Applications of Vehicle-to-Infrastructure (V2I) Messaging in Mitigating High-Angle Intersection Collisions in the United States

High-angle intersection crashes are among the most injurious in the U.S. transportation network, often resulting in severe lateral-impact trauma. While strategies like geometric redesign and signal optimization exist, they frequently overlook the behavioral component: drivers approaching intersections at unsafe speeds. Vehicle-to-Infrastructure (V2I) communication technology addresses this gap by delivering real-time, individualized in-vehicle warnings.

However, despite growing interest in connected safety applications, there remains a clear research gap: most prior evaluations rely on simulations or short-duration pilots, leaving limited empirical evidence on how V2I applications such as Red-Light Violation Warning (RLVW) and Pedestrian in Conflict (PEDCONFLICT) influence real-time driver behavior in naturalistic, operational corridors. These applications are not yet commercially available; instead, they exist in pre-commercial form within pilot deployments, making real-world behavioral evaluation essential for informing future large-scale adoption.

This paper synthesizes findings from Phase 2 of the Connected Marysville-Dublin Pilot, involving 144 vehicles instrumented with on-board units (OBUs) operating within a live V2I corridor in Ohio. The study evaluated RLVW and PEDCONFLICT applications, both leveraging Signal Phase and Timing (SPaT) and intersection map (MAP) data transmitted from roadside units (RSUs).

Statistical analysis via Wilcoxon signed-rank testing demonstrated significant behavioral improvements. For RLVW, drivers reduced speeds by 4.80–8.73 mph within 2.5 seconds and 10.61–15.80 mph within 5 seconds post-alert. For PEDCONFLICT, reductions of 1.01–1.55 mph and 2.23–2.42 mph were observed at corresponding intervals. These reductions are functionally significant, particularly regarding pedestrian survivability. Compliance rates improved longitudinally, indicating a sustained behavioral shift.

From a systems perspective, V2I messaging is a scalable mechanism for converting existing infrastructure data into driver behavior change. Unlike vehicle-embedded autonomous systems that are unevenly distributed, V2I alerting functions across all OBU-equipped vehicles in an instrumented corridor, providing a critical path to safety at scale. This paper argues that V2I-enabled intersection applications should be prioritized as public safety infrastructure, comparable to lighting or signal modernization, and provides a robust empirical foundation to support this shift in national safety investment frameworks.