A Constrained Programming Model for the Optimization of Industrial-Scale Scheduling Problems in the Shipbuilding Industry

Abstract

This work presents an innovative constrained programming model for solving a flexible job-shop scheduling problem with assemblies and limited buffer capacity based on a real case from the shipbuilding industry. Unlike the existing literature, this problem incorporates the manufacturing and assembly of blocks from subblocks to the final ship erection, while considering the limited buffer capacity due to the size of blocks, which has been often overlooked. The objectives considered are the minimization of the makespan and tardiness based on ship erection due dates. To demonstrate the model’s effectiveness, it is initially validated using various scheduling problems from the literature. Then, the model is applied to progressively challenging instances of the shipbuilding problem presented in this work. Finally, the optimization results are validated and analyzed using a comprehensive simulation model. Overall, this work contributes to reducing the gap between academia and industry by providing evidence of the convenience of the application of constrained programming models combined with simulation models on industrial-size scheduling problems within reasonable computational time. Moreover, the paper emphasizes originality by addressing unexplored aspects of shipbuilding scheduling problems and highlights potential future research, providing a robust foundation for further advancements in the field.