MARIN mooring line failure detection with gps

LIFELINE METHODOLOGY

The LifeLine methodology consists of two different but complementary approaches, the short-term-approach (STA) and the long-term-approach (LTA). The short-term-approach employs an event-based algorithm to assess the integrity of the mooring system. The algorithm aims to identify a mooring line failure by looking at the semi-instantaneous shift in the mean position of the floater. The long-term-approach employs a status-based algorithm. This algorithm aims to identify a mooring line breakage by comparing the zero-environment equilibrium position of the floater pre and post potential failure. The LTA monitors and updates the equilibrium position of the floater periodically. When a failure occurs the equilibrium position will change and after a sufficient amount of time it will be detected by the LTA. This approach is characterized by a longer detection time but it is not sensitive to data quality and extreme environmental conditions.