Project Details

Project Description

The Hong Kong University of Science and Technology (HKUST) campus carries a vision of creating a digital twin, which digitizes the physical world with different facility systems integrated into a single hub. The project will significantly enhance facility management (FM) like engineering analyses, operation management and maintenance. Diverse data sources are available, including building information modeling (BIM), geographic information system (GIS), Internet of Things (IoT) and building management system (BMS).



    Objectives:

  • To support facility management activities at Campus Development Office (CDO) and Campus Management Office (CMO)
  • To further extend the digital twin to major subcomponents and other SSC IoT projects such as aircon analytics and SCAN+ monitoring to the benefits of the entire HKUST community
  • To improve the visualization display of the digital twin by incorporating virtual tour technology for both onsite and remote user experience

Research Achievements



BIM-GIS Model Creation and Integration

Considering openBIM, a IFC data model is proposed for seamless BIM-GIS integration, capturing a realistic 3D topology of the entire HKUST in rich details. IFC schema is seamlessly interoperable with GIS platform, where an online dashboard is developed for web-based model interaction and query



BIM-GIS-IoT Data Integration

The BIM-GIS model is then integrated with distributed IoT data based on openGIS, where an extended CityGML model is proposed to incorporate real-time IoT data, which are parsed from other HKUST portals with Python API. A mobile app is developed for general public to interactively query the operational performance, like indoor air qualities.



BIM-GIS-BMS Integration

The BMS data are also integrated into the BIM-GIS model, including air-conditioning system performance. With an open ontology called Brick schema, the functional interaction between BMS and surrounding geometry is effectively captured.




BIM- GIS-Blockchain Integration

A secure openCDE is developed with a blockchain model, which encrypts FM data and authenticates a staff's permission level before granting access privileges. Data sharing are guaranteed high integrity, authentication and transparency among different FM parties.


BIM-GIS Model Creation and Integration


A workflow is developed to realize BIM-GIS data integration based on openBIM, such that a large-scale digital twin is generated to support both microscopic analyses and macroscopic management. Hence, a IFC data model is proposed to govern the attribute modeling in BIM, as well as the data transfer to GIS. Based on the proposed IFC schema, individual buildings/spaces of an area are constructed. In addition, a methodology is proposed to reduce the file size, by combining architecture components while keeping room masses separate, minimizing the graphical rendering loads for smoother visualization.

3D BIM models were created for the whole campus in Revit. The BIM reconstruction totally covered more than 60 buildings, 20,000 rooms and floor area 500,000 square meters. Individual BIM sub-models are imported to a GIS platform, which effectively supports IFC data interoperability with a BIM-GIS data mapping scheme, and geo-referenced to the appropriate location, such that the overall topology is reconstructed. The BIM-GIS model integrates various data sources (including buildings, landscapes and topology) into a single hub, which is published online to allow information query or management by different parties. The figure below shows the web dashboard developed for interacting with the BIM-GIS model (e.g. component attribute query).

Model Verification with Laser Scanning
The BIM models were validated by field audit, and laser- scanned point cloud data imported to Revit for alignment verification.

BIM-GIS-IoT Data Integration


Facility condition monitoring is supported by integrating IoT data with BIM-GIS. BIM/GIS stores a digital model of the facility, and locations of individual IoT device are identified in the digital model and then associated it with the device-specific measurements from the correct device. A data model based on CityGML is developed to formalize the necessary IoT-related attributes. Different points-of- interest (POIs) data sources and IoT data from other HKUST databases were effectively extracted and integrated into the BIM-GIS model. These include the real-time pedestrian counts from the HKUST Pulse system based on WIFI localization, the IAQ measurements from the SCAN platform such as temperature and humidity at different locations.

An interactive mobile app is also developed for querying real-time IAQ at a user-specified room as demonstrated in the video below. For smoother user experience in mobile devices, the BIM models were down-sized and exported to a game engine.



Virtual Tour

Panoramic images are integrated with the digital twin platform for different purposes. A virtual tour platform is developed, and 360-degree panorama scenes with floorplans are integrated to provide a realistic and holistic view of facilities and the environment to better understand the target facilities and environment. Various hotspots are labeled in panorama scenes to show various feature types, while an inserted map or floorplan, generated from BIM software, is placed to show the scene's location. In this way, the overall visualization display is also enhanced with the combination of digital twin models and panoramic images.


BIM-GIS-BMS Integration



To integrate the BIM-GIS model with the BMS data (e.g. HVAC information), a data model based on the Brick ontology schema is proposed to formalize the semantic descriptions of building assets and their relationships. The figure above summarizes the overall workflow of generating a Brick ontology model by integrating the openBIM and BMS data. The Brick model summarizes the hierarchical relationships between the HVAC components (e.g. AHUs, VAVs, zones and points). Hence, the operational statuses like supply air temperature can be monitored, which can enable energy performance evaluation or predictive maintenance of HVAC components.

BIM-GIS-BMS data integration based on open ontology HVAC information from BMS platforms were extracted, while spatial information were extracted from BIM models based on IFC files to ensure data interoperability under openBIM standard. Python programming was implemented to automatically process the data sources and generate a Brick model. By integrating the BIM-GIS and BMS data, facility managers can effectively query necessary information for routine/ proactive/ predictive maintenance of the HVAC components, as well as IAQ assessment for optimizing occupant comfort or energy efficiency.



BIM-GIS-Blockchain Integration



An openCDE framework based on blockchain is developed and integrated with the BIM-GIS platform for secure data management among different parties. The blockchain data model provides a unified and data-neutral record to track who did what and when throughout the lifecycle of a facility. The framework consists of two layers, (1) a blockchain layer for integrating graphical and non-graphical information from different data sources in a secure manner and (2) a shared repository for the storage and graphical and non-graphical information. The blockchain layer provides the security of irreversibility and prevents the information from being over-written and provides a method for viewing/auditing information as required by FM processes, securely and effectively.


The figure below shows a typical facility maintenance process supported by the blockchain-enabled openCDE. The process is initiated by a FM manager. A FM staff collects building component information (e.g. location, historical maintenance records, sensor measurements) to assess the condition of building components against pre-determined criteria. After an assessment, the FM staff assigns a maintenance request if the building component is eligible for maintenance. A blockchain record is created and the linked data are uploaded to the common repository of the openCDE. Content-based cryptographic hashes of the documents uploaded to the common repository are recorded so that the authenticity of the documents and information may be verified at a later stage when required. Subsequently, the maintenance trade, tools, and procedure are defined by the FM staff, following which a maintenance work order is generated, and blockchained for the FM manager to track the lifecycle of the maintenance process and verify the authenticity of the required information, using the cryptographic references stored on the blockchain, following which he/she schedules the maintenance process. The maintenance is conducted by FM staff and the BIM model is updated which is also recorded in the blockchain to track the life cycle of BIM during the operation phase.