In-Vehicle Sign Systems May Improve Safety When Supplementing Road SignsStatus: CompleteReport Date: 05/24/2016 Summary: The Minnesota Road Fee Test produced several ideas about services that could be delivered to drivers via a smartphone app. This project used a driving simulator to investigate the effectiveness of using the smartphone to display road signs. Tests demonstrated that when the in-vehicle sign system replaced external signs, driver speed and speed variability increased, which would have negative impacts on safety. In conjunction with external signs, however, the system resulted in driver speeds that were comparable to a baseline test, and speed variability decreased slightly, which may improve safety. Final Deliverables: Report #2016-18 Research Summary Related Materials: Related Research: