A study of the scheduling effect on shared autonomous vehicles adoption

Abstract

Adopting the concept of ridesharing, shared autonomous vehicles (SAVs) are introduced to provide low-cost and convenient mobility-on-demand services. Previous studies have investigated the trip purposes and user's characteristics in adopting on-demand ride services and SAVs. However, very little attention has been paid on the traveler's trip making decisions, including departure time choice and mode choice. Hence, this study aims to conduct the Revealed Preference (RP) and Stated Preference (SP) surveys and to develop a joint model of mode and departure time choice to determine the contributing factors affecting traveler’s choice decisions, particularly concerning SAV adoption. Both the RP and SP survey suggest that middle-income travelers with an age range between 20 and 39 years are more likely to adopt SAVs. It was found that the travel time and walking time were the two most significant service attributes in SAV adoption. The increase of 10% of SAV travel time and the introduction of 2 min walking time reduce the SAV adoption by 15% and 90%, respectively. In addition to that, the results suggest that the value of schedule delay early (SDE) is much lower than the value of time and schedule delay late (SDL), as more than 80% of travelers prefer to depart early. These findings can be used to further assist in developing dynamic traffic modeling to aid travel demand management (i.e., congestion charging) that involves SAVs adoption.