Optimizing dynamic switching between fixed and flexible transit services with an idle-vehicle relocation strategy and reductions in emissions

Document Type

Journal Article

Publication Date


Subject Area

mode - demand responsive transit, mode - bus, place - north america, place - urban, infrastructure - fleet management, technology - emissions, planning - methods


Markov decision process (MDP), Fixed-route transit, Flexible-route transit, Pre-positioning of idle vehicles, vehicle miles traveled (VMT)


A novel approach to dynamic switching service design based on a new queuing approximation formulation is introduced to systematically control conventional buses and enable provision of flexible on-demand mobility services. This new approach guides smart vehicles in a service area that needs last mile transit services via either traditional buses, which provide fixed-route services, or flexible-route on-demand mobility services. We also include dynamic pre-positioning of idle vehicles in anticipation of new customer arrivals, and relocation of vehicles to rebalance the use of vehicles in the system, which can have a sizable effect on energy and environmental conservation. Using a New York City transit dataset, the proposed strategy for non-myopic switching between flexible-route and fixed-route service and re-positioning of idle vehicles improves social welfare by up to 32%, while the impact of the proposed strategy on vehicle miles traveled is shown to be as high as 53% over that of the current transit service.


Permission to publish the abstract has been given by Elsevier, copyright remains with them.


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