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Creators/Authors contains: "Costa, Raphael"

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  1. The objective of this research was to evaluate and compare perceived fatigue and usability of 3D user interfaces in and out of the water. Virtual Reality (VR) in the water has several potential applications, such as aquatic physical rehabilitation, where patients are typically standing waist or shoulder deep in a pool and performing exercises in the water. However, there have been few works that developed waterproof VR/AR systems and none of them have assessed fatigue, which has previously been shown to be a drawback in many 3D User Interfaces above water. This research presents a novel prototype system for developing waterproof VR experiences and investigates the effect of submersion in water on fatigue as compared to above water. Using a classic selection and docking task, results suggest that being underwater had no significant effect on performance, but did reduce perceived fatigue, which is important for aquatic rehabilitation. Previous 3D interaction methods that were once thought to be too fatiguing might still be viable in water. 
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  2. The objective of this research is to compare the effectiveness of different tracking devices underwater. There have been few works in aquatic virtual reality (VR) - i.e., VR systems that can be used in a real underwater environment. Moreover, the works that have been done have noted limitations on tracking accuracy. Our initial test results suggest that inertial measurement units work well underwater for orientation tracking but a different approach is needed for position tracking. Towards this goal, we have waterproofed and evaluated several consumer tracking systems intended for gaming to determine the most effective approaches. First, we informally tested infrared systems and fiducial marker based systems, which demonstrated significant limitations of optical approaches. Next, we quantitatively compared inertial measurement units (IMU) and a magnetic tracking system both above water (as a baseline) and underwater. By comparing the devices rotation data, we have discovered that the magnetic tracking system implemented by the Razer Hydra is more accurate underwater as compared to a phone-based IMU. This suggests that magnetic tracking systems should be further explored for underwater VR applications. 
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