A study of the influence of AR on the perception, comprehension and projection levels of situation awareness

In this work, we examine how Augmented Reality (AR) impacts user's situation awareness (SA) on elements secondary to an AR-assisted main task, i.e. not directly concerned by the main task. These secondary elements can still provide relevant information that we do not want the user to miss. A good understanding of user's awareness about them is therefore interesting, especially in a context of a daily use of AR, in which not all elements of user's environment are controlled. In this regard, we measured SA about secondary elements in an industrial workshop where the AR-assisted main task is a pedestrian navigation. We compared SA between three navigation guidance conditions: a paper map, a virtual path, and a virtual path with virtual cues about secondary elements. These secondary elements were either hazardous areas, for example, for mandatory helmets, or items which could be on user's path, for example, misplaced carts, boxes... We adapted an existing SA method evaluation to a real-world environment. With this method, participants were queried about their SA on three levels: perception, comprehension and projection about different items. We found that the use of AR decreased user's SA about secondary elements, and that this degradation mainly occurs at the perception level: with AR, participants are less likely to detect secondary elements. Participants still felt the most secure with AR and virtual cues about secondary elements.