SMP84: Improvements to Capability and Prediction Accuracy of the Standard Ship Motion Program SMP81

Abstract : The Standard Ship Motion Computer Program, SMP, was developed at the David Taylor Naval Ship Research and Development Center in 1981 as a prediction tool for use in the Navy's ship design process. SMP provides predictions of the six degrees of freedom responses of a ship (surge, sway, heave, roll, pitch and yaw) advancing at constant forward speed with arbitrary heading in both regular waves and irregular seas. Since 1981 a number of corrections and improvements were made to SMP which are detailed in this report. Corrections were made in the bilge keel viscous damping calculations for ships that have both a bilge keel and a skeg described to the same station. An improvement in yaw-roll coupling was made by using a different theory to compute hull lift damping. New predictions were incorporated into SMP to compute stabilized ship responses for active antiroll fins using fixed gains. Predictions of vertical wave induced loads were also incorporated into SMP. In addition, a new set of tables of severe ship responses is provided as part of the output. Keywords: Computer program documentation; Tables(data); Computer files.