Real Time Prediction of Ship Response to Ocean Waves Using Time Series Analysis

This paper describes the results of a feasibility study of using time series analysis methods to predict the real time motion of ships up to 10 seconds in advance. Potential application of this work are aircraft landing on ships, and motion compensation devices for handling loads at sea. It uses a statistical method that finds a time domain model which best fits an input wave sensor time history to the ship response time history. It is called a leading indicator method using an Auto- Regressive Moving Average (ARMA) model. It determines the relationship in situ, and can be redetermined as ship heading and sea conditions change. Tests of the algorithm on recorded ocean test data show good predictions of phase and amplitude for 2 to 4 seconds in advance and phase for 8 to 10 seconds in 8 second waves.