Hybrid Heuristics for the Vehicle Routing Problem with Time Windows

This paper addresses the development of effective heuristics for solving the vehicle routing and scheduling problem with time window constraints. Both tour construction and local search tour improvement heuristics are developed. A major premise of the paper is that embedding global tour improvement procedures within the tour construction process can lead to improved solutions. Computational results are reported on test problems from the literature as well as real world applications. The hybrid construction/improvement heuristic is more effective in reducing vehicle fleet size requirements than previously reported heuristics.