Abstract
Keywords - traffic management, traffic information, driver assistance system, intervehicle communication, traffic-optimized cruise control, vehicle data analysisRoad works are already a significant cause of traffic congestion today. The real capacity of the road network will thereby increasingly be determined by road works. Due to the condition of the roads and the disproportionate rise in wear from heavy goods vehicles, a rise in road works across the national road network is to be expected. Today the traffic information is often not up-to-date, inaccurate and not relevant for drivers special route. Furthermore traffic simulations have shown a positive influence of traffic-optimized driving behaviour on the formation of traffic congestion.
Within the national research initiative AKTIV (adaptive and co-operative technologies for intelligent traffic), which is promoted by the Federal Ministry for Industry and Technology (BMWi), new technologies for road traffic optimization and information systems are identified. The Traffic Guard is a driver assistance and information system which combines both the precise driver information about traffic situation in the surrounding of the vehicle and the traffic-optimized driving behaviour in several traffic situations.
With means of the Adaptive Cruise Control (ACC) and special traffic-related driving strategies we realized the Traffic Guard in a test vehicle. The information of the vehicle surrounding (e. g. velocity, traffic density) come both from on-board sensors and inter-vehicle and vehicle-to-infrastructure communication (C2C, C2I). Also information from the road operator is used (e. g. position of speed limits and on-ramps). Road Side Units (RSU) in the range of the road work support the system concerning the communication and the application. It receives data from the vehicle which passed the zone, identifies the road geometry and the traffic situation over the course of the road and sends the information to vehicles facing the situation.
A part of the information is displayed to the driver to inform about the traffic situation and road geometry within the next kilometres. A well arranged HMI shows a 3D-view of the imminent road section with additional information the driver is interested in like length of traffic congestion and the time it will take him.
From the receipt of the vehicle data to the display of the essential and precise information a lot of interpretation steps are required. To identify the run of the road with the number of lanes we use the trajectories of the vehicles. For the identification of the traffic situation we analyze the spatiotemporal distribution of velocities in the relevant zone.