An approach to the FMS tool allocation problem with material handling considerations

Abstract

The aim of this thesis is to propose solution methods for solving the tool allocation problem with material handling considerations faced in a Flexible Manufacturing System (FMS). The FMS is assumed be capable of handling alternative process plans, which enables to produce the same part type with different operation sequences. Moreover, the tool slot capacity, machine time limitation, tool copy availability and machine-tool compatibility constraints are considered. The problem is tried to be solved with the objective of minimizing the total distance traveled by the parts during their production. In order to achieve that, the distances between machines, on which the tools are to be mounted, are taken into account. Three mathematical model formulations and a genetic algorithm (GA) is proposed for solving this problem. The proposed mathematical model formulations include a mixed integer non linear programming (MINLP) model and two mixed integer programming (MIP) models. The proposed genetic algorithm on the other hand, utilizes optimal solutions of linear programming (LP) models for determination of the fitness values. The performance of these solution methods are tested by conducting extensive numerical experiments on generated problem instances.