Exploring the Effects of Augmented Reality Guidance Position within a Body-Fixed Coordinate System on Pedestrian Navigation.

AR head-mounted displays (HMDs) facilitate pedestrian navigation by integrating AR guidance into users' field of view (FOV). Displaying AR guidance using a body-fixed coordinate system has the potential to further leverage this integration by enabling users to control when the guidance appears in their FOV. However, it remains unclear how to effectively position AR guidance within this coordinate system during pedestrian navigation. Therefore, we explored the effects of three AR guidance positions (top, middle, and bottom) within a body-fixed coordinate system on pedestrian navigation in a virtual environment. Our results showed that AR guidance position significantly influenced eye movements, walking behaviors, and subjective evaluations. The top position resulted in the shortest duration of fixations on the guidance compared to the middle and bottom positions, and lower mental demand than the bottom position. The middle position had the smallest rate of vertical eye movement during gaze shifts between the guidance and the environment, and the smallest relative difference in walking speed between fixations on the guidance and the environment compared to the top and bottom positions. The bottom position led to the shortest duration and smallest amplitude of gaze shifts between the guidance and the environment compared to the top and middle positions, and lower frustration than the top position. Based on these findings, we offer design implications for AR guidance positioning within a body-fixed coordinate system during pedestrian navigation.