Simulation of fixed versus on-demand station-based feeder operations. (November 2021)

• Record Type: Journal Article
• Authors: Leffler, David; Burghout, Wilco; Jenelius, Erik; Cats, Oded
• Is Part Of: Transportation research. Volume 132(2021)
• Publication Date: 2021-11
• Subjects: Demand-responsive transit -- Feeder -- Simulation -- Automated vehicles -- Reliability -- Equity; Transportation -- Periodicals; Transportation -- Technological innovations -- Periodicals; 388.011
• DOI: 10.1016/j.trc.2021.103401
• Languages: English
• ISSNs: 0968-090X

Abstract

Abstract: The paper develops a simulation model and evaluates fixed versus on-demand operational designs of a station-based automated feeder service. The evaluation considers the operational cost and average passenger level-of-service trade-offs as well as distributional differences in waiting times. Two case studies are used to evaluate such trade-offs under different fleet compositions; (1) a simple circular network feeder service; (2) a case based on a real-world coordinated branched service in Stockholm, combining fixed-line services on the trunk portion with a flexible feeder service on the branches. Results for the circular network indicate that there are benefits in utilizing an on-demand operational policy for the lowest and highest demand levels tested. When fixed service capacity is exceeded, it is found that there are potential benefits in on-demand operations with respect to average level-of-service, as well as delivering a more even distribution of passenger waiting times. Results for the real-world case show that combining DRT on branches with fixed services on the trunk improves the overall median waiting times for all DRT scenarios and provides substantial improvements for passengers on the trunk, at the cost of more variable, and less equitable waiting times on the branches. For larger fleet sizes, generalized travel costs are reduced with and without rebalancing and level-of-service provided to branch-to-branch passengers is improved considerably by rebalancing idling vehicles to branch end-stops. The case studies demonstrate the usefulness of the simulation framework in evaluating trade-offs between fixed and on-demand service design variables and their effects on disaggregate level-of-service provided for stop-based feeder services. Highlights: A simulation for station-based DRT integrated with fixed public transit. Evaluation of a circular feeder service and a real-world coordinated branched line. Level-of-service and equity trade-offs are reported for substitute service designs. DRT circular feeder design displays equity improvements in high demand settings. DRT improves level-of-service with lower equity on branches in the real-world case.