BALANCING ASSEMBLY LINES WITH ACCESSIBILITY WINDOWS. PROBLEM DESCRIPTION AND SOLVING HEURISTIC PROCEDURE

Abstract

ABSTRACT: Assembly line balancing problems (ALBPs) arise when designing or modifying an assembly or production line and usually consist in assigning the tasks to the workstations along the line in order to meet some given objectives. Traditionally, it is assumed that there is exactly one workpiece in each workstation and that the workstation has access to the entire workpiece. In practice, this assumption may be sometimes too restrictive. An example is the case of the automated assembly of printed circuit boards. In this type of lines the length of the workpiece might be larger than the width of the workstation. Therefore, each workstation can only access to the limited portion of the workpieces that fall inside its accessibility window. In this work we present an extension of the ALBP to the case of workstations with accessibility windows (AWALBP). The problem is described and a simple-to-implement solving procedure is proposed, which consists of i) an algorithm to obtain a good initial solution and ii) a simulated annealing algorithm for improving the obtained solution. Finally, a computational experience that validates the proposed procedure is reported. Keywords: assembly line balancing, accessibility windows, heuristics, simulated annealing