About the research
Transportation agencies spend significant portions of their annual budgets to facilitate safe and efficient travel under hazardous weather conditions. This project is a continuation of the project titled Evaluation of Dynamic Advisory Messaging – Phase I that further supports the Iowa Department of Transportation’s (DOT’s) desire to explore how a dynamic advisory system might work within the Iowa DOT Intelligent Transportation Systems (ITS) platform through data obtained for a segment of I-35.
The evaluation contrasted sensor-driven messages (dynamically derived), based on an algorithm developed in Phase I, with measurements of speed data under various winter weather conditions. In addition, other data inputs such as friction sensors were considered by comparing their outputs to traffic sensor data.
Overall, the dynamic advisory messaging system performed as desired by providing alerts of deteriorating conditions during severe winter events. The system can also identify other sources of traffic impacts outside of winter weather conditions, such as slow speeds that occur as a result of an incident. The signature of winter events was present in both the friction and traffic data; however, the friction data at times had more latency. This may be due to the different data reporting frequencies. The findings showed that speed sensors provided awareness of winter events as well as other non-weather related traffic slowdowns.