Quick identification and dynamic positioning controller design for a small-scale ship model

Abstract

Dynamic positioning (DP) in marine robotics is a valuable feature that can significantly improve vessel performance at sea. In order to have satisfactory DP behavior, a sufficiently accurate mathematical model and parameters have to be known. Performing extensive identification trials at sea is a tedious and time consuming task. This paper demonstrates the application of a quick identification method based on self-oscillations (IS-O) applied to all controllable degrees of freedom (surge, sway and yaw) of a small-scale tanker model. In the paper we prove the consistency of the applied identification method. The identified model parameters are then used to tune DP controller parameters. The high quality of the model-based DP controller performance is demonstrated, proving the applicability of the IS-O method for DP controller tuning.