Customised bus service design considering flexible vehicle size and transfer incentivization

In this study, the flexible vehicle size and transfer incentivization strategies are incorporated to increase the potential of the customised bus system. In detail, the modular vehicle system is adopted for flexible vehicle size design since it can be connected as the assembled bus in response to demand variation. Also, the transfer among buses is considered to group passengers with the same destinations to increase bus utilisation. However, the passengers will not actively transfer as it is viewed as a disutility. Thus, the incentivization is provided and the transfer demand is elastic under incentivization. We jointly optimise passenger-route assignment, vehicle size, and incentivization scheme by transforming the original nonlinear programming model into a mixed integer linear programming model. Then, to solve the larger case study, the modified ant colony system algorithm is also proposed. The experiments validate the superiority of customised bus service considering flexible vehicle size and transfer incentivization.