| Summary: | Thesis (MEng)--Stellenbosch University, 2016. ENGLISH ABSTRACT: Low frequency (0.1 Hz to 0.5 Hz) lateral and vertical motion present on ocean going vessels could cause motion sickness. ISO 2361-1 developed a means to predict motion sickness in the vertical direction, but did not propose a means on incorporating lateral motion. It was also hypothesised that motion on the SA Agulhas II is expected to be either more or less provocative depending on location. A modified six accelerometer array was developed in order to determine the lateral and vertical acceleration levels at any location on board the SA Agulhas II. Vertical acceleration was found vary along the width and length of the SA Agulhas II but was independent of height. Subjective responses of participants were collected from the personal details submission form and daily diary. It was reported that susceptibility towards motion sickness declined with age for the males. Females were found to be more susceptible than males. The percentage of motion sick participants, the percentage of vomiting participants and illness rating (N = 32) were correlated using Kendall's rank correlation. The percentage of motion sick participants and illness rating had the highest correlation coefficient (T) of 0.815. Participants spent most their time in the accommodation area, centred around zone D7. Daily maximum 6 h motion sickness dose values were determined at all locations on board the SA Agulhas II using vertical and lateral weighting filters for motion sickness. Illness rating correlated the best with both MSDVx;6h and MSDVz;6h. Linear and multiple non-linear regression analysis was used to determine the effects each direction, at zone D7, has on motion sickness. Motion in y-axis was determined to be insignificant. However multicollinearity was identified between x- and z-axis motion, which made determining the effects of each direction impossible. The contribution of each axis was then assumed to be the same and a linear regression model was developed to predict ...
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