568 Creative Construction Conference 2014 BIM CAVE for 4D immersive virtual reality Julian Kang a* , Karteek Kuncham b a Texas A&M University, College Station, TX 77843, U.S.A. b Texas A&M University, College Station, TX 77843, U.S.A. Abstract The CAVE (Cave Automatic Virtual Environment) system, first introduced in 1992 during SIGGRAPH, was designed to facilitate users to feel the sense of presence in a 3-dimensional computer model. Those who were in the CAVE system and surrounded by walls of screens and floor projecting viewer-centered images felt that they were actually in the 3D computer model. As Building Information Modeling (BIM) technology has been widely utilized in the construction industry, especially for informed decision making during preconstruction coordination meetings, one may wonder if the CAVE system would enable them to better review the model. Knowing that the original CAVE system was not designed to handle BIM data, our research team developed a BIM CAVE system on top of a commercial BIM application so that one can review the model in the CAVE system without having to convert BIM file formats. Our BIM CAVE system is currently consisting of 3 video walls and 3 personal computers projecting the rendered images of a NavisWorks model. The BIM CAVE application we developed controls the camera location and its aiming angle in the NavisWorks model, so that 3 video walls can project the viewer- centered images synchronously. Although our BIM CAVE system successfully enabled users to walk through a Building Information Model in real time, the BIM CAVE was not able to display the sequence of construction. Our research team recently updated our application for the BIM CAVE to display 4D construction sequence. This paper presents how our new application was developed. It also presents technical challenges we experienced and solutions we came up with for those challenges. Some example uses of the BIM CAVE are also presented in the paper. Keywords: 4D, BIM, CAVE, Virtual Reality 1. Introduction Due to increase in the complexity of projects in Architecture, Engineering, and Construction (AEC) industry the focus of visualization techniques has shifted from two-dimensional (2D) graphical representations to three- dimensional (3D) graphical representations, more specifically Building Information Modeling (BIM). BIM is more effective than the 2D drawings as it makes the visualization process easier. Apart from using BIM for the purpose of visualization, engineering analysis, conflict analysis, checking code criteria, cost engineering, as-built data, and budgeting it is also used to develop 4D models where activities of a schedule are attached to 3D components to simulate the construction sequence. As the projects become more complex, the complexity of 3D models also increases. The way humans interact with computers is totally different from their natural tendency of doing the same action in real world as visualizing 3D models on 2D screens limits the amount of information that can be gathered. Immersive virtual reality systems can narrow this gap between the real and the virtual world. Immersive Virtual Reality (IVR) is a technology enabling the users to feel the sense of presence in an artificially immersive environment. Construction professionals can use the immersive nature of the virtual reality to gain a better understanding of both qualitative and quantitative nature of space that they are designing (Bouchlaghem et al., 2005). In an immersive environment, Moreover, the increased field of view, both horizontal and vertical, will increase the sense of presence (Hatada et al., 1980). This is the main concept in CAVE (Computer Aided Virtual Environment) virtual reality systems to have the user surrounded by screens to create an immersive environment. Several documented studies have shown 4D CAD as a good visualization and schedule review tool. More project stakeholders can understand a construction schedule more quickly and completely with 4D visualization than with the traditional construction management tools (Koo and Fischer, 2000). 4D construction sequence in currently available commercial software on a single screen limits the spatial perception. In the case of large and complex facilities, use of these tools for schedule review may be time consuming as 3D objects are visualized on * Corresponding author. Tel.: +1-979-845-7055; fax: +1-979-862-1572. E-mail address:juliankang@tamu.edu