Direct Measurement of Motion on Fast Ferries

This paper describes a new identification method for the fast ferry motions by using the direct measurements on the ship’s board. The inertial sensor type of the Analog Devices (ADIS) 16364 is selected as a as suitable instrument to measure accelerations and velocity of the ship motions namely heave, pitch, and roll in time domain. Furthermore, the ship motion responses are transferred as the energy spectral density in frequency domain which are identified using the Fast Fourier Transform (FFT) method. For the case study, the measurement equipment was placed on the navigation room of MV. Dumai Line 12 recording in 15 minutes within ship voyage from Bengkalis to Batam in September 2021. Finally, the natural frequencies of heave, pitch, and roll motions are identified about 0.568 rad/s, 0.117 rad/s, and 0.227 rad/s, respectively.