Force control of robot floating on the water utilizing vehicle restoring force

This paper presents a force control strategy for a robot floating on the water. The central strategy reduces the number of vehicle actuators required for the force control by utilizing the restoring force/moment applied to the vehicle. In this research, the relationship between thruster outputs and the contact force/moment at the endpoint is derived taking the restoring force into account, and the range of the realizable contact force is calculated using this relationship. Moreover, a simulator of the vehicle motion is developed and the results of experiment by means of this simulator illustrate the validity of the proposed algorithm.