Traffic jam dissipation capability of human drivers in comparison to intelligently controlled vehicles

Traffic jams are a regular annoyance on today’s roads, resulting in longer travel times, higher air pollution and more stressed traffic participants. It has previously been shown that traffic jams do not only occur following a dedicated event, such as road works or accidents, but may also form randomly if traffic density and average velocity rise over a critical threshold. A typical proving ground scenario to study human and automated vehicle behavior in these spontaneous traffic jams is a single-lane, closed ring road, fully populated by vehicles. The simplicity of this scenario allows for the detailed study of traffic jam dissipation techniques and related driving behavior, and for the comparison of human drivers with automated vehicles. In an interactive driving simulator study, thirty human drivers and several automated intelligent controller variants were tasked with dissipating an occurring traffic jam. It demonstrated markedly different strategies employed by human drivers and identified successful and maladaptive approaches. By comparison, automated controllers were more consistently able to resolve traffic jams, allowing for relatively high average velocities during the obstruction. However, the total time the intelligent controllers needed to stabilize the traffic situation was only average compared to the human drivers. In a future faced with mixed traffic involving both automated and human controlled vehicles in complex traffic scenarios, understanding the diverse approaches to the dissipation of traffic jams is crucial for evolving traffic management systems.