Urban Mobility Dynamics in the Realm of Autonomous Shuttles on Dedicated Lanes: A Microscopic Synthesis

The growing interest in utilizing autonomous vehicles (AVs) for public transportation is increasingly evident in urban areas, and numerous locations worldwide have set up demonstration sites to test autonomous shuttles (ASs). However, there is a significant necessity to investigate the future traffic operational performance resulting from such services, in addition to the user behavior-based studies conducted during pilot projects. In this paper, an experimental approach is presented using a microsimulation environment to develop the traffic model with dedicated AS lanes. The approach examines different combinations of conventional vehicles (CVs), ASs, AV driving logics, and geometric modifications required to accommodate the AS service. The traffic performance of the network is evaluated using five measures of effectiveness (MoEs) at various market penetration rates (MPRs). The results reveal that the cautious driving behavior poses challenges primarily during the early stages of the MPR, and the same holds true at very high MPRs or if this driving behavior is sustained for an extended period. Thus, it is advisable to transition towards adopting higher driving logics (Normal and Aggressive), which exhibit highly promising results in meeting expectations. The trend of the results clearly indicates that utilizing dedicated lanes for AS buses is a potential option for integrating the emerging mobility solution into the current transportation system. The findings of this study are of significant importance, as they offer valuable quantitative insights that enable key stakeholders to make well-informed decisions on AS deployment.