In this paper we propose and study a new paratransit transportation system that integrates accessible taxi (or private hire) services, the most widely used form of disabled transport, with semiflexible public bus services that deviate from their nominal route to provide door-to-door transport. The scope of this system is to serve all paratransit orders received and minimize the overall transport cost under practical service quality imperatives. The proposed system and its design aspects are studied by modeling the related planning problem as a mixed integer-linear program. The program incorporates important cost and service-level considerations, and it is solved to optimality by a new exact branch-and-price approach that leverages two types of subproblems, one per mode. An extensive experimental study has been performed to (a) assess the advantage of integrating the two modes, (b) assess the efficiency of the proposed solution method, and (c) provide system design guidelines for achieving an appropriate balance between system operating costs and service quality.

 

Keywords: Demand Responsive Transit Systems, Paratransit Systems, Door-to-Door Bus Services