An Improved Ant Colony Algorithm for Open Vehicle Routing Problem with Time Windows

According to the open vehicle routing problem (OVRP), a vehicle is not required to return to the distribution depot after servicing the last customer on its route. In this paper, the open vehicle routing problem with time windows (OVRPTW) is considered, and a mixed integer programming mathematic model of OVRPTW was proposed in detail. Meantime, an improved ant colony algorithm (IACA) was proposed to overcome the shortcomings of premature convergence and slow convergence of conventional ant colony algorithm (ACA). The experiment results showed that the IACA can solve OVRPTW effectively.