“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.

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

DOI forward links to this article:
[1] Bjrn Skaare and Olav Egeland (2006), doi:10.1109/JOE.2006.880394
[2] Y.J. Ha, B.W. Nam, S.Y. Hong, D.W. Jung and H.J. Kim (2018), doi:10.1016/j.oceaneng.2018.01.074
[3] Jinbo Wu, Zeyu Yang and Donglai Wu (2018), doi:10.1016/j.oceaneng.2018.09.025
[1] FALTINSEN, O.M. (1990). Sea Loads on Ships and Offshore Structures, Cambridge University Press, New York.
[2] FARD, M. P NIELSEN, F. G. (2001). Simulation of coupled vessel-load dynamics, Norsk Hydro, Exploration and Production, Bergen, Norway, Tech. Rep. NH-00036960, http://www.itk.ntnu.no/research/HydroLab/-reports/Fard2002.pdf.
[3] FOSSEN, T. I. JOHANSEN, T. A. (2001). Modelling and identification of offshore crane-rig system, Department of Engineering Cybernetics, Technical report www.itk.ntnu.no/research/HydroLab/reports/HydroLab dynamics.pdf.
[4] JOHANSEN, T. A. FOSSEN, T I. (2001). Observer and controller design for an offshore crane moonpool system, Department of Engineering Cybernetics, NTNU, Trondheim, Norway, Tech. Rep. 2001-13-1, http://www.itk.ntnu.no/research/HydroLab/reports/-hydrolaunc, control.pdf.
[5] JOHANSEN, T.A. FOSSEN, T.I. (2001). HydroLaunch free decay tests, Department of Engineering Cybernetics, NTNU, Trondheim, Norway, Tech. Rep. 2001-18-T, http://www.itk.ntnu.no/researcli/HydroLab/-reports/hydrolaunc, free decay.pdf.
[6] KORDE, U.A. (1998). Active heave compensation on drill-ships in irregular waves, Ocean Engineering 25, 541-561 doi:10.1016/S0029-8018(97)00028-0
[7] NEWMAN, J. N. (1977). Marine Hydrodynamics, Cambridge, MA: MIT Press.
[8] NIELSEN, F.G. (2002). Coupled hydrodynamics for the HydroLaunch vessel with load, Working note, Norsk Hydro, Exploration and Production, Bergen, Norway, NTNU, Trondheim, Norway, Tech. Rep. 2001-12-T, http://www.itk.ntnu.no/research/HydroLab/reports/-hydrolaunc, model.pdf.
[9] GREENHOW, M. YANBAO, L. (1987). Added masses for circular cylinders near or penetrating fluid boundaries-review, extension and application to water-entry, -exit and slamming, J. Ocean Engineering 14. 325-348 doi:10.1016/0029-8018(87)90031-X
[10] NSLT, (1998). The 3rd International Offshore Crane Conference, Kristiansand, Norway Norwegian Society of Lifting Technology.NSLT.
[11] NSLT, (200). The 5th North Sea Offshore Crane Conference, Aberdeen, Scotland. Norwegian Society of Lifting Technology (NSLT).
[12] NSLT, (2000). Underwater Lifting Operations, Stavanger, Norway (in Norwegian). Norwegian Society of Lifting Technology (NSLT).
[13] SAGATUN, S.I. (2002). Active control of underwater installation, IEEE Trans. Control Systems Technology 10, 743-749 doi:10.1109/TCST.2002.801783
[14] SAGATUN, S.I., FOSSEN, T. I. LINDEGAARD, K.P (2001). Inertance control of underwater installations, In Preprint IFAC CAMS, Glasgow. Scotland.
[15] SAGATUN, S.I., JOHANSEN, T. A., FOSSEN, T.I. NIELSEN, E G. (2002). Wave synchronizating crane control during water entry in offshore moonpool operations, In Proc. IEEE Conf. Control Applications, Glasgow.
[16] SÖDERSTRÖM, T. STOICA, P. (1988). System Identification, Prentice Hall, Englewood Cliffs, NJ.

  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}