Hull Condition Monitoring and Lifetime Estimation by the Combination of On-Board Sensing and Digital Twin Technology

Abstract The industries using floating facilities such as FPSO and offshore wind turbine are increasing. Since these vessels have been fixed and operated in the installed area for a long period of time, they cannot be regularly docked, inspected and repaired as opposed to normal ship case, and limited to the inspection of the hull outer plates from under the water and the inspection of inside the tanks are conducted once every five years. These inspections involving visual inspections and thickness measurements at representative points, only examine the current state, and don’t evaluate quantitatively the future potential (remaining life) over the subsequent long operation period. To predict residual life in order to maintain the integrity of these structures, digital twin technology is proposed to realize this demand. This paper shows the method to develop digital twin assessment which solve the insufficiency of conventional monitoring and simulation method in order to utilize for risk-based inspection (RBI) and condition-based maintenance (CBM) to the operators.