Multi-objective Evaluation Of Dynamic Facility Layout Using Ant Colony Optimization

The Dynamic Facility Layout Problem (DFLP) deals with changes of facility layout throughout time. As an extension to Static Facility Layout Problem (SFLP), it has gathered increasing interests lately. Facility layouts are constantly modified over time either to meet customers' changing demands in product designs and functionalities or to keep pace with technological innovations. Manufacturers must stay flexible and agile and frequent facility layout changes are needed. Since there is often insufficient time and insufficient funding to build a new manufacturing plant, it is often necessary to rearrange the current plant layout. Even though the rearrangement of plant layout can be costly, it is far more cost effective when compared to the possibility of failure to meet customers' demands. Although there is a great volume of research work done in the dynamic facility layout problem (DFLP), often the research in this area focus on few objectives/criteria, i.e. minimizing the product of distance and flow cost, known as the distance-based objective. Focusing on the distance based Objective Function Value or OFV is not adequate to reflect situations in the real world-- little consideration is given to the "quality" aspect of facility layout such as the adjacency of facilities (e.g., noise, RF signal, dusts or safety reasons) that require placing them as far as possible. The adjacency-based objective should also be considered in facility planning. The purpose of the research is to develop a technique to solve the dynamic facility layout problem with multiple objective approach, both qualitative and quantitative, using one of the popular meta-heuristics-- the Ant Colony Optimization (ACO). The results indicate this heuristic technique provides a practical decision support tool to solve the issues in the dynamic facility layout problem.