In this work, we investigate the influence of different visualizations on a manipulation task in virtual reality (VR). Without the haptic feedback of the real world, grasping in VR might result in intersections with virtual objects. As people are highly sensitive when it comes to perceiving collisions, it might look more appealing to avoid intersections and visualize non-colliding hand motions. However, correcting the position of the hand or fingers results in a visual-proprioceptive discrepancy and must be used with caution. Furthermore, the lack of haptic feedback in the virtual world might result in slower actions as a user might not know exactly when a grasp has occurred. This reduced performance could be remediated with adequate visual feedback.
In this study, we analyze the performance, level of ownership, and user preference of eight different visual feedback techniques for virtual grasping. Three techniques show the tracked hand (with or without grasping feedback), even if it intersects with the grasped object. Another three techniques display a hand without intersections with the object, called outer hand, simulating the look of a real world interaction. One visualization is a compromise between the two groups, showing both a primary outer hand and a secondary tracked hand. Finally, in the last visualization the hand disappears during the grasping activity.
In an experiment, users perform a pick-and-place task for each feedback technique. We use high fidelity marker-based hand tracking to control the virtual hands in real time. We found that the tracked hand visualizations result in better performance, however, the outer hand visualizations were preferred. We also find indications that ownership is higher with the outer hand visualizations.
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Over My Hand: Using a Personalized Hand in VR to Improve Object Size Estimation, Body Ownership, and Presence
Best Paper Award. When estimating the distance or size of an object in the real world, we often use our own body as a metric; this strategy is called body-based scaling. However, object size estimation in a virtual environment presented via a head-mounted display differs from the physical world due to technical limitations such as narrow field of view and low fidelity of the virtual body when compared to one's real body.
In this paper, we focus on increasing the fidelity of a participant's body representation in virtual environments with a personalized hand using personalized characteristics and a visually faithful augmented virtuality approach. To investigate the impact of the personalized hand, we compared it against a generic virtual hand and measured effects on virtual body ownership, spatial presence, and object size estimation. Specifically, we asked participants to perform a perceptual matching task that was based on scaling a virtual box on a table in front of them. Our results show that the personalized hand not only increased virtual body ownership and spatial presence, but also supported participants in correctly estimating the size of a virtual object in the proximity of their hand.
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- Award ID(s):
- 1725554
- NSF-PAR ID:
- 10134951
- Date Published:
- Journal Name:
- . Proceedings of the 6th ACM Symposium on Spatial User Interaction (SUI 2018)
- Page Range / eLocation ID:
- 60 to 68
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3267782.3267920
