An Approach to Reducing Distance Compression in Audiovisual Virtual Environments

Perception of distances in virtual reality (VR) is compressed: objects are consistently perceived as closer than intended. Although this phenomenon has been well documented, it is still not fully understood or defined with respect to the factors influencing such compression. This is a problem in scenarios where veridical perception of distance and scale is essential. We report the results of an experiment investigating an approach to reducing distance compression in audiovisual VR based on a predictive model of distance perception. Our test environment involved photorealistic 3D images captured through stereo photography, with corresponding spatial audio rendered binaurally over headphones. In a perceptual matching task, participants positioned an auditory stimulus with respect to the corresponding visual stimulus. We found a high correlation between the distance perception predicted by our model and how participants perceived the distance. Through automated manipulation of the audio and visual displays based on the model, our approach can be used to reposition auditory and visual components of a scene to reduce distance compression. The approach is adaptable to different environments and agnostic of scene content, and can be calibrated to individual observers

Les retours tactile et kinesthésique améliorent la perception de distance en réalité virtuelle

National audienceResearch spanning psychology, neuroscience and HCI found that depth perception distortion is a common problem in virtual reality. This distortion results in depth compression, where users perceive objects closer than their intended distance. Studies suggested that cues, such as audio and haptic, help to solve this issue. We focus on haptic feedback and investigate how force feedback compares to tactile feedback within peripersonal space in reducing depth perception distortion. Our study (N=12) compares the use of haptic force feedback, vibration haptic feedback, a combination of both or no feedback. Our results show that both vibration and force feedback improve depth perception distortion over no feedback (8.3 times better distance estimation than with no haptic feedback vs. 1.4 to 1.5 times better with either vibration or force feedback on their own). Participants also subjectively preferred using force feedback, or a combination of force and vibration feedback, over no feedback.Des recherches en psychologie, neurosciences et IHM ont montré que la distorsion de la perception des distances est un problème courant en réalité virtuelle. Cette distorsion entraîne une compression des profondeurs, et les utilisateurs perçoivent des objets plus proches qu'ils ne le sont. Dans ce papier, nous nous concentrons sur le retour haptique et examinons comment le retour de force se compare au retour tactile pour réduire la compression des profondeurs. Notre étude (N = 12) compare l'utilisation du retour de force, le retour tactile vibratoire, la combinaison des deux ou l'absence de retour. Nos résultats montrent que le retour tactile et le retour de force améliorent la perception de la profondeur. L'estimation de distance est 8.3 fois meilleure que sans retour, par rapport à 1.4-1.5 fois avec retour tactile vibratoire ou de force non-combinés. Les participants ont également préféré utiliser le retour de force, ou une combinaison de force et tactile

Biomechanical fidelity of simulated pick-and-place tasks: impact of visual and haptic renderings

International audienceVirtual environments (VE) and haptic interfaces (HI) tend to be introduced as virtual prototyping tools to assess ergonomic features of workstations. These approaches are costeffective and convenient since working directly on the Digital Mock-Up in a VE is preferable to constructing a physical mockup in a Real Environment (RE). However it can be usable only if the ergonomic conclusions made from the VE are similar to the ones you would make in the real world. This study aims at evaluating the impact of visual and haptic renderings in terms of biomechanical fidelity for pick-and-place tasks. Fourteen subjects performed time-constrained pick-and-place tasks in RE and VE with a real and a virtual, haptic driven object at three different speeds. Motion of the hand and muscles activation of the upper limb were recorded. A questionnaire assessed subjectively discomfort and immersion. The results revealed significant differences between measured indicators in RE and VE and with real and virtual object. Objective and subjective measures indicated higher muscle activity and higher length of the hand trajectories in VE and with HI. Another important element is that no cross effect between haptic and visual rendering was reported. Theses results confirmed that such systems should be used with caution for ergonomics evaluation, especially when investigating postural and muscle quantities as discomfort indicators. The last contribution of the paper lies in an experimental setup easily replicable to asses more systematically the biomechanical fidelity of virtual environments for ergonomics purposes