Multi-yard-crane routing optimization at container terminals based on a two-stage programming

摘要

The multi-yard-crane routing optimization aims at minimizing the total container handling time by multiple yard cranes which work simultaneously to pick all the designated containers. Being different to the past studies, the problem is formulated as a mixed integer programming that considers inter-crane interference. The number of containers that each yard crane picks at each yard-bay, and the sequence of yard-bays that each yard crane visits, can be decided by solving the model. To solve the model, a two-stage programming method is suggested. In first stage, the branch and bound method is referenced. In second stage, an improved genetic algorithm is designed to solve the optimal routing problem. Finally, the model and algorithm are evaluated by randomly generated scenarios based on practical data. The evaluation proves that the proposed two-stage programming method is feasible and reasonable.