skip to main content

Search for: All records

Creators/Authors contains: "Quarles, John"

Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher. Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?

Some links on this page may take you to non-federal websites. Their policies may differ from this site.

  1. This research investigates the effect of scaling in virtual reality to improve the reach of users with Parkinson’s disease (PD). People with PD have limited reach, often due to impaired postural stability. We investigated how virtual reality (VR) can improve reach during and after VR exposure. Participants played a VR game where they smashed water balloons thrown at them by crossing their midsection. The distance the balloons were thrown at increased and decreased based on success or failure. Their perception of the distance and their hand were scaled in three counterbalanced conditions: under-scaled (scale = 0:83), not-scaled (scale = 1), and over-scaled (scale = 1:2), where the scale value is the ratio between the virtual reach that they perceive in the virtual environment (VE) and their actual reach. In each study condition, six data were measured - 1. Real World Reach (pre-exposure), 2. Virtual Reality Baseline Reach, 3. Virtual Reality Not-Scaled Reach, 4. Under-Scaled Reach, 5. Over-Scaled Reach, and 6. Real World Reach (post-exposure). Our results show that scaling a person’s movement in virtual reality can help improve reach. Therefore, we recommend including a scaling factor in VR games for people with Parkinson’s disease.
    Free, publicly-accessible full text available August 1, 2023
  2. 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.
  3. Our objective in this research is to compare the usability of three distinct head gaze-based selection methods in an Augmented Reality (AR) hidden object game for children: voice recognition, gesture, and physical button (clicker). Prior work on AR applications in STEM education has focused on how it compares with non-AR methods rather than how children respond to different interaction modalities. We investigated the differences between voice, gesture, and clicker based interaction methods based on the metrics of input errors produced and elapsed time to complete the tutorial and game. We found significant differences in input errors between the voice and gesture conditions, and in elapsed tutorial time between the voice and clicker conditions. We hope to apply the results of our study to improve the interface for AR educational games aimed at children, which could pave the way for greater adoption of AR games in schools.
  4. 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.