A 3-DOF mathematical model is presented in this post to investigate the maneuverability of any low-speed ship with single-rudder/single propeller configuration. The theoretical background can be referred to this article. The block diagram of the model is shown as
The parameters of the ship are masked, and therefore the setting of the model becomes easy.
A circular motion using the model is plotted and the result is shown in the next figure:
The model can be found here.