Digital twin federation for urban mobility assessment: Definition, pillars, and a human-in-the-loop functional architecture

Source abstract

Urban mobility systems face growing challenges. While various smart mobility solutions have been proposed, most existing planning tools were originally designed for infrastructure-related issues. There is still a lack of comprehensive tools for assessing the impact of new service-oriented mobility solutions. Furthermore, Digital Twins (DTs) have been proposed to automate solutions, yet such automation often conflicts with the requirements of human-driven planning in urban mobility systems. To this end, this paper presents a Digital Twin Federation (FedDT) designed for comprehensive urban mobility assessments with human-in-the-loop control. Firstly, a definition of the FedDT concept is established based on four conceptual pillars distinguishing FedDT from existing tools, including physical & digital system exchange, system monitoring & planning, outcome evaluation & immersive experience, and human-in-the-loop control. Then, based on consultations with a consortium of experts, we present a functional FedDT architecture that integrates multilevel simulations with real-time data ingestion, traffic management and optimisation, advanced data analysis, and interactive visualisation. The FedDT concept establishes a human-in-the-loop design for mobility research. This enables iterative, bidirectional data exchange between the physical mobility system and digital replicate, thereby supporting a data-driven decision-making process while ensuring the interests of relevant stakeholders are continuously communicated and integrated into strategic planning. We demonstrate the FedDT through our proof-of-concept case study for reducing the region's private vehicle dependency in Amsterdam, the Netherlands. Overall, this work lays a functional and architectural foundation for deploying FedDT in mobility planning, advancing the technical implementation of integrated digital twin solutions for sustainable urban transport systems.