Ship Motions

Ship Motions is a program for predicting regular wave responses and statistical information from an initial hull geometry. The motion can be calculated with five degrees of freedom: heave, sway, roll, yaw and pitch. Different types of spectra may be used to generate the statistics, and wave spreading may be invoked. The wave angles may be from any direction between ahead and astern.

Ship Motions has been derived from a set of programs that have been developed over the past twenty years by the Department of Ship Science at the University of Southampton for the M.O.D. The program results are constantly being validated against full-scale ship trials and, when appropriate, against model tests in regular and irregular seas.

Ship Motions

1. Will the program calculate motions at zero speed?

Yes, the program will calculate ship motions at zero speed and is appropriate for speeds up to a Froude number of 0.3.

2. Will the progam calculate results if my vessel has a length / beam or a length / draught ratio less than 5 ?

No,  if the vessel's ratio is below, but close to 5 then extending the vessel with a section of low area will allow the program to run, but this must be used with great care.

3. Running the Sustained Speed calculation results in a 'Sustained Speed Error' pop-up. No sustained speed results are available in the report.

This occurs when the set acceleration exceeds 9.81 m/s². As Ship Motions is based on linear theory, calculating accelerations in excess of 1g is beyond its capability and will cause an error. Reduce the acceleration to 9.81 m/s² or less.

Release notes: 

Release changes are cumulative.

Release Notes for ShipMotions Version:

  • Compliant with Windows 10 up to and including version 1703.