Connected Vehicles Program: Driver Performance and Distraction Evaluation for In-vehicle Signing

The Minnesota Department of Transportation (MnDOT) conducted a demonstration project as part of the Connected Vehicles Program to design, build, and test three new software applications to run on a commercially available personal navigation device (PND). The goal of this study was to examine only the in-vehicle signing (IVS) function for four zones and determine the utility and potential distraction associated with this function. The specific zones of interest that were signed on the PND were areas where speed zone changes occurred along the same roadway or for speed changes associated with construction, school and curve zones. A continuous navigation function was provided in two of the three conditions to examine the effect of navigation information alone and multiple sources of information on driving performance. Driving performance measures known to be related to distraction as well as subjective usability and workload measures were used to help identify potential distraction associated with the IVS information. The project identified some driver effects that may occur when using a commercially available navigation device with in-vehicle signing (IVS) information, such as drivers demonstrating higher speeds associated with some of the System On conditions. Overall, distraction effects were small and not consistent across all zones or conditions. The main conclusion drawn from this study was that the IVS information was considered useful by drivers and resulted in few distraction-related effects. The benefit of advance notification likely outweighs any distraction that may be associated with in-vehicle signing of these zones.