Force control of manipulator/vehicle system floating on the water utilizing vehicle restoring force

This paper presents a force control strategy for a manipulator/vehicle system floating on the water. The control strategy reduces the number of actuators required for the force control by utilizing the restoring force/moment applied to the vehicle. We derive the relation between thruster outputs and the endpoint force/moment based on the kinematics and the dynamics of the system taking the restoring force into account. Using this relation, we calculate the realizable force/moment at the endpoint. We design a velocity-based control algorithm and illustrate the validity of the proposed algorithm by simulation