A Model for Heterogeneous Fixed Fleet Vehicle Routing Problem

Transportation is one of the important infrastructures constituting the base and requisite for different levels of people’s access and movement to various locations. Transportation systems are one of the indices of the development of a region. Optimizing these systems contributes to improving performance and reducing costs of offering services to users. Hence, methods should be adopted with which this problem can be efficiently modeled. The final purpose of the vehicle routing problem is fulfilling all needs optimally and with minimum cost. Heterogeneous fixed fleet vehicle routing problem is an applied problem in routing and transportation planning. Its approach is to service customers with a limited number of vehicles through specifying certain routes with minimum cost for transportation fleet that will meet the demands of customers. The composition of vehicle fleet includes several types of vehicles with different capacities. In this research, a practical model and algorithm is proposed and a sample problem is solved by the algorithm and the numerical results are presented. Keywords—vehicle routing problem, heterogeneous fixed fleet, optimization, transportation planning