Human Performance Factors and Measures in Hull Form Selection

High-speed (up to 30 knots) catamaran, trimaran, small waterplane area twin hull (SWATH), and Lifting Body type vessels have been built and tested to demonstrate technology for existing and evolving naval missions. A claimed advantage of these vessels is superior seakeeping in smaller ship sizes when compared to conventional monohulls capable of similar speeds. The effects of seakeeping qualities on human performance are an important consideration for hull form selection among these competing types. This is especially true when crew size reduction places a premium on the performance of each individual on board. The primary focus of this paper is a review of the development of technology for the assessment of human performance factors and measures in a vessel motion environment. Additionally, the paper briefly explores how two monohulls compare with a SWATH variant for one measure of human performance factors. Human performance of various tasks may be characterized by a combination of effects. These effects include motion induced interruptions (MII), motion induced fatigue (MIF), cognitive performance, motion sickness incidence (MSI), and habituation. To illustrate how these factors might be used in hull form trade-off and design studies, a few results are presented for MII for two monohulls and a SWATH. Vessel motions are obtained from calculated information for the monohulls and at-sea trials information for the SWATH