Fully Autonomous Buses: A Literature Review and Future Research Directions
Table 4
Key studies on the social and economic aspects of autonomous buses.
Author(s) (year)
Type
Location
Methods
Key findings
Sessa et al. (2015)
Report
Europe, United States, and Asia∗
Stated preference survey and expert workshop (, from academia, automotive industry, city and local authorities)
(i) Two extreme scenarios (“automated private car ownership vs. automated car-fleet sharing”) and four different urban typologies (“urban sprawl, city network, small compact city, and rural/tourist areas”) were considered in this online survey of experts
(ii) Economic impacts (e.g., personal trip costs, fines, insurance) are expected to be mostly positive except for possible employment impacts
(iii) Environmental impacts (e.g., energy and emissions, urban requalification, land saving) are expected to improve
(iv) Transportation impacts in terms of road capacity and comfort and convenience are mostly positive
Lam et al. (2016)
Journal
Australia
Simulation (employing AV in public transportation network)
(i) Journey time significantly affects the waiting time, cost, and reliability of the system
Piao et al. (2016)
Conference proceeding
Europe∗
Survey (, La Rochelle, France)
(i) Survey results show the largest benefit from the passenger perspective is lower bus fares due to reduced driver costs
Polzin (2016)
White paper
United States
Position paper/expert opinion
(i) Autonomous buses can lead to restructuring of public transport systems by providing services based on riders’ needs (e.g., paratransit service)
(ii) Technology related factors such as flexibility, safety, and reliability might affect travel decisions
Executive Office of the President, The White House (2016)
Report
United States
Macroeconomic and labour analysis
(i) Up to 100% replacement of bus driving jobs due to automation is likely to happen
Bösch et al. (2017b)
Conference proceeding (TRB)
Europe
Simulation (policy combinations in an AV based transport system)
(i) Different AV based scenarios are likely to increase VMT and decrease accessibility
(ii) Lower fares for autonomous buses could lead to higher accessibility, fewer cars, and lower VMT
(iii) One of preferred policy scenarios was free autonomous bus and autonomous motorized individual transport, which increased average accessibility by 0.5% and reduced total system VMT by 1%
Bösch et al. (2017a)
Journal
Europe
Cost analysis
(i) The current form of public transportation will remain competitive only if demand is sufficient, e.g., in dense urban areas
(ii) Autonomous buses could be competitive in dense urban areas where the price of public transportation is lower than autonomous taxis
Cedar et al. (2018)
Conference proceeding (TRB)
Europe and New Zealand
Simulation model (time and cost models for Paris Charles de Gaulle Airport, France, and the Auckland Airport, New Zealand)
(i) Costs can be reduced by 20–64% if future systems are comprised of 75–100% autonomous public transport vehicles
Cuellar et al. (2018)
Conference proceeding (TRB)
United States
Interviews, Case studies, and Expert workshop
(i) Different categories of disabilities were considered, such as the visually impaired and those with hearing impairments
(ii) Several services and technologies were considered that can support system functions, such as speech to text
(iii) Use cases were developed with three parts: requesting an autonomous shuttle, boarding the autonomous shuttle, and navigating the shuttle
Lutin (2018)
Journal
United States
Position paper
(i) Autonomy can benefit the transit industry if they concentrate resources in areas where additional automobile traffic and parking would be costly. However, it might not benefit the transit industry in areas where transit load factors are too low
(ii) Autonomous buses can improve paratransit service and reduce operating costs, which is almost 10 times more than the operating cost per transit trip on fixed route services ($34.43 compared to $3.68, data from 2014)
Quarles et al. (2018)
Conference proceeding (TRB)
United States
Life-cycle cost analysis
(i) Electric and fully autonomous buses would be life-cycle cost-competitive with diesel-powered buses at a faster rate than electric buses due to reductions in driver costs
Sinner et al. (2018)
Conference proceeding (TRB)
Europe
Cost model (Zug, Switzerland)
(i) Automation can affect transit network design parameters (such as accessibility, direct connections, and frequency), which would result in cost savings for the operator and the public sector
(ii) Automation can result in a savings of 50–60% of system-wide bus operating costs
Zhang et al. (2019)
Journal
Europe and Australia
Cost model (values from Australia Transport Council)
(i) The authors developed a cost model for waiting, riding, operating, and capital costs for three types of bus services (conventional, semi-autonomous, and fully autonomous)
(ii) Fully autonomous buses could reduce operations and waiting costs, even though they may have additional capital costs
(iii) Fully autonomous bus speeds need to be closer to conventional buses (higher)