Identification of wave profiles encountered by a ship with no forward speed using Kalman filter technique and validation by tank tests - long-crested irregular wave case -

This paper addresses a Kalman filter (KF) technique for identifying wave profiles encountered by a ship with no forward speed from measured ship responses. The KF technique has been applied to a series of tank test results for long-crested irregular head and oblique waves. In the test, an acrylic resin ship model is used. The method is validated by comparing the identified wave profile with reference wave measurement. It is shown that the accuracy of the wave identification can be improved by selecting more appropriate input, and further by combining two input signals. It is also used to estimate non-measured ship responses and its effectiveness is investigated. Finally, it is extensively applied to the future prediction of the wave profile and shown to be effective in predicting the wave profile a few cycles ahead.