Quantifying Effectiveness and Impacts of Digital Message Signs on Traffic Flow

As Michigan Department of Transportation (MDOT) continues to invest in the advancement of intelligent transportation systems, the use of different types of digital message signs for various applications, such as variable speed limit, real time travel delay information, detour options, queue warning signs, work zone signs, etc., remain prevalent. A significant budget is required to invest in the deployment, operation, and maintenance on each of these technologies. Therefore, effective applications need to be selected based on the impacts that they have on traffic flow tailored to the geographic area. A major factor in the effectiveness evaluation of these signs is the compliance rate among travelers and the diversion influenced by motorist communications. Another factor which can influence motorist compliance are the installation details of these technologies, such as the vertical and longitudinal locations, size, font, color, light intensity, etc. Sign applications can also be influenced differently at various locations such as urban, suburban, and rural areas. These variables will need to be assessed qualitatively regarding the impacts of sign applications on traffic based on location. Travel is required as part of the study with time at field and MDOT Operation Center locations.