A comparison of constrained and ad-hoc demand-responsive transportation systems

Ronald, N., Thompson, R.G., and Winter, S. A comparison of constrained and ad-hoc demand-responsive transportation systems, Proceedings of the 94th Annual Meeting of the Transportation Research Board, Washington, DC, January 2015.

Planning public transport services for areas of low population density is important to enable those without convenient travel options to travel. In these areas, transit vehicles frequently travel with low numbers or even no passengers on board, therefore incurring more cost to the transport providers. Demand-responsive transportation (DRT) services are a potential efficient mobility solution to this problem.

The choice of DRT scheme is important as different types of schemes might produce different performances in the same area with the same demand. While many DRT schemes have some constraints, for example, a fixed route or a fixed time, these impose constraints on users who are already constrained, for example, due to lack of access to a car or limited times to undertake activities. Removing the fixed constraint on time leads to evaluating the performance of an ad-hoc system.

matsim-ymThe aim of this paper is to investigate the change in performance between two different DRT schemes — a fixed-time but flexible route scheme and a completely ad-hoc scheme — using MATSim, a large-scale agent-based transport simulation, and real data from an existing fixed-time DRT service in rural Victoria, Australia. Experimentation showed that the schemes produced different outcomes for the operator and passengers, however the optimization algorithm is less important in areas of low demand. Higher levels of demand lead to extensive vehicle travel for an ad-hoc service, while altering the headways between fixed-time services could achieve a middle ground for operators and passengers.

This work is the first step towards developing a decision-support tool to evaluate different DRT schemes, in particular integrated with other modes of transport.

Please email the authors for a copy.