Urban Digital-Twin Planning for Sustainable Smart Cities: System Architecture, Preliminary Experiments, and Open Challenges

A Digital Twin (DT) is a digital representation of a physical object, offering unique features such as object mirroring, object relation, data availability, and user interaction. In this paper, we discuss the challenges of deploying urban infrastructure for DT-enabled smart city applications, such as air-quality-aware navigation and traffic management, which aim to improve citizens' quality of life and assist policymakers' decision-making. We refer to this research problem as urban DT planning, with the core objective of enhancing the interoperability and scalability of geolocation- and capability-diverse hardware and software by leveraging modern middleware approaches. Our explorations consist of the following three steps. First, we present our perspective on urban DT planning and propose a general, layered DT architecture. Second, we share our preliminary experiments involving a micro wind turbine using commercial (Microsoft Azure) and open-source (Eclipse) DT platforms. Finally, we conclude the paper with open challenges that need to be studied to achieve the ultimate goal of sustainable smart cities. These challenges are intended to inspire future research on sustainable urban DT planning and encourage the broader adoption of DT-enabled smart city applications.