Packing items to feed assembly lines

We treat a practical application of packing problems in feeding assembly lines. This study was motivated by a real situation encountered in the shop floor of a major automobile industry plant in Brazil. The assembly line feed problem (LFP) consists in how pack the items in the available containers to meet the line work centers' requirements with a minimum total cost over the planning horizon. UP is a variable-sized bin packing problem that has two special features: (i) a cardinality constraint on each bin's size; and, (ii) a cost structure such that each bin's cost varies according to the items that are packed in it. We propose an integer programming model and a GRASP heuristic for LFP. Numerical results on real-life test instances are reported. (C) 2006 Elsevier B.V. All rights reserved.