Shared-vehicle Mobility-on-demand Systems: a Fleet Operator’s Guide to Rebalancing Empty Vehicles

1 We consider the operation of automated mobility-on-demand systems, whereby users share access to a fleet 2 of self-driving vehicles. In these systems, rebalancing, the process by which the supply of empty vehicles is 3 periodically realigned with the demand for transport, is carried out by a fleet operator. Where much of the 4 rebalancing literature skews to the theoretical or simulation-based, we considering shared mobility systems 5 from the perspective of the fleet operator. We test, via simulations, how key performance metrics vary as a 6 function of fleet size and rebalancing policy using rental data from car2go, a free-floating carsharing service 7 operating in markets across Europe and North America. Results reveal that rebalancing can dramatically 8 reduce the number of customer walk aways, even for relatively small fleet sizes. A framework is provided 9 to assess what fleet size is a appropriate for a city factoring in the cost of vehicles, customer walk aways, 10 and the added expense of moving empty vehicles. 1