Olli, the autonomous bus, is pictured in front of the Tennessee State Capitol building in Nashville during “UT Day on the Hill” in February. Photo by University of Tennessee System.
The transportation research faculty, consisting of Assistant Professor Candace Brakewood, along with Professor Chris Cherry and Professor Lee Han, are on the forefront of examining the viability of fully autonomous buses. Together with graduate research assistants Mojdeh Azad and Nima Hoseinzadeh, they published their findings in the Journal of Advanced Transportation.
Automated vehicle (AV) technology has grown explosively in recent years and has, therefore, been widely studied by many researchers in related fields. These research studies have been conducted in different contexts, including AV technology and its impacts on mobility, safety, the environment, and the economy.
However, they have been focused largely on personal or on-demand vehicles, despite the growing use of automation technology in the transit industry. Therefore, the group’s paper focused on fully autonomous buses to fill this emerging gap in the literature.
After a review of the titles and abstracts of the found peer-reviewed journal articles, conference proceedings, and reports from large ongoing federal and governmental autonomous bus projects in academic search engines, a total of 40 articles were deemed relevant to this review.
First, the UT team found that this research topic varies by geography. While there were a small number of projects and demonstrations in the US, European manufacturers had been partnering in many on-going projects.
Second, these studies can be categorized into five main themes: “user acceptance,” “technology development,” “social and economic aspects,” “safety,” and “policies, regulations, and legal issues,” sorted by the number of studies in each theme.
It is important to note that these themes are interrelated; technology development is associated with potential increases in safety and reductions in operating costs. However, user acceptance and perceived safety and security is generally found to be associated with having staff on board, which is associated with operating costs.
Additionally, several gaps were apparent in the literature, yet to be studied by researchers. For example, the studies highlight the need for policymakers and experts to develop a systematic framework for legal issues and liability concerns.
Similarly, the effects on the job market need to be thoroughly studied. Furthermore, topics such as larger vehicle sizes (e.g bus rapid transit), transit network redesigns, and alternative fuels, need more attention in future studies.
This research was supported in part by a 2018-2019 Community Research Seed Award from the Office of Research and Engagement at the University of Tennessee, Knoxville.