In-Vehicle Work Zone Messages

Work zones present an increased risk to drivers and the work crew. To mitigate these risks, this study investigated the potential effects of in-vehicle messages to communicate work zone events to the driver. The researchers conducted literature reviews on risks imposed by work zones, along with design guidelines for any in-vehicle messaging system. The researchers then conducted a work zone safety survey to illustrate driver attitudes in Minnesota toward work zones, along with smartphone use and in-vehicle messages through smartphones. The survey found that a significant number of drivers make use of smartphones in the automobile, and they placed these smartphones in various locations throughout the vehicle. The survey was followed by a driving simulation study that tested drivers in two different types of work zones. Participants drove through these work zones three times, each with different messaging interfaces to communicate hazardous events to the driver. The interfaces included a roadside, portable changeable message sign, a smartphone presenting only auditory messages, and a smartphone presenting audio-visual messages. There was better driving performance on key metrics including speed deviation and lane deviation for the in-vehicle message conditions relative to the roadside signs. Furthermore, drivers reported significantly less mental workload and better usability, work zone event recall, and eye gaze behavior for the in-vehicle conditions relative to the roadside sign condition.