Building information modeling based design review and facility management: Virtual reality workflows and augmented reality experiment for healthcare project

Building information modeling (BIM) is often used in the AEC (architecture/engineering/construction) industry throughout the building’s lifecycle including design, operation and maintenance (O&M). Virtual reality (VR) can be used for real-time simulation of a user's physical presence in a 3D interactive environment. Augmented reality (AR) can be used to overlay the virtual information onto the real environment. Both can augment BIM capabilities. A healthcare patient room was selected for demonstration due to its future potential as part of a complex building type for the use of VR based design and integrated facility management (IFM). Three VR workflows (cinematic VR, Revit + Unity, and Revit + Fuzor) were explored for the immersive project presentation through VR storytelling and interactive design review and management of O&M data. An AR test (Unity + Vuforia) was conducted to visualize the related information for onsite IFM support after recognizing the object. ❧ In the first workflow, a VR linear film was made via Revit, Maya, Mettle Skybox, Handbrake, Redshift and After Effects to present the project through Oculus Rift HMD for seated experience of VR. ❧ In the second workflow, parameter data including the equipment’s manufacturer, cost, and website address was added to a project file in Revit. The geometry was exported to Unity using Maya as a go-between. The data was extracted from the Revit schedule to a text file. In Unity, the data was parsed based on a unique identifier and its data structure and linked back to the equipment through C# scripting based on a panel based user interface of Unity. Through customized programming, the outcome was a room in VR where equipment information could be appeared on canvas panels per user’s control input in real time. The HTC Vive, a head mounted display (HMD), was used to provide users with a walk-through VR experience. ❧ Although Unity is widely used in game and film industries and a free version is available, extra time and effort is spent in model modification via external software like Maya and model import and export. Hence, the third workflow was created, including Revit, a database of the equipment in Excel, Fuzor, and a customized link written in Python using the Fuzor Application Program Interface (API). Fuzor was chosen as it is a game engine based solution specifically tailored for the building industry. Moreover, other features already existing in Fuzor are beneficial for IFM, which includes an imbedded system of annotation, category customization, and colorization for layers to quickly differentiate various types of building information. Fuzor also has bi-directional synchronization with the Revit model and supports a VR environment which requires extra effort to establish for Unity. This synchronization with the Revit model without the need to use additional software makes it suitable for IFM as live BIM updates are needed during the O&M. An XML tool was developed to link the Excel sheet to the Revit and Fuzor models instead of using the inherent Revit parameters as in the first workflow. Packaged into a Python script, this tool can automate both the data extraction and the execution of importing the data into the Fuzor’s parameter window. This tool has immediate application potential because the Excel file can be an IFM database in a real project like a maintenance or repair logging schedule. ❧ A simple test based on Vuforia and Unity as a very preliminary exploration of AR. After several trials, including the usage of the object target in Vuforia, the model target was applied to recognize the shape of a laptop based on the corresponding pre-loaded 3d model and to overlay the related information on top of that laptop through the webcam connected to the computer. This application can be applied on site for facility management to better support the visualization of useful information including training videos. ❧ All the three VR workflows and the one AR test were evaluated and analyzed, followed by the conclusion drawn as the entire summary. At the end, future work recommendations were made, which include the further AR workflow development based on the AR test, a toolkit for smoothing the transition from Revit to Unity, and exploration towards the other VR and AR based workflows.