Modelling and assessment of ROV capacity within an autonomous offshore intervention system

Autonomous Surface Vehicles and Remotely Operated Vehicles (ASV/ROV) system have received significant industrial and academic attention for offshore applications because of its low-risk operations in harsh and potentially dangerous conditions. This paper discusses the hydrodynamic and mission performance of three potential ROVs in an ASV/ROV system to support the decision making for ROV selection. The considered ROVs have different physical properties, dive characteristics and payload capabilities. For the ROVs, a nonlinear thrust control strategy is employed to reach the target. The ROV capability is tested against different current velocities and water depths. The results show that the ROV with the smallest normalized thrust, i.e. max vertical thrust normalised by the total payload, requires the lowest umbilical payout rate to reach the target. The tidal current capacity of the ROV, i.e. the current it is able to overcome, increases with a smaller target water depth and a larger normalized thrust.