Flow shop scheduling to minimize the total completion time with a permanently present operator: Models and ant colony optimization metaheuristic

This paper studies the one-operator m-machine flow shop scheduling problem with the objective of minimizing the total completion time. In this problem, the processing of jobs and setup of machines require the continuous presence of a single operator. We compare three different mathematical formulations and propose an ant colony optimization based metaheuristic to solve this flow shop scheduling problem. A series of experiments are carried out to compare the properties of three formulations and to investigate the performance of the proposed ant colony optimization metaheuristic. The computational results show that (1) an assignment-based formulation performs best, and (2) the ant colony optimization based metaheuristic is a computationally efficient algorithm.