李明1,2,吴耀华2,张健2,陈宁宁3
(1. 山东建筑大学信息与电气工程学院,山东 济南250101;2. 山东大学控制科学与工程学院,山东 济南 250061;3. 济南大学经济学院, 山东 济南250022)
摘要:为提高阵列式自动拣选机的拣选效率,提出了基于品项相关性的货位优化方法。针对阵列式自动化拣选机通道列串行拣选、并行合流的工作特点,分析设备通道列作业时序,建立阵列式自动拣选机订单拣选总时间数学模型,将其归结为以最大总虚拟视窗时差为目标的货位分配问题。为求解该问题,设计启发式聚类算法,将相关性强的品项分配至间隔距离远的通道存储,以增大总虚拟视窗时差,提高设备拣选效率。某医药物流配送中心阵列式自动拣选机的实例分析表明,采用启发式算法可使订单拣选总时间减少约5%。
关键词:自动化拣选;数学模型;货位分配;品项相关性;启发式算法
中图分类号:TP278 文献标识码:A
Slotting Optimization in an Array Automated Picking DeviceBased on Item Correlations
LI Ming1,2,Wu Yao-hua2,ZHANG Jian2 ,CHEN Ning-ning3
(1. Information and Electric Engineering College, Shandong Jianzhu University, Jinan 250101, China;2.School of Control Science and Engineering, Shandong University, Jinan 250061, China;3. School of Economics, University of Jinan, Jinan 250022, China)
Abstract:To improve the picking efficiency of an array automated picking device, a slotting method based on the item correlations was proposed. By analyzing the operation timing sequence of channel columns based on serial picking and parallel merging method in the array automated picking device, a math model for the total order picking time was established. This problem was converted into the slotting optimization model with the objective maximizing the summation of time difference of the virtual window zone. A heuristicclustering algorithmwas proposed to solve this problem. Through the algorithm, items with closer relationship were assigned into channel columns far apart from each other in order to increase the summation of time difference of the virtual window zone, and improve the picking efficiency. Finally, simulation experiments of array automated picking devices in the pharmaceuticals distributions centre showed that the algorithm could reduce the total order picking time by 5%.
Key words:automated picking; mathematical model; storage location assignment; item correlations; heuristic algorithm
0 引言
订单拣选作为仓库集成系统的一个重要环节,是影响配送中心运行效率的关键因素。现有订单拣选系统分为人到货、货到人和自动化拣选三种类型[1]。在人到货拣选系统中,拣选人员到分拣区内指定储位进行拣选,为保证拣选的准确性与高效率,通常借助电子标签提示、RF手持无线终端或语音提示等设备,提高寻找货物的准确率和效率;在货到人拣选系统中,借助自动化旋转货架、堆垛机式自动存取立体库、自动导引车等设备将货物以箱为单位从仓库中取出,拣选人员根据电子标签提示完成订单拣选,可有效减少人工找货的行走时间;自动化拣选系统采用A字机为代表的通道式自动拣选设备完全代替人工拣选,高效准确地完成订单拣选作业。
随着电子商务和连锁零售的高速发展,多品种、小批量和高时效性的订单日益增多,自动化拣选系统因订单履行效率快、准确性高、人工成本低,在物流配送中心得到广泛应用。A字机为代表的通道式自动拣选设备拣选通道沿输送带平行排列,单一货物品项分拣占地面积大,面对海量品项拣选时常因空间布局限制而无法使用,为此阵列式自动拣选机设计研发并得到成功应用[2]。如图1所示,该设备采用密集流利式货架作为设备主体、电磁铁或步进电机作为货物弹出机构,在输送带上方多个货物拣选通道平行叠放构成通道列,设备由多个通道列组成,通道拣选出的药品通过倾斜挡板下滑到输送带上,相同长度输送带对应的选通道数量约是A字机的10倍,货物弹出速度是A字机的1/3。在配送中心现场,阵列式自动拣选机通常与A字机组合使用,A字机适合处理周转率高但品项数量少的货物,阵列式自动拣选机适合处理周转率较小但品项数量多的货物[2]。