Integration of extended reality technologies in transportation systems: A bibliometric analysis and review of emerging trends, challenges, and future research

• A bibliometric review of 283 studies (2014–2024) explores XR in transportation. • Key themes: AV validation, pedestrian safety, AR navigation, traffic simulation. • USA, Germany, and China dominate XR outputs with growing interdisciplinary work. • Major gaps: ecological validity, demographics, cybersecurity, real-world trials. • Future XR research must stress scalability, cognition, ethics, and ecosystems. The rapid digital transformation of transportation systems has elevated Extended Reality (XR) technologies—including Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR)—as critical tools. XR improves safety, optimizes mobility, and enhances human-machine interaction.This study presents a bibliometric analysis and thematic review of XR research in transportation. We analyzed 283 Scopus-indexed publications from 2014 to 2024 using Bibliometrix, VOSviewer, and Python-based libraries. The results show an annual publication growth rate of 18.15%. Cornell University, the University of Glasgow, and Delft University of Technology emerged as leading institutional contributors. National leadership was dominated by the United States, Germany, and China.Thematic mapping identified key areas such as autonomous vehicle validation, pedestrian-AV interaction, AI-driven traffic simulation, immersive driver training, and AR navigation for rail and maritime transport. Keyword analysis emphasized research focuses including Virtual Reality, Augmented Reality, Autonomous Vehicles, Pedestrian Safety, Mixed Reality, Traffic Simulation, and Human Factors.Despite this progress, significant challenges persist. Studies often lack ecological validity, demographic diversity, scalability, cybersecurity resilience, and ethical transparency. Most XR applications remain confined to laboratory settings with limited real-world validation or cross-cultural generalizability.To address these gaps, we propose integrated frameworks and a strategic research agenda. We emphasize ecological realism, cognitive-adaptive XR designs, interdisciplinary collaboration, and ethical governance.This study consolidates existing knowledge and outlines future research directions. XR is positioned as a transformative and human-centered technology, crucial for advancing safer, smarter, and more inclusive transportation ecosystems.