Modeling the Mixed-Service Fleet Problem of Shared-Use Autonomous Mobility Systems for On-Demand Ridesourcing and Carsharing With Reservations

Abstract

This paper studies a mixed-service operation of shared-use autonomous mobility systems (SAMS) where customers can request rides either immediately or through reservations and use the vehicle for a point-to-point service or a time-slot-based rental service, respectively. Three autonomous-vehicle-to-user assignment strategies are presented: a first-come-first-served strategy and two optimization-based (bipartite matching) strategies. The mathematical formulations attempt to achieve a good trade-off between the wait times of reservation-based users and on-demand users, while minimizing overall empty fleet miles. A case study in Chicago is presented using taxi data, and the combined mixed-service fleet operation is compared with a case with two separate operations: one for an on-demand point-to-point service and one for a reservation-based time-slot rental service. Results show that a combined mixed-service operation can provide a more balanced service than the case with two separate operations with respect to the key performance measures of wait time and empty fleet miles.