Simplifying orientation measurement for mobile audio augmented reality applications

Abstract

Audio augmented reality systems overlay the physical world with a virtual audio space. Today's smartphones provide enough processing power to create the impression of virtual sound sources being located in the real world. To achieve this, information about the user's location and orientation is necessary which requires additional hardware. In a real-world installation, however, we observed that instead of turning their head to localize sounds, users tend to turn their entire body. Therefore, we suggest to simply measure orientation of the user's body -or even just the mobile device she is holding -to generate the spatial audio. To verify this approach, we present two studies: Our first study in examines the user's head, body, and mobile device orientation when moving through an audio augmented reality system in a lab setting. Our second study analyzes the user experience in a real-world installation when using head, body, or device orientation to control the audio spatialization. We found that when navigating close to sound sources head tracking is necessary, but that it can potentially be replaced by device tracking in larger or more explorative usage scenarios. These findings help reduce the technical complexity of mobile audio augmented reality systems (MAARS), and enable their wider dissemination as mobile software-only apps.

AudioTorch

“…Some participants reported the head-tracking condition to be easier to adapt to, although their recognition rate was lower than in the device-tracking condition. As analyzed in [3], most of the participants held the device and head aligned with their body in both conditions.…”

“…Heller et al [3] conducted a navigation experiment comparing head tracking to device tracking. Results indicate that using device orientation does not dramatically influence the navigation performance nor the perceived presence.…”

A Survey on the Affordances of “Hearables”

“…AAR involves presenting users with context-specific audio information, often for highlighting local features within a museum or other place of public interest [23,24]. Research has found that the placement of a digital compass on the head, as opposed to other locations on the body, results in the best subjective ratings of realism in AAR situations [25], largely because ear-mounted compasses remain in fixed position to the eyes. For the same reason, ear-mounted compass information also offers important affordances for improving heading information within audio-based navigation applications.…”

Gaze-Guided Narratives

“…Unlike visual displays, audio guides allow for an unobtrusive user experience by not distracting the tourist's visual attention from the real world (see also [17]). In addition, audio can also be enriched to create immersive experiences including interactive multi-narrative soundscapes [42], 3D audio [6], or audio augmented reality [22].…”