Balancing of manufacturing systems with complex configurations for delayed product differentiation

In response to increasing product variety, manufacturing systems with complex asymmetric configurations have often been used for delayed product differentiation. Balancing these types of manufacturing systems, however, is a challenge, since existing line balancing methods usually have been developed for symmetric configurations, such as serial lines with parallel machines at some stages. This paper proposes a novel binary integer programming (BIP) model for task-machine assignment and workload balancing in complex asymmetric configurations for mixed-model production. The new model includes (1) mathematical representations of task relations and system configurations, (2) constraint equations for task precedence relations in asymmetric configurations, and (3) constraint equations for parallel/serial relations among tasks. This study extends the area of line balancing and task-machine assignment problems to asymmetric system configurations, and helps to select a configuration from alternatives.