Using C-ITS for Shockwave Damping and Preventing on Highways

Shockwaves are traffic pulses that mainly propagate upstream of traffic flow; commonly found on highways. The phenomenon is created due to the fact that vehicles move at different speeds and many drivers tend to change their speed abruptly; resulting to a temporary limited length tail. This can be damped or prevented using Connected Intelligent Transportation Systems (C-ITS). It is possible to damp or avoid shockwave formations by transmitting relevant on time messages to drivers, which will suggest optimal driving behaviours. In this direction, a method for damping/avoiding traffic pulses (shockwaves) is developed and presented in detail in this paper. After analyzing traffic data from the Attikes Diadromes S.A. highway, Artificial Neural Networks (ANNs) were developed and trained to detect incidentswhen there is a high probability of shockwave formation. The ANNs were evaluated with real-world data from video analysis. In view of the evaluation, an optimal ANN for detecting shockwaves and an optimal ANN for detecting shockwave forerunners are proposed. The messages to be sent to drivers when detecting such incidents were analyzed. Final messages are proposed based on the available technology and equipment. Next, the C-ITS architecture is developed to support the above services. It was ascertained that the developed ANNs detect shockwaves and shockwave forerunners very efficiently based on specific Key Performance Indicators (KPIs). When the detection ismade, the relevant-messages are transmitted to drivers in real time. The impact of shockwave preventing and damping messages can be tested through pilot activities.