Solving the Dynamic Routing Problem of the Rehabilitation Bus System in Taiwan

This study presents a system architecture for the rehabilitation bus system in Taiwan. This bus system provides a door-to-door transportation service to the handicapped. The current system is operated on a reservation basis. Instant requests of service are unable to be handled by the operation centre even space is available on the vehicles. Hence, even there is a great demand of the service, vehicle capacity is often idle. The purpose of the proposed system architecture is to improve the utilization of vehicles by accepting instant requests from users. The system contains an information system that can acquire and process both the real-time status of a bus and the relevant information of an instant request, and then response to the user promptly. A dispatching and routing module is incorporated in the system to re-plan the routes of vehicles so the newly arriving request can be satisfied efficiently. In this study, vehicle routing is modeled as a dial-a-ride transportation problem by mathematical programming techniques. Routing solutions are obtained via an algorithm that combines a heuristic method and an optimization solver. Computational results show that the proposed approach can provide satisfactory solutions for dynamic and instant requests of rehabilitation bus service.