V2H Communication System Research Results documents a National Project supported by Korea’s Ministry of Land, Infrastructure and Transport conducted across three phases from 2021 to 2026. The research develops vehicle-to-human communication technology for autonomous driving systems through study of communication cases, validation of V2H elements, technology development, and road demonstrations. Survey findings indicate hybrid projection and display approaches achieve 77.7% positive response rates. Trust in autonomous vehicles increased from 24.0% to 41.5%, and safety perception improved from 21.6% to 37.3%. Projection messages reduce pedestrian crossing decision time by 3.64 seconds and ensure 100% crossing decisions with yielding messages across all demographics. Cyan-colored text-based messaging demonstrates superior visibility and user preference ratings of 3.9 to 4.2 on a 5-point scale compared to symbol-based formats.