The morning commute problem with endogenous shared autonomous vehicle penetration and parking space constraint

Morning commuting trips commonly involve a number of transportation modes and departure times. This study extends the standard bottleneck model by considering both regular and shared autonomous vehicles with and without parking space constraint, taking into account the travel time-dependent fuel cost that is associated with each vehicle. In this study the parking space constraint has no effect on shared autonomous vehicles and only commuters who share autonomous vehicles exhibit ridesharing behavior, differing from those utilizing regular vehicles. The dynamic departure patterns and endogenous penetration rates associated with shared autonomous vehicles are determined with respect to parking capacity. Analytical results not only provide several important propositions, but also include the optimal solutions for parking capacity and ridesharing occupancy from the perspective of the system optimum in terms of various indicators, under which parking capacity is a binding constraint, and the first shared autonomous vehicle arrives at the bottleneck as the last regular vehicle leaves. This work is expected not only to motivate related research, but also to promote the development of new strategies and methods for allocating a limited number of parking spaces and regulating the travel behavior of commuters in urban areas.