Order consolidation in warehouses with compact 3D sorter modules
研究了紧凑型3D分拣模块中订单合并的运营决策问题，提出优化方法可将吞吐效率提升50%以上，对电商和零售仓库管理有参考价值。
In the fast-paced realm of e-commerce and omnichannel retail, the swift consolidation of orders is a crucial bottleneck in today’s distribution centers and warehouses. In this context, compact 3D sorter modules are among the latest inventions. Inside these modules an array of liftable trays circulates along loading stations and shelves to transport picked products from the former to the latter. Each shelf is tasked with gathering products for a particular customer order and is situated on one of the several movable rack carts arrayed around the module’s perimeter. Upon the completion of all orders on a rack, it is detached from the sorter, conveyed to the packing area, and supplanted by a vacant rack. Achieving efficient order consolidation with 3D sorters hinges on resolving several operational decision-making tasks: determining the allocation of orders to shelves, assigning products of identical stock keeping units to specific orders, and tray loading considering delays caused by liftable trays still occupied by a product awaiting dispatch when passing a loading station. This paper models these operational decisions, introduces efficient solution methods, and demonstrates that sophisticated optimization markedly enhances throughput efficiency beyond the capabilities of basic decision-making rules. Our computational results highlight potential performance improvements of 50 % and more.