Digital Twins and Extended Reality: Opportunities and Challenges of Integrated Applications

Dear Colleagues,

The architecture, engineering and construction (AEC) industry and the digital heritage domain are both benefiting from the augmented reality (AR) and virtual reality (VR) revolutions. Architectural representation, along with advanced tools and techniques of digital visualization, enables users to increase the informative value of digital models.

Researchers and architects are increasingly capable of devising complex scenarios, characterised by buildings of high historical-cultural value, along with historical and modern infrastructure, archaeological sites, and museums, and have directed their resources towards innovative processes such as scan-to-BIM, BIM projects, HBIM projects, BIM-to-FEA, CoSim, BEM, InfraBIM, able to digitise and transform simple point clouds (3D survey data) into informative digital models.

Within this context, interoperability and data sharing become key factors for developing digital models oriented towards different purposes and uses, such as restoration, building site design, energy and structural analysis, cost evaluation, valorisation, knowledge sharing and virtual representation.

On the other hand, these innovative forms of representation present low levels of interactivity and immersion. The digitisation of built structures, whether modern or ancient, requires a specific cognitive approach that aims to create a faithful and accurate representation of geometries. The aim in so doing is to capture specific levels of detail and accuracy (LOD-LOA), as well as the morphological and constructive characteristics of each element, according to the final purpose of the digital twin (DT).

Therefore, acquiring quantitative and qualitative data relevant to the management of complex scenarios DT integrated with VR and AR can improve the use of 3D digital models. Users who may benefit from these applications range from professionals involved in the life cycle of the building to those imagining new forms of virtual tourism.

Within this framework, the use of drones (indoor and outdoor) can provide additional support in documentation activities and data interpretation. More specifically, drones can support the survey of those parts of buildings or sites that are not always easily accessible or inspectable (e.g., collapsed parts of a building due to earthquakes or simply roof or tall buildings challenging to access). Further, drones can provide solid support to developing a DT of the recorded objects or sites, allowing the development of 2D measured drawings and 3D models obtained either by integrating aerial data with those obtainable using ground survey instruments or simply by using UAV to survey and represent built environments.

Additionally, the resulting model can be implemented and updated during the various phases of the maintenance/restoration/reuse of a building or a site, becoming fundamental to the control and simulation of activities and acting as a reference for all the different actors involved in site conservation and management, ranging from surveyors and archaeologists to architects, conservators, engineers and plant engineers.

Accordingly, the digital representation—acquired either by photogrammetry or LiDAR—can be used for dissemination and communication. Within this context, VR and AR play a key role. Virtual and augmented experiences allow museums, cultural institutions, and archaeological sites to propose new forms of virtual–visual storytelling (VVS), allowing virtual tourists (who cannot access the site) to raise their awareness remotely.

Consequently, we invite the submission of articles dealing with innovative approaches and new perspectives, as well as practical applications, addressed to a broad range of professionals working in the fields of documentation, surveying, representation, digitisation, visualisation, interpretation and simulation of complex scenarios.

Dr. Daniela Oreni
Dr. Fabrizio Banfi
Dr. Davide Mezzino
Guest Editors

Manuscript Submission Information

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• UAVs digital twin XR-MR-AR-VR scan-to-BIM—BIM projects
• HBIM projects
• BIM-to-FEA
• CoSim
• BEM
• InfraBIM conservation
• management and dissemination of cultural built heritage fault diagnosis energy and structural analysis and costs evaluation virtual museum
• virtual-visual storytelling drone-based and drone-supported solutions

• Digital Twins and Extended Reality: Opportunities and Challenges of Integrated Applications (2nd Edition) in Drones