An aircraft final assembly line balancing problem considering resource constraints and parallel task scheduling

In this study, the balancing problem of an aircraft final assembly line (AFAL) is investigated. The decision is to assign all the assembly tasks to a given number of workstations, with the objectives to balance the workstation cycle time and to minimize the total resource investment cost. An integer linear programming model is developed to formulate the problem. A construction and improvement based two-stage heuristic approach is proposed to solve this problem. In the first stage, an initial task assignment is constructed based on rules that are evolved by a multi-dimensional archive of phenotypic elites algorithm. In the second stage, an improvement heuristic, consisting of several customized neighborhood operators, is developed to improve the initial task assignment. The proposed approach is compared with the existing methods and its variants. Computational experiments and a real case study reveal the superiority of our proposed approach.