Mitigating driver confusion and aggression in mixed traffic: Effects of V2V communication and driving style.

Drivers in human-driven vehicles (HDVs) can get confused when encountering automated vehicles (AVs) driving so defensively that their behavior differs from what human drivers actually expect. The confusion may potentially provoke aggression toward AVs and jeopardize traffic safety. This study investigated whether a vehicle-to-vehicle (V2V) communication system can help mitigate HDV drivers' confusion and aggressive driving behavior toward AVs in HDV-AV interaction, considering the driving styles of both HDV drivers and AVs. Forty-eight participants, classified by driving style (defensive, moderate, or aggressive), completed a driving simulator experiment in two blocks (V2V-off vs. V2V-on). In each block, they interacted with aggressive AVs and defensive AVs, respectively. Behavioral indicators of confusion and aggressive driving behavior were recorded from the driving simulator, and subjective confusion was measured via questionnaires. The results showed that compared to the V2V-off condition, interaction under the V2V-on condition significantly reduced HDV drivers' confusion and mitigated aggressive driving behavior during the interaction. Aggressive AVs that asserted their right-of-way elicited less confusion among HDV drivers than defensive AVs that were more inclined to yield to other vehicles. These findings suggest that V2V communication and aggressive yet rule-compliant AV driving styles help reduce driver confusion and aggressive driving behavior, thereby improving HDV drivers' experiences and reducing conflict risk during HDV-AV negotiations.