Page 15 - IJOCTA-15-2

M. Perala, S. Chandrasekaran, E. Begovic / IJOCTA, Vol.15, No.2, pp.202-214 (2025)

Figure 12. Yaw for 0 ◦
Abbreviation: RAO: Response amplitude operator Figure 15. Yaw for 90 ◦
Abbreviation: RAO: Response amplitude operator

4.3.3. Response amplitude operator for wave
heading of 45 ◦

Several key observations can be made by looking
at these RAO plots for a vessel at 45º wave inci-
dence (Figures 16–18). The surge RAO shows the
maximum response at lower frequencies, which
rapidly decreases with the increase in the wave
frequency. It confirms the vessel’s critical re-
sponse to long-period waves. The sway response
has a similar pattern but with minor oscillations Figure 16. Sway for 45 ◦
in the range of (1.0–1.5) rad/s. It suggests that
the controller addresses the secondary resonance
effects in the lateral motion, whereas the yaw
behavior showed more sensitivity under certain
ranges of wave frequencies.

Figure 17. Surge for 45 ◦
Abbreviation: RAO: Response amplitude operator

Figure 13. Sway for 90 ◦
Abbreviation: RAO: Response amplitude operator

Figure 18. Yaw for 45 ◦
Abbreviation: RAO: Response amplitude operator
4.4. Artificial intelligence-enabled control

The workflow of the AI algorithm for station-
Figure 14. Surge for 90 ◦ keeping begins with a hydrodynamic diffraction
Abbreviation: RAO: Response amplitude operator study of the numerical model under various sea
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