Unidirectional loop newtork layout problem in flexible manufactaring systems

Abstract

Unidirectional Loop Networks are the most common architecture in FMSs. This is partly due to lower implementation costs of unidirectional loop networks. But mainly it is the higher flexibility unidirectional loop networks provide that makes then more common. In this thesis we are interested in the arrangement of machines in a unidirectional loop network. Our objective is to determine an assignment of machines yielding the minimum cost defined as the sum of products of the parts moving between machines and the distances moved. We give our formulation of the problem and propose two heuristics; Positional Move Heuristic and Positional Move-Pairwise Interchange Heuristic. The computational effectiveness of these heuristics is compared with other existing heuristics from the literature.