Abstract:
The introduction of calculation methods for motion induced interruptions (MII) in 1984<br />introduced a new way to quantify human factors in addition to the motion sickness index<br />(MSI). The 1990 Graham method for calculating MII uses a combination of a vessel\'s<br />acceleration and roll to determine a tipping" factor to calculate MII per minute. The<br />Applebee-Baitis (AB) method considered that the motions are implicitly considered in accelerations, and therefore did not require roll to calculate MII. This thesis examines and<br />analyzes the di"erences between the AB and Graham methods and compares their results<br />for a unique hull form shape, a cylindrical capsule, in rough seas to determine which method<br />is preferred. Two tests were performed by the Naval Surface Warfare Center, Carderock<br />Division (NSWCCD) for the National Aeronautics and Space Administration (NASA) on<br />the Orion Crew Exploration Vehicle (CEV) in post-splashdown conditions. A one-quarter<br />scale model of the CEV was tested at the Aberdeen Test Center in Aberdeen, Maryland.<br />Direct comparison of the analyzed data, MII sensitivity to location, and scaling analyses are<br />examined and future work to further the application of MII calculation methods are proposed.<br />The symmetry of the capsule leads to the assumption that roll and pitch-dominant<br />MII calculations should be on the same order of magnitude. They are not because both MII<br />methods only take roll-motions into account. The inclusion of both pitch and roll motions<br />for the MII calculations is proposed as future work. The Graham method was found to be<br />the more appropriate calculation because it is more conservative, and therefore preferred in<br />the context of crew safety.
