Ship Motion Effects on Human Performance

The somatosensory disturbances that cause motion sickness result in degradations of cognition, alertness, mood and motivation. We propose to empirically quantify the duration and extent of these effects and to describe them in a mathematical algorithm. Adiscrete event simulation tool (Micro Saint) will be used to model the human activity associated with a ship undergoing maneuvers at various speeds, in various sea states over several days. The model will include a range of motion sickness profilesinduced by a standard set of ship motion and hull designs estimated from existing data on whole body vibrations through 6 degrees of freedom. The motion sickness algorithm will then be used to degrade the response time and error rate of the simulated crewin accordance with these ranges. Model driven effects on workload and crew effectiveness will then be used to compare a variety of hull designs. The adequacy of the standard hull motion curves for predicting motion sickness will be assessed in Phase I.Phase II will be used to validate the ability of the Micro Saint ship model and the motion sickness algorithm to reliably predict at sea human degradation. The development of a modeling tool that will allow novel, agile hull designs to be rapidlyappraised for their effects on motion induced sickness will greatly reduce the costs involved in making and testing prototypes and estimating sea sickness from curves that may not apply to newer designs. The tool we propose uses empirical data toestimate the severity and duration of motion sickness on cognitive performance from novel hull designs in a variety of sea conditions and motions. Faster and more maneuverable ships are expected in many maritime environments from warships to ferry boats.The tool will allow the impact on crew effectiveness and comfort to be estimated early in the development of the ship. We anticipate monetary benefits to the designers and builders and a safer, easier voyage for passengers and crew.