ESTIMATION OF SHIP ROLL PARAMETERS FROM MOTION IN IRREGULAR SEAS

A parametric identification technique is developed which is applicable to data acquired from a ship rolling in irregular unidirectional beam waves. It is shown that, if an appropriate parametric model relating the wave elevation history to the roll angular displacement history is adopted, it is possible to estimate all the unknown parameters in the model by suitably processing simultaneous, digitised records of the wave elevation history and the roll angular displacement history. Application of the method to experimental data acquired from a scale model of a ship is shown to result in parameter estimates with good convergence characteristics and final values in satisfactory agreement with corresponding values deduced from calm water tests. In particular, it is demonstrated that both the linear and non-linear damping coefficients in the parametric model can be estimated with reasonable accuracy through and analysis of roll data acquired in the irregular wave situation.

• Supplemental Notes:
  • Trans RINA, v 132 pt B, 1990, p 253 [14 p, 22 ref, 4 tab, 10 fig]
• Authors:
  • Kountzeris, A
  • Roberts, J B
  • Gawthrop, P J
• Publication Date: 1990

Language

• English

Subject/Index Terms

• TRT Terms: Damping (Physics); Rolling; Ship motion; Waves
• Old TRIS Terms: Irregular waves
• Subject Areas: Marine Transportation;

Filing Info

• Accession Number: 00699091
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Aug 14 1995 12:00AM