conference paper

Sharing is caring: Dynamic autonomous vehicle fleet operations under demand surges

Proceedings of the 97th annual meeting of the transportation research board

Publication Date

January 1, 2018

Author(s)

Michael Hyland, Hani Mahmassani

Abstract

Given the emergence and growth of ridesourcing companies, the forthcoming introduction of fully- autonomous vehicles (AVs), and the projected positive impact of AVs on the growth of mobility services, this paper aims to analyze the operational efficiency of two on-demand AV-enabled mobility services (AVeMSs). Specifically, the study compares an AV-enabled shared-ride service, with an AV-enabled traditional ridesourcing (i.e. no shared-rides) service, in terms of handling demand surges, when fleet size is fixed. The authors hypothesize that shared-ride service will significantly outperform traditional ridesourcing service because as demand increases with shared-ride service, the number of feasible shared-ride opportunities increases, effectively increasing the service rate of the shared-ride fleet. To test this hypothesis, the authors employ a dynamic agent-based simulation of travelers, AVs, and an AV fleet operator. The underlying AV fleet control problem is highly-dynamic and stochastic, as traveler requests are unknown to the fleet operator a priori. To solve the dynamic and stochastic optimization problem, the AV fleet operator repeatedly re-solves an online AV-traveler assignment problem based on the current state the system. The simulation results illustrate that under various experimental settings, shared-ride service significantly outperforms ridesourcing service in terms of handling demand surges. At low demand levels, traveler wait times are similar for shared-ride and ridesourcing services. However, as demand increases, average traveler wait times increase more rapidly under ridesourcing service. The results suggest shared-ride service allows fleet operators to better handle demand surges.

Suggested Citation
Michael F. Hyland and Hani S. Mahmassani (2018) “Sharing is caring: Dynamic autonomous vehicle fleet operations under demand surges”, in Proceedings of the 97th annual meeting of the transportation research board, p. 16p.