Frequency-domain analysis for prediction of seasickness on ships

Oscillatory vertical motions of ships cause seasickness. There is a mathematical model that can be used to compute the percent of passengers who will get sick caused by vertical motions. However, the application of the mathematical model requires obtaining 2 hours of records of experimental or simulated ship motion data. Based on a filters analogy, this article proposes a new frequency-domain method for the calculation of seasickness incidence. The method can be applied to any sea power spectrum and any ship. Because it is based on response amplitude operators or transfer functions, which can be obtained with seakeeping simulation programs, the method can be applied even before the ship is built. The results of the method can be useful for ship design and for the analysis of best operation for passenger comfort.