Mathematical model proposals for multi-product double row facility layout problem with identical machines

Abstract

Double row facility layout problem (DRFLP) is a frequently used layout type in flexible manufacturing systems. In this layout, machines or departments are placed along both sides of a corridor, which is a path for the use of transportation vehicles and workers. The problem involves determining which side of the corridor the machines will be on and their exact locations on the row in order to minimize transportation costs within the facility. This study focuses on a multi-product DRFLP with different processing routes. New mixed integer mathematical models were developed for the scenarios with and without identical machines. The effectiveness of the models was evaluated on the randomly generated test problems. Optimal solutions were obtained in both models for small-sized problems. For large-sized problems, the solution values reached within pre-determined time limit (21600 s) were reported. While the gap (%) values at the end of the solution time determined in the model without identical machines ranged between 8.05 and 32.26, these values were between 5.26 and 25.73 for the model with identical machines.