Two-sided assembly line balancing problem with parallel performance capacity

Two-sided assembly line balancing (two-ALB) problems usually occur in plants that produce large high-volume products, such as buses, trucks, locomotives, and home products. In this study, we consider a two-ALB using a new approach that allows the parallel performance of tasks in a real-world locomotive production plant. The problem is formulated as a mixed-integer program and a new heuristic algorithm is proposed, which produces robust results as well as obtaining better quality solutions to some basic two-ALB benchmarks. In fact, the proposed algorithm can obtain optimal solutions for some small-scale problems and near-optimal solutions for some medium-scale problems.