In-Vehicle Work Zone Messages-Examining Signing Options for Improving Safe Driving Behaviors in Work Zones - MnDOT

Project summary:

Highway work zones require drivers to reduce speed and be aware of work crews, lane closures, traffic backups, construction equipment and other potential hazards on the roadway. Transportation departments have long employed stationary warning signs, sometimes supplemented by Portable Changeable Message Signs (PCMS) to alert drivers to upcoming construction projects. However, some previous studies have indicated that stationary warning signs are not always effective.  

The researchers conducted literature reviews and 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 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.