Cooperation Behavior of Drivers at Inner City Deadlock-Situations

In urban traffic, there are several situations in which the right of way is not regulated. For automated vehicles in mixed traffic to show behavior that is considered acceptable by all parties, the cooperation behavior of drivers in these situations must be understood. An observational study identified several behaviors in these situations at equal narrow passages and T-intersections that can be classified as offensive and defensive. These behaviors were tested in an experiment whether they can communicate the intention to drive or to stop. Drivers respond to defensive behaviors of the cooperation partner by continuing to drive, and stopping when the behavior is offensive. In the equal narrow passage, drivers felt safest when they drove first, whereas at the T-intersection, drivers felt safest when the cooperation partner drove first. In further experiments, it was shown that at T-intersections the entry position has an influence on whether drivers drive first or stop. Pedestrians or other traffic do not have an influence on the behavior. However, if drivers follow a vehicle that is driving ahead of them, they drive first through the deadlock situation. Recommendations for the behavior of automated vehicles in these situations are derived from the findings of the studies.