自动化集装箱码头同轨双堆垛起重机交接缓冲贝位优化

Handover buffer bay optimization for same-track double stacking cranes in automated container terminal

在自动化集装箱码头中,堆场作业效率是评估码头整体运作效率的重要指标.为了提高堆场作业效率,采用同轨双堆垛起重机以借助缓冲贝位同时存储和取回集装箱,其中主堆垛起重机将集装箱堆叠在缓冲贝位,协作起重机将其运送到目标贝位.缓冲贝位的设置能规避双堆垛起重机之间的移动冲突,将冲突转移到缓冲贝位上.制定了一个安全时间间隔以避免双堆垛起重机在缓冲贝位上发生碰撞,以最小化任务完成时间为目标,构建了一个混合整数规划模型决策缓冲区位置和作业最优序列.设计算例和数据集,研究安全时间间隔、起重机移动速度、小车处理时间的敏感性,起重机不借助缓冲贝位和借助缓冲贝位完成任务对任务完工时间的影响以及最优缓冲贝位发生变化对任务完工时间的影响.实验证明,安全时间间隔、起重机移动速度、小车处理时间会影响任务完成时间和缓冲贝位;相较于不借助缓冲贝位完成任务的情况,借助最优缓冲贝位完成任务可以减少11.38%的完工时间;而与最差缓冲贝位相比,最优缓冲贝位可以减少49.40%的任务完工时间.

In an automated container terminal,the operation efficiency of the yard is an important indicator to evaluate the overall operational efficiency of the terminal.To improve the operation efficiency of the yard,the same-track double stacking crane is used to store and retrieve containers at the same time with the help of the buffer bay.The main stacking crane stacks the container in the buffer bay,and collaborative crane transports it to the target bay.The setting of the buffer bay can avoid the movement conflict between the double stacking cranes and transfer the conflict to the buffer bay.A safe time interval is used to avoid collisions between the two cranes on the buffer bay,and under the minimization of the task completion time,a mixed-integer program model is constructed to determine the buffer location and sequence of operations.Numerical experiments and data sets are devised to study the sensitivities of the safe time interval,crane moving speed,trolley processing time,the impact of the crane without the help of the buffer bay and with the buffer bay on the task completion time,and the impact of changes in the optimum buffer bay on the task completion time.The experiments show that the safe time interval,crane moving speed and trolley processing time will affect the task completion time and buffer bay.Compared with the situation where the task is completed without the use of the buffer bay,the optimal buffer bay can reduce the task completion time by 11.38%.Compared with the worst buffer bay,the optimal buffer bay can reduce the task completion time by 49.40%.