A modular, adaptive, and autonomous transit system (MAATS): An in-motion transfer strategy and performance evaluation in urban grid transit networks

• Published in: Transportation research. Part A, Policy and practice Vol. 151; pp. 81 - 98
• Main Authors: Wu, Jiaming, Kulcsár, Balázs, Selpi, Qu, Xiaobo
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2021
• Subjects: Autonomous modular bus; Nonlinear programming; Public transit system; Public transit system; Autonomous modular bus; Nonlinear programming
• ISSN: 0965-8564; 1879-2375; 1879-2375
• DOI: 10.1016/j.tra.2021.07.005

•A modular, adaptive, and autonomous transit system (MAATS) can be adaptive to dynamic traffic demands.•A bi-level optimization method is developed to minimize the number of passenger transfers during in-motion transfer.•Experiments show the system is sensitive to demand ratios.•Potential implementations and practices are extensively discussed. Dynamic traffic demand has been a longstanding challenge for the conventional transit system design and operation. The recent development of autonomous vehicles (AVs) makes it increasingly realistic to develop the next generation of transportation systems with the potential to improve operational performance and flexibility. In this study, we propose an innovative transit system with autonomous modular buses (AMBs) that is adaptive to dynamic traffic demands and not restricted to fixed routes and timetables. A unique transfer operation, termed as “in-motion transfer”, is introduced in this paper to transfer passengers between coupled modular buses in motion. A two-stage model is developed to facilitate in-motion transfer operations in optimally designing passenger transfer plans and AMB trajectories at intersections. In the proposed AMB system, all passengers can travel in the shortest path smoothly without having to actually alight and transfer between different bus lines. Numerical experiments demonstrate that the proposed transit system results in shorter travel time and a significantly reduced average number of transfers. While enjoying the above-mentioned benefits, the modular, adaptive, and autonomous transit system (MAATS) does not impose substantially higher energy consumption in comparison to the conventional bus system.