To park or to share your autonomous vehicle?

With the ability to drive autonomously during trips and park themselves, autonomous vehicles (AVs) are anticipated to revolutionize future mobility. How AVs interact with people and transform travel behavior patterns (mobility paradigm shift) is expected to be a “game changer”. This paper investigates an innovative future mobility paradigm where private-AV owners can share their vehicles on a mobility service platform when not in use. We develop tractable models to characterize the travel, parking, and vehicle-sharing choices of AV users, optimize operation strategies of the mobility service platform considering AV sharing, and evaluate their system-wide impacts. In particular, given the operation strategies of the mobility service platform, we formulate the system equilibrium that includes the AV owners’ choice equilibrium and the mobility service market equilibrium. We consider two different business formats for platform operator (namely reselling and commissioning) and three types of AV owners (risk-neutral, risk-averse or risk-seeking). Subject to the system equilibrium, we examine the pricing and fleet sizing strategies of the platform to achieve either profit-maximization or social welfare-maximization. Our analysis explores the impacts of introducing the AV sharing scheme on AV owners, mobility service operator and users, and social welfare. It shows that introducing the AV sharing scheme has the potential to create a win-win-win outcome for AV owners, mobility service operator, and users, with an overall improvement in social welfare. Moreover, both a social welfare-maximizing operator and a profit-maximizing operator may achieve a win-win-win outcome under certain conditions. With risk-averse AV owners, the reselling format proves to be superior to the commissioning format; with risk-seeking AV owners, the commissioning format will outperform the reselling format; while with risk-neutral AV owners, both formats can yield identical platform profit and social welfare. Numerical examples are presented to illustrate the analytical results and provide a deeper understanding of the potential implications of AV sharing.