Development of a Spatial Alignment System for Interacting with BIM Objects in Mixed Reality

This study proposes a Two-points Spatial Alignment System (TSAS) for accurate positioning of Building Information Modeling (BIM) objects in Mixed Reality (MR) environments at construction sites. Conventional spatial alignment methods present limitations: marker-based approaches require precise marker installation and setup in predefined locations, while drag-based methods rely considerably on user manipulation skills. TSAS utilizes Y-axis rotation and vector-based scaling mechanisms to facilitate alignment processes. Through usability evaluation with 30 participants in MR environments, TSAS demonstrated a performance with a 50.3 mm alignment error, compared to marker-based (64.0 mm) and drag methods (199.7 mm). A one-way Analysis of Variance (ANOVA) confirmed that these differences in accuracy were statistically significant (p < 0.001). Notably, TSAS meets the Korean building regulation’s tolerance while maintaining consistent accuracy in indoor environments. Although the marker method showed better efficiency in operation time, this evaluation excluded initial installation time requirements. The usability evaluation suggests this approach could be beneficial for BIM visualization and review processes in construction settings. Future research will focus on validating the system’s performance in diverse construction environments, including larger buildings and complex sites.