Impact of Mobile Augmented Reality System on Cognitive Behavior and Performance during Rebar Inspection Tasks

Mobile augmented reality (MAR) enhances the real world through the superimposition of computer-generated information while not interfering with a users' mobility, having great potential to support various construction tasks. However, such information may lead to cognitive overload and, thus, could lead to adverse effects on the performance of tasks. Also, the narrowing of a user's field of view that comes with MAR use could limit his or her ability to notice events in their surroundings. Therefore, it is important to understand how MAR use affects cognitive behavior, as well as task and safety performance for better design and applications of MAR in construction. As a preliminary investigation, this study conducted laboratory simulations of rebar-inspection tasks and compared the cognitive load (CL), task performance (TP), and situational awareness (SA) of users of two types of MAR systems-i.e., head-mounted and handheld-against those of inspectors using traditional paper-based methods. In particular, participants' CL was measured with the National Aeronautics and Space Administration's Task Load Index (NASA-TLX), their TP by completion time and the number of rebars correctly detected, and their SA with Taylor's Situation Awareness Rating Technique (SART). Based on the results, we discuss the impact of the MAR system on rebar-inspection tasks from both cognitive and safety perspectives.