Investigating factors influencing takeover performance in conditionally automated driving: The role of uncertainty communication

Tekkesinoglu, Sule; Kunze, Lars

Abstract

Safe transition following a Takeover Request (ToR) in Level 3 automated driving requires a high situational awareness, which is influenced by traffic complexity, non-driving-related tasks (NDRTs), and communication strategies. These factors are often studied in isolation, focusing on individual elements such as the effects of NDRT, ToR timing, or alert design. However, a holistic investigation that considers the interdependencies of these factors is lacking. This study provides a comprehensive analysis of the human, environmental, situational, and vehicle-system factors affecting takeover performance, examining their interactions under conditions with and without uncertainty communication. We explored the effectiveness of adaptive uncertainty communication-preparatory alert prior to the ToR-in enhancing driver readiness and response in time-constrained scenarios. A simulation-based online study (N = 60) was conducted, where participants experienced multimodal takeover alerts across diverse scenarios involving varying traffic conditions and NDRT types. Our findings indicate that uncertainty communication mitigated the impact of human factors such as trust, fatigue, and stress. Without such communication, these effects were more pronounced. It also improved participants' understanding of the ToR reason and perceived appropriateness of ToR timing. While task-switching remained a challenge under high distraction, uncertainty communication modestly reduced task-switching difficulty. Overall, scenarios involving the preparatory alert received higher ratings for notice time, preparedness, and alert effectiveness. Drawing on insights from the correlation analysis across all factors, we outline key challenges and directions for future research undertaking adaptive alert strategies that support real-time mode transitions.

• Journal Article Type: Article
• Acceptance Date: Sep 9, 2025
• Online Publication Date: Sep 12, 2025
• Publication Date: Sep 25, 2025
• Deposit Date: Sep 27, 2025
• Publicly Available Date: Sep 29, 2025
• Journal: IEEE Open Journal of Intelligent Transportation Systems
• Electronic ISSN: 2687-7813
• Publisher: Institute of Electrical and Electronics Engineers (IEEE)
• Peer Reviewed: Peer Reviewed
• Volume: 6
• Pages: 1245 - 1264
• DOI: https://doi.org/10.1109/OJITS.2025.3609629
• Keywords: INDEX TERMS Conditionally automated driving; Feedback communication; Human factors; Takeover request; Uncertainty communication
• Public URL: https://uwe-repository.worktribe.com/output/15092305
• Publisher URL: https://ieeexplore.ieee.org/document/11162601