Solution to large facility layout problems using group technology
In this work, a systematic methodology to construct cellular layouts using GT technique for large size problems has been developed. Previous researches in this field have addressed heuristics that can be used to solve only medium size problems. A mathematical model that uses reduced intercellular count as a criterion for cell formation is developed. The developed model includes details like machine sequence, production volume and machine revisits for formation of cells. A performance measure that is used to evaluate the cells being formed is proposed after some modifications in the existing method from Nair & Narendran (1998). Once the cell configurations are evaluated, separate layouts are developed for each cell depending on the amount of flow between machines within their respective cell. The best configuration is selected based on the least material handling cost that a configuration accounts for. This process defines entire steps of the proposed approach. The validity of the proposed approach was verified using small, medium and large case studies. From the case study results, it is concluded that the proposed methodology can be used to solve large facility layout problems using GT. The developed model proved to be efficient irrespective of the size of the problem considered, even after inclusion of details such as machine sequence, production volume and machine revisits along with the performance measure for the cells formed. By restricting the number of cell configurations between an upper and lower limit, the model eliminated the possibility of unwanted configurations that increases the complexity of the problem. So for a large size facility layout problem, the proposed method can be used to get the actual number of intercellular movement between cells and also can be used to select the best configuration for a given production plan using reduced material handling cost as the criteria.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering