A Tension-based Position Estimation Approach for Moored Marine Vessels

This paper presents a novel idea on a tension-based localization approach as a redundancy measure to handle the situation when the position reference (posref) signals are not available or significant GNSS drifts occur, such as sudden ionospheric disturbances, for thruster-assisted moored vessels. The only information needed is the tension measurements from tension cells. This method can improve the redundancy and safety of offshore operation, by detecting and verifying posref failure modes. It can even take over the posref function if one no longer trust the main posref measurements. Based on a residual signal, a fault detection and estimation approach is introduced and verified through simulations.