ANZIAM J. 47(EMAC2005) pp.C915--C933, 2007.

Modal analysis of a small ship sea keeping trial

A. Metcalfe

L. Maurits

T. Svenson

R. Thach

G. E. Hearn

(Received 16 March 2006; revised 15 May 2007)

Abstract

Data from sea keeping trials of a Scottish trawler are analyzed. The trawler sailed an octagonal course, each leg took over 20 minutes and data recorded twice a second. The natural frequencies of vibration for each of the six rigid body modes are estimated from the heave, surge, sway, pitch, yaw and roll time series. The time series are investigated for evidence of non-linearity. A time domain model is fitted to a roll time series, and second order amplitude response functions are then obtained using autoregressive estimators.

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Authors

A. Metcalfe
L. Maurits
T. Svenson
R. Thach
School of Mathematical Sciences, University of Adelaide, South Australia. http://www.maths.adelaide.edu.au/stats/staff/ametcalfe.html
G. E. Hearn
School of Engineering Sciences, University of Southampton, England.

Published July 30, 2007. ISSN 1446-8735

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