How does a mixed traffic between autonomous and conventional cars look like in the city? The DLR (The German Aerospace Center) explored two different approaches for left turns at a traffic light.
Within the scope of the project “Digitaler Knoten 4.0” (“digital knot 4.0”), the DLR investigated different solutions for communication between different traffic participants on inner-city crossroads. Project leader Robert Kaul: “The challenge for autonomous and connected driving is the complexity and dynamic of the mixed traffic on inner-city crossroads: autonomous and non-autonomous vehicles encounter bicycles and pedestrians”.
For these new situations at inner-city traffic lights, the DLR and its partners developed two approaches for left-turning vehicles. By connecting the autonomous vehicle and the traffic light, an autonomous left-turn can be performed. The involved research vehicles cooperate cia vehicle-to-vehicle and vehicle-to-infrastructure-communication to quickly and safely find a gap between the oncoming traffic. The “unprotected traffic participants”, like cyclists and pedestrians, are recognized using the data from the sensors of the infrastructure or via their connected smartphones. The autonomous vehicle gets informed via special wifi or network standards.
New traffic light controls with presorting
Furthermore, a novel cooperative concept for crossroad controls for turning was developed. To guarantee a safe way for autonomous and conventional vehicles over the crossroads, a presignaling and presorting in the entrance to the crossroads was designed. Other parties that were involved in the project “Digitaler Knoten 4.0” are AVL Software and Functions, Nordsys, Oecon Products & Services, the Offis – institute for computer science, Schlothauer & Wauer, the technical university of Braunschweig together with the “Niedersächsisches Forschungzentrum Fahrzeugtechnik” as well as Volkswagen.