A study on floating unit motion control strategy

Energy companies today increasingly look offshore and head towards deeper waters to assist fueling modern society. Semisubmersibles and drill-ships are often used to prospect and produce in remote environments. The oil rigs should be essentially kept on target. In this paper, the authors solve the problem of designing a Position Mooring (PM) system for barge ship. A mathematical model of a system describing the interaction between an unactuated barge ship and mooring system is presented. A PID control scheme is implemented to achieve PM for the vessel by changing the tension of the mooring ropes. Additionally, a scale model ship is built to test the proposed strategy. Hydrodynamic coefficients of the low speed model for PM ship are identified by suitable experiments.