Autotuning Aspects for Dynamic Positioning Systems

This paper considers aspects related to the problem of automatic tuning (autotuning) of dynamic positioning (DP) controllers for marine surface vessels. Autotuning involves automatic adjustment of controller parameters for shifting vessel operational conditions (VOCs), which encompass changing vessel dynamics and different operational tasks. A controller with fixed gains cannot behave equally well for all VOCs and autotuning can thus be very valuable in practice, saving time for commissioning and improving operational robustness. In this work, we review some previous work and discuss fundamental concepts within the subject area. We also propose a novel performance index for station-keeping purposes and use this index together with an autotuning algorithm which employs data generated from the index. Finally, some simulation results concerning station keeping of an offshore supply vessel operating in challenging sea-state conditions are included.