FORMATION OF INDEPENDENT FLOW-LINE CELLS BASED ON OPERATION REQUIREMENTS AND MACHINE CAPABILITIES

In this paper we study the generalized grouping problem of cellular ma nufacturing. We propose an operation-sequence-based method for forming flow-line manufacturing cells. Process planning in the form of select ion of the machine for each operation is included in the problem formu lation. Input requirements include the set of operation requirements f or each part type, and operation capabilities for all available machin e types. The objective is to rnd the minimum-cost set of flow-line cel ls that is capable of producing the desired part mix. A similarity coe fficient based on the longest common operation subsequence between par t types is defined and used to group parts into independent, flow-line families. An algorithm is developed for finding a composite operation supersequence for each family. Given machine options for each operati on in this sequence, the optimal machine sequence and capacity for eac h cell is then found by solving a shortest path problem on an augmente d graph. The method is shown to be efficient and computational results are reported.