After the first model tests confirmed station keeping performance for Dynamic Positioned (DP) drilling units, many research projects have helped improve the positioning accuracy. Universities and research institutes developed their own closed loop dynamic positioning systems and started Joint Industry Projects to study the efficiency and interactions of thrusters. These models continue to challenge the state of the art, but are less suited to study operations with existing DP systems. Therefore, an alternative setup is developed in which the DP system to be used on board of the vessel can be coupled to the model tests or bridge simulations.

The new setup has been successfully applied to confirm station keeping offset limits and power utilization at model scale for the actual onboard DP system. Due to the applied Froude scaling the onboard DP system needs to respond faster than real time, but this proved feasible. The setup provides the best of both worlds: The model tests help to account for the hydrodynamic interactions correctly, while the onboard DP system ensures that all functionality in the control is identical to the actual operation. In addition, this setup allows institutions to study possible improvements to the onboard DP system in reproducible environmental conditions and in a safe and manageable manner. The paper describes the integration of an onboard operational system into a model test facility and a bridge simulator. It also discusses the main findings from the model tests and simulations thus far.

This content is only available via PDF.
You can access this article if you purchase or spend a download.