A genetic algorithm for facility layout design in flexible manufacturing systems

The flexible manufacturing system (FMS) facility layout problem (FLP) involves the positioning of cells within a given area so as to minimize the material flow costs between cells. The FLP design includes specifying the spatial coordinates of each cell, the orientation of each cell in either a horizontal or vertical position, and the position of each cell's pickup and dropoff points. The layout design problem is both tactically and strategically important since the layout plays a large role in determining the efficiency and flexibility of the system. The FMS layout problem differs from traditional layout problems in that there are additional constraints on a cell's shape and orientation and the location of the pickup/ dropoff points must be determined. A mixed integer programming formulation for the FLP developed by Das (1993) is adapted and heuristically solved in this paper. Because of the NP-hard nature of the solution space, a genetic algorithm based decomposition strategy is proposed and computationally tested. A comparison of the computational results with the existing methods indicates that the heuristic is a viable alternative for efficiently and effectively generating layout designs for flexible manufacturing systems.