Digital Twin-Based Cooperative Driving at Roundabouts for Connected and Automated Vehicles

A digital twin is a digital replica of a physical entity in the real world. As an emerging technology, it has been widely used in various industries. Vehicle-to-everything (V2X) communications enable connected and automated vehicles (CAVs) to communicate with other entities (other vehicles, infrastructures, pedestrians, etc.) in the transportation environment to achieve cooperative driving maneuvers. In this paper, a digital twin-based cooperative driving system is developed for CAVs to enhance performance in terms of sustainability, efficiency, and safety at roundabouts. A consensus motion control algorithm is developed in the system to compute the referenced motion of CAVs, integrated with other supplementary modules such as map matching, path query, and sequencing. Specifically, digital twins of CAVs and a roundabout at the Purdue University campus are constructed in the Unity game engine, validating the proposed system with simulation experiments. When compared to human driving behavior, the proposed cooperative driving system shows several notable improvements: a remarkable 58% reduction in emissions and a 64% reduction in speed variance, among other savings in energy consumption and travel time. The video recording of this study can be watched at https://youtu.be/pA13qd201MI