamic effect of the underwater manipulator on the ROY force-torque (F/T) information between the manipulator and the vehicle is used to regulate the states of the ROJ? When an F/T sensor is practically unavailable, a disturbance observer can fill the role of the F/T sensor. This paper proposes a disturbance observer for estimating the interaction forces between the ROV and the manipulator. A two-link manipulator mounted on an ROV is considered and numerical simulations are peyformed to demonstrate the improvement on the maneuverability of the proposed controller.