Research on Dual-Resource Constrained Aircraft Final Assembly Scheduling with Variable Duration

This study investigates a dual-resource constrained aircraft final assembly scheduling problem with variable duration. The dual resources consist of homogeneous and heterogeneous resources. Homogeneous resources refer to a type of resource with a fixed quantity during a period, like space capacity. As for heterogeneous resources in aircraft final assembly, typically multi-skilled assembly workers, may have varying skill mixes and efficiency levels. The heterogeneity of worker resources complicates resource assignments, and simultaneously, introduces variability in assembly outline (AO) duration due to differences in efficiency levels. To address these challenges, a mixed integer linear programming model under complex constraints is established to minimize the assembly cycles. Next, an improved genetic algorithm (IGA) is proposed to find high-quality solutions efficiently. The IGA employs a multi-dimensional chromosome encoding method to determine the priority and heterogeneous resource assignment for each AO, incorporating specialized crossover and mutation operators. Additionally, a serial scheduling generation scheme (SSGS) is utilized to assign homogeneous resources and generate feasible schedules. Finally, the effectiveness of the proposed model and algorithm is demonstrated through a real case study.