Mathematical modelling of dynamic facility layout and material handling devices assignment decisions

In order to meet customer expectations in today's changing competitive environment, criteria such as low cost and quick responsiveness have gained importance as well as quality. This leads to need of reducing operating costs. Because during the production, the material handling within the facility is one of the important factors that increase production time and cost. With these material handlings, the assignment of transport devices becomes important. This study aims to minimize inter-department material handling costs and displacement costs of departments. For this purpose, the Dynamic Facility Layout Problem (DFLP), which determines the location of departments within the facility, has been examined. A new mathematical model has been proposed for the DFLP, which is considered together with the parallel flexible bay structure and the assignment of material handling devices. Departments that have unequal areas are assigned to a parallel bay. The proposed approach is modeled by using mixed integer programming method and it has been tested on some problem instances from the literature. The results show that the proposed model solves to for known problem instances effectively. Accordingly, it has been seen that the assignment decisions of material handling devices along with layout decisions enables the different facility layouts.