On the Effect of User Tracking on Perceived Source Positions in Mobile Audio Augmented Reality

Mobile Audio Augmented Reality (AAR) allows users to live sonic experience where virtual sound objects are integrated seamlessly with the real-world acoustic space. This paper focuses on user perception of the virtual source position and the impact of different out-of-the-box user tracking and head orientation methods made available by iPad’s Augmented Reality (AR) camera tracking system and AirPods Pro. We propose an experimental procedure to rank tracking approaches according to perceived accuracy in positioning eye-level and ground-level virtual audio sources compared to real source references. To correctly provide a plausible AAR scenario, the proposed consumer electronic setup simulates a virtual sound source employing the scattering delay network (SDN) algorithm for calibrated dynamic auralisation and customized head-related transfer functions (HRTFs) for personalized user acoustics. The natural listening experience of real sound sources leverages AirPods’s active signal processing algorithms for headphone hear-through capabilities. The main result of this study lies in observing an accommodation effect by users interacting with different tracking approaches and sound source positions. In summary, participants tend to prefer more stable tracking solutions despite accuracy and wide head movement range.