Minimizing the number of tool switches in flexible manufacturing cells subject to tools reliability using genetic algorithm

Nowadays, flexible manufacturing systems play an effective role in a variety of production and timely response to the needs of their customers. Flexible manufacturing cell is a part of this system that includes machines with flexibility in manufacturing different parts. For many years, minimizing the number of tool switches in the machines has been studied by the researchers. Most research in this field has not considered the limitations related to life and failure of the tool. Therefore, it is necessary to provide a model that, because of restrictions on tool life, the number of tool switches for a flexible cell is minimized. In this study, the impact of the tools reliability on minimizing the number of tool switches is examined. First, a mathematical model is presented for the problem. Because of the complexity of the problem, exact solution of the problem in medium or large sizes is not possible in a reasonable time. Therefore, genetic meta-heuristic algorithm has been used for solving the problem and Keep tools needed soonest (KTNS) policy has been used to determine the optimal arrangement of tools. Then, some examples of such problem have been solved to evaluate the performance of the presented algorithm.