# Seeking a Definition of Digital Twins for Construction and Infrastructure Management
## 3 Digital Twins Current State of the Art
### Digital Twin Development Frameworks
The results included detailed materials and lighting that closely matched the input images, and the DTs could be rendered from different viewpoints and lighting setups, highlighting the framework's flexibility and power. NVIDIA Omniverse [35] is a comprehensive open computing platform designed for creating, managing, and operating high-fidelity DTs with real-time simulation capabilities. Leveraging cutting-edge technologies, such as the Universal Scene Description (USD), a framework developed by Pixar, NVIDIA RTX technology for real-time ray tracing, and advanced AI and machine learning capabilities, Omniverse supports detailed 3D visualisation and robust collaboration across various domains. The platform integrates seamlessly with industry-standard tools through Omniverse Connectors, enabling it to ingest and work with diverse data sources, facilitating a unified workflow. Omniverse Nucleus is a core component that enables multiple users to collaborate on the same 3D models and scenes, managing data storage, access controls, and live synchronisation. This ensures that all stakeholders can work with the most current information, enhancing decision-making processes. The platform also includes Omniverse Kit for developing custom applications, Omniverse View for reviewing and interacting with 3D scenes, and Omniverse Create for content creators to build, animate, and render complex 3D scenes. In construction and BIM, Omniverse enhances design and planning processes by enabling real-time collaboration among architects, engineers, and construction professionals. It allows for the creation of highly detailed and interactive DTs of buildings and infrastructure, facilitating virtual walkthroughs, stress tests, and identification of potential issues before actual construction begins. This helps reduce the risk of errors and optimises designs based on the real-time simulations of lighting, material behaviours, and structural responses. For example, implementing Omniverse in a BIM project can reduce design errors by up to 30%, cut project timelines by 20%, and decrease material wastage by 15%. For smart cities, Omniverse enables the creation of DTs for urban infrastructure, such as transportation networks, utilities, and public spaces. These DTs help city planners and managers monitor and optimise the performance of these systems in real-time, improving efficiency and reducing operational costs. For example, a DT for a city's transportation network can simulate traffic flows, identify congestion points, and suggest optimal routing strategies, potentially reducing traffic congestion by up to 25%. Similarly, DTs of utility systems can monitor energy usage, detect leaks, and optimize resource distribution, leading to energy savings of up to 20%. In Industry 4.0 applications, Omniverse supports the creation of DTs for manufacturing processes and industrial equipment. These DTs enable real-time monitoring, predictive maintenance, and optimisation of production workflows. For instance, a DT for a factory floor can simulate different production scenarios, identify bottlenecks, and suggest process improvements to increase efficiency and reduce downtime. Integration with IoT sensors and data streams ensures that DTs are always up to date, reflecting the current state of physical assets. Quantitative benefits in this context include a 15% increase in overall equipment efficiency (OEE), a 10% reduction in unplanned downtime, and a 12% improvement in production throughput. A notable industrial application of NVIDIA Omniverse is its use in developing a DT for the GA/DIII-D tokamak fusion reactor. In collaboration with Princeton University, this DT incorporates AI-driven real-time simulations to model plasma dynamics and control systems, enabling near-real-time experiments and accelerating the development of fusion energy technologies.