Throughput rate optimization in high multiplicity sequencing problems

Abstract

Mixed model assembly systems assemble products (parts) of different types in certain prespecified quantities. A minimal part set is a small-est possible set of product type quantities, to be called the multiplicities, in which the numbers of assembled products of the various types are in the desired ratios. It is common practice to repeatedly assemble minimal part sets, and in such a way that the products of each of the minimal part sets are assembled in the same sequence. Little is known however regarding the resulting throughput rate, in particular in comparison to the throughput rates attainable by other input strategies. This paper inves-tigates throughput and balancing issues in repetitive manufacturing envi-ronments. It considers sequencing problems that occur in this setting and how the repetition strategy influences throughput. We model the prob-lems as a generalization of the traveling salesman problem and derive our results in this general setting. Our analysis uses well known concepts from scheduling theory and combinatorial optimization