A PMM Experimental Research on Ship Maneuverability in Waves

Recently, much attention has been paid on the maneuvering characters of ships in waves. Apparently, ships steering in waves are subjected to linear wave loads at the encountering frequency. Nevertheless, the maneuvering characters of ships are more affected by the nonlinear wave drift forces at low frequencies. In the present work, to examine the wave effects on the ship maneuverability, a serial of towing tests with a Planer Motion Mechanism system (PMM) is carried out in waves. Forces and horizontal displacements of the model are measured throughout the tests. The measured data are analyzed by the Fourier analysis to obtain components at different frequencies. Discussion on the importance of the force components is made.