The Interplay Between Fleet Size, Level-of-Service and Empty Vehicle Repositioning Strategies in Large-Scale, Shared-Ride Autonomous Taxi Mobility-on-Demand Scenarios
The widespread adoption of autonomous vehicles could lead to a shift from individual vehicle ownership to a system of shared-ride autonomous taxis (aTaxis) operated in fleets. Explored are large-scale systems where all non-walking person-trip demand is served by aTaxis. Using New Jersey as a case study, this work looks at the implications that various empty vehicle repositioning strategies have on fleet size, empty vehicle miles, and level-of-service provided. Results show that repositioning vehicles locally during the day can decrease the needed fleet size significantly while still providing a high level-of-service. The largest fleet, consisting of 3,232,096 aTaxis, is needed if repositioning is done once per day in the early morning to position the aTaxis to serve an exact repeat of yesterday?s ?typical day? (of 30,125,587 individual person-trips). This incurs an empty vehicle repositioning cost that is 8.3% of the total loaded vehicle miles traveled. At the smallest theoretical fleet size of 821,646, all aTaxis available are occupied at some point during the day. Because repositioning cannot take place instantaneously, this fleet cannot provide an adequate level-of-service during peak times. For the smallest practical fleet size analyzed of 1,069,782 vehicles (10% between the largest fleet and the theoretical minimum), 96.8% of passengers are served within 5 minutes beyond the advertised level-of-service while incurring an empty repositioning cost of only 5.2% of total loaded vehicle miles. With one central fleet operator, a significantly smaller fleet of aTaxis can deliver on-demand mobility to all of New Jersey that is equivalent to, if not better than, the mobility delivered by 6,874,100 vehicles registered in New Jersey in 2014 (not all of which are operated on any given day).
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Supplemental Notes:
- This paper was sponsored by TRB committee AP040 Standing Committee on Automated Transit Systems.
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Corporate Authors:
500 Fifth Street, NW
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Authors:
- Zhu, Shirley
- Kornhauser, Alain
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Conference:
- Transportation Research Board 96th Annual Meeting
- Location: Washington DC, United States
- Date: 2017-1-8 to 2017-1-12
- Date: 2017
Language
- English
Media Info
- Media Type: Digital/other
- Features: Figures; References; Tables;
- Pagination: 15p
- Monograph Title: TRB 96th Annual Meeting Compendium of Papers
Subject/Index Terms
- TRT Terms: Case studies; Demand responsive transportation; Intelligent vehicles; Level of service; Mobility; Ridesharing; Routes and routing; Taxi services; Vehicle fleets
- Geographic Terms: New Jersey
- Subject Areas: Operations and Traffic Management; Planning and Forecasting; Public Transportation; Vehicles and Equipment;
Filing Info
- Accession Number: 01624258
- Record Type: Publication
- Report/Paper Numbers: 17-05960
- Files: TRIS, TRB, ATRI
- Created Date: Jan 27 2017 9:28AM