Underwater target tracking of offshore crane system in subsea operations

Abstract

Accurate underwater target tracking during subsea lowering is a complex technological problem in offshore installation and deep ocean mining. It involves the real-time motion compensation of both combined effects from flow-induced vibration on the cable-payload and wave-induced motions on the host vessel. A target tracking mechanism for a planar motion was theoretically derived and simulated in this paper under both regular and irregular wave motions. The simulation results have shown that the proposed target tracking system, by using PID controller integrated with hydrodynamic effects of both surface vessel and subsea payload, has followed the movable subsea target with small vicinity. The findings of this paper can be further implemented in the development of automatizing the subsea operations of the offshore crane system.