Balancing assembly lines with tabu search

 

Sophie D. Lapierre a,b,_, Angel Ruiz a,c, Patrick Soriano a,d,*

a Centre de recherche sur les transports, Universite´ de Montre´ al, CP 6128, Succursale Centre-ville, Montre´al (Qc), Canada H3C 3J7

b De´partement de mathe´matiques applique´es et ge´nie industriel, E´ cole Polytecnique de Montre´ al, CP 6079,

Succursale Centre-ville, Montre´al (Qc), Canada H3C 3A7

c De´partement ope´rations et syste`mes de de´ cision, Faculte´ des sciences de l’administration, Universite´ Laval,

Que´bec (Qc), Canada G1K 7P4

d Service dc I’enseignement des me´thodes quantitatives de gestion, E´ cole des Hautes E´ tudes Commerciales,

3000 Chemin de la Coˆte-Sainte-Catherine, Montre´al (Qc), Canada H3T 2A7

Available online 12 October 2004

Abstract

Balancing assembly lines is a crucial task for manufacturing companies in order to improve productivity and minimize production costs. Despite some progress in exact methods to solve large scale problems, softwares implementing simple heuristics are still the most commonly used tools in industry. Some metaheuristics have also been proposed and shown to improve on classical heuristics but, to our knowledge, no computational experiments have been performed on real industrial applications to clearly assess their performance as well as their flexibility. Here we present a new tabu search algorithm and discuss its differences with respect to those in the literature. We then evaluate its performance on the Type I assembly line balancing problem. Finally, we test our algorithm on a real industrial data set involving

162 tasks, 264 precedence constraints, and where the assembly is carried out on a sequential line with workstations located on both sides of the conveyor, with two possible conveyor heights and no re-positioning of the product. We discuss the flexibility of the metaheuristic and its ability to solve real industrial cases

_ 2004 Elsevier B.V. All rights reserved.

Keywords: Assembly line balancing; Tabu search; Metaheuristic