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“Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results”

Authors: Tor A. Johansen, Thor I. Fossen, Svein I. Sagatun and Finn G. Nielsen,
Affiliation: NTNU, Department of Engineering Cybernetics and Norsk Hydro
Reference: 2004, Vol 25, No 1, pp. 29-44.

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Keywords: crane control, heave compensation

Abstract: A new strategy for active control in heavy-lift offshore crane operations is suggested, by introducing a new concept referred to as wave synchronization. Wave synchronization reduces the hydrodynamic forces by minimization of variations in the relative vertical velocity between payload and water using a wave amplitude measurement. Wave synchronization is combined with conventional active heave compensation to obtain accurate control. Experimental results using a scale model of a semi-submerged vessel with a moonpool shows that wave synchronization leads to significant improvements in performance. Depending on the sea state and payload, the results indicate that the reduction in the standard deviation of the wire tension may be up to 50%.

PDF PDF (1896 Kb)        DOI: 10.4173/mic.2004.1.2

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  title={{Wave Synchronizing Crane Control during Water Entry in Offshore Moonpool Operations - Experimental Results}},
  author={Johansen, Tor A. and Fossen, Thor I. and Sagatun, Svein I. and Nielsen, Finn G.},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}


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