Assessment of In-Vehicle Messages in the Advance Warning Area of a Work Zone

Simulations and field tests have shown that the connected vehicle technologies would not only enhance the mobility and safety of traffic operation, but also possibly reduce fuel consumption and exhaust emissions. So far, there is no consistent evaluation procedure on the perfomances of these in vehicle messages to drivers in work zone area. The objective of this research is to test, compare and develop a warning system to prevent occurring of work zone crashes and reduce vehicle emission. The main purpose of this study is to test and evaluate the different set of warning messages in the advance warning area of a work zone and develop an evaluation system for the warning system from the perspective of speed, acceleration rate, brake positions, lane changing positions, emission and work load. The work load of the three types of warning system is evaluated based on the NASA-TASK Load Index. The application of the mixed audio and image messages was able to reduce the overall vehicle emissions (CO2, CO, HC, and NOx). With the help of the both audio and image messages, drivers tend to recognize the road situation earlier than in the conventional situation and this will have a positively influence on driving safety. Especially, the mixed messages scenario outweights the other two scenarios in speed, acceleration rate, braking positions, emission, and work load.