A Matheuristic based on Ant Colony System for the Combined Flexible Jobshop Scheduling and Vehicle Routing Problem*

Abstract

Nowadays, market behavior and globalization mean that end consumers are waiting very quickly for their orders to be delivered. This context forces companies to have high availability of finished products. For this reason, the industries that make up the supply chains are obliged to implement strategies to meet this customer need. One efficient practice is the integration of production and transportation activities. In the literature, few research works integrate the scheduling of production tasks with the vehicle routing. This paper aims at proposing a solution approach for the combined problem. The production system configuration is defined as a flexible jobshop, while the distribution problem is modeled as a vehicle routing problem. The proposed approach consists of two parts. First, production makespan is minimized through a hybrid algorithm based on ant colony system and local search. Then, the routing problem is solved optimally using mathematical programming in order to minimize the total travel time. Benchmark instances from the literature are adapted to deal with the combined problem. Experimental results show the efficiency and effectiveness of the proposed algorithm.