Speed Warning System Tested in Minnesota Reduces Vehicle Speed by up to 10 Percent on Curved Road Segments. METHODOLOGY The test system was designed so that drivers would receive alerts from the smartphone app as they pass through three checkpoints when approaching curves on the test track. Checkpoint 1:… Content type Benefit Date Posted 11/23/2021 Taxonomy (ARC-IT) In-Vehicle Signage (TI07), Curve Speed Warning (VS05) Geolocation links St. Cloud, Minnesota, United States