Planning and Design of Flex-Route Transit Services

Abstract

A theoretical investigation is presented of various issues involved in the planning and design of flex-route transit services. An analytical model is proposed for an idealized operating environment with the objective of determining the optimal slack time that should be allocated to a flexroute segment. The optimization objective is defined to minimize total operator and user cost, which enables a systematic examination of complex interactions among the system parameters. An equation is derived for the relationship between the number of feasible deviations and various system parameters such as slack time, zone size, and dwell time. Subsequent analysis shows that the analytical model is elaborate enough to provide substantial insights into various issues that may arise in designing a flex-route service. A simulation analysis is conducted to validate some of the conclusions drawn from the analytical model and to further analyze the implications of stochastic variation in passenger demand.

Get full access to this article

View all access options for this article.

References

Rosenbloom

Service Routes, Route Deviation, and General Public Paratransit in Urban, Suburban, and Rural Transit Systems. AZ-26-7000. U.S. Department of Transportation, FTA, Washington, D.C., 1996.

Farwell

R. G.

, and Marx

. Planning, Implementation, and Evaluation of OmniRide Demand-Driven Transit Operations: Feeder and Flex-Route Services. In Transportation Research Record 1557, TRB, National Research Council, Washington, DC, 1996, pp. 1–9.

Durvasula

K. P.

, Smith

B. L.

, Brich

S. C.

, and Demetsky

M. J.

. An Investigation of Route Deviation Transit Service Design. Presented at the 78th Annual Meeting of the Transportation Research Board, Washington, D.C, 1999.

Welch

, Chisholm

, Schumacher

, and Mundle

S. R.

. Methodology for Evaluating Out-of-Direction Bus Route Segments. Transportation Research Record 1308, TRB, National Research Council, Washington, D.C., 1991, pp. 43–50.

Simulation Model for Evaluating Intelligent Paratransit Systems. In Transportation Research Record: Journal of the Transportation Research Board, No. 1760, TRB, National Research Council, Washington, D.C, 2001, pp. 93–99.