Amplitude, phase and frequency fuzzy controllers of a fast ferry vertical motion

Based on the study of the behaviour of a fast ferry, Mamdani-type fuzzy systems have been developed to control the vertical motion of the craft. The sources of the knowledge for designing the controllers are the experimental data of the performance of this ship in regular waves, the description of the vertical dynamics of the craft, and the model of some actuators (flaps and T-foils) that have been added to the craft. Amplitude, phase and frequency fuzzy controllers have been implemented to control the working angles of the fins in order to reduce the vertical acceleration of the ferry, which is the main cause of the seasickness. The controllers have been simulation tested in regular waves and the results are encouraging. Consequently, by reducing the pitch motion of the fast ferry, the sailing conditions are improved and the operational range is enlarged.