A Variable Neighborhood Tabu Search Algorithm for the Heterogeneous Fleet Vehicle Routing Problem with Time Windows

The heterogeneous fleet vehicle routing problem with time windows is a variant of the classical vehicle routing problem. This paper defines a mathematical model of this problem and proposes a variable neighborhood tabu search algorithm to solve it. The initial solution is obtained by GENIUS and the giant tour algorithm. Our algorithm employs a variable neighborhood mechanism to search the optimal solution based upon four neighborhoods. In addition, the local search results are improved by the tabu search algorithm. The proposed algorithm appears to be effective when tested on benchmark instances from the literature.