# Smart Facility Management System Based on Open BIM and Augmented Reality Technology
## 2 Literature Review
### Utilizing AR Technology within the Construction Industry  
A review of recent trends with respect to AR technology utilization within the construction industry revealed that research was initially focused on the feasibility of applying visualization technology. [PERSON] proposed the feasibility of AR technology for on-site tasks with regard to infrastructure [19], while [PERSON] analyzed the display, tracking and server aspects of developing a system using AR based on wireless technology at construction sites and proposed an augmented reality system prototype for the inspection of steel pole construction [20]. Studies regarding AR authoring tools include research for developing a 3D modeling tool called 'Timmith' that allows modeling of AR through real-time capturing of external structures and rendering, allowing users to directly interact using augmented reality [21]. More recently, prototype developments that allow users to directly apply them at construction sites are actively carried out, with [PERSON] conducting a study on AR-CAD that overlays 3D CAD models on top of actual background images using a head-mounted display (HMD), allowing the discovery of spatial interference on blueprints during the design phase [22]. In their study, [PERSON] et al. demonstrated an augmented reality prototype for selecting the appropriate location for tower crane installation at high-rise construction sites and carried out testing procedures based on an actual construction blueprint [23]. Research into applying AR for FM has also been active recently. [PERSON] et al. conducted a study that proposed a novel method to support site construction and FM activities by allowing site workers to visually document construction issues or progress status through automatic access to the latest project information with AR overlays [24]. There have also been studies that proposed a natural marker-based AR framework that can digitally support facility managers when searching for FM items or when actually performing maintenance and repair work [25]. [PERSON] et al. proposed a smart FM system that improved existing maintenance processes and studied a new maintenance work process and implementation measures for the application of AR and VR technology [26]. A study by [PERSON] et al. proposed an augmented reality-based support system for collaboration among working-level stakeholders involved in the FM process, whereby AR was used not only as a tool for visualization of maintenance data but also as a tool for communication and alerts or displaying other coordination-related aspects for the whole team [27]. There have been studies that developed, tested and evaluated mobile BIM AR systems (Artifact) with cloud-based storage capabilities aimed at integrating BIM and AR systems to improve information retrieving process as well as operational efficiency during construction [28]. Research by [PERSON] and [PERSON] suggested a framework for visualization guidelines to implement objects such as pipes hidden behind walls or ceilings into AR, similar to X-rays [29]. There were also studies that used BIM to derive categories for fire safety equipment inspections as well as the development and validation of systems that can configure compiled data for visualization through AR [30]. In essence, visualization of non-visual data can be a very useful cognitive aid for identifying the information needed for decision-making in FM. To improve the efficiency of BIM applications, some studies have shown that the integration of AR technologies will help improve the usability and accessibility of BIM information [31; 32]. However, research demonstrating the efficiency or usefulness of AR from a scientific point of view was still lacking [33]. [PERSON] et al. found that the practical benefits of integrating AR and BIM models are somewhat limited and mentioned the importance of building a viable information search mechanism that meets user information needs in order to maximize the benefits [28].