智動化揀貨系統（Robotic Mobile Fulfillment System）是一種在電子商務倉庫中常見之以貨就人的物料搬運系統。機器人扮演著將可移動的貨架抬起到工作站並將之運回儲存區域的角色，雖然使用機器人可透過減少移動和搜索等無效的揀選活動以提高揀選過程之效率，但作為交通工具會消耗過多的能量。因此，使用較少的機器人來完成更多的訂單是優化訂單揀選流程進而減少機器人移動的關鍵點，更可進一步降低機器人的能耗。而較少的機器人意旨在揀貨站中所揀選之貨架數量較少。
本研究著重於考量訂單批次處理概念下之訂單指派原則，同時處理多個訂單以減少揀選貨架之數量並提高堆放值（pile-on）。此外，本研究提出了兩階段之訂單指派方法，此方法可在指派訂單之前識別貨架之狀態，即貨架是否已被指派給訂單與否。
在訂單指派中運用訂單批次處理的概念，相較於一次指派一個訂單，可減少12.64%的貨架使用量，且堆放值從2.87提高至5.28。而本研究所提出之兩階段訂單指派可減少18.97%的貨架使用量，堆放值可高達6.37，且同時產出效率仍是最好的。

Robotic Mobile Fulfillment System (RMFS) is a parts-to-picker material handling system that is well known to be implemented in e-commerce warehouses. Robots play the role of picking up movable shelves, called pods, to the workstations and returning them to the storage area. Although the efficiency of the picking process is improved by reducing ineffective picking activities such as traveling and searching, moving a robot as a means of transportation consumes too much energy. Thus, fulfilling more orders with fewer robots is a crucial point to optimize the order picking process for reducing the robot movement, which can further reduce the energy consumption of robots. Fewer robots means fewer pods are picked at the picking station.
This study focuses on order to pod assignment under consideration of the order batching concept, which deals with a group of orders at the same time, in an attempt to minimize the number of picked pods and provide a high pile-on value. Furthermore, this study proposes a two-phase assignment for order to pod assignment, which can identify the pod status before the assignment.
Rather than handle orders one by one, implementing the order batching concept to the order assignment can reduce the number of picked pods by 12.64%, and increase the pile-on value from 2.87 to 5.28. The proposed two-phase assignment can reduce the number of picked pods by 18.97%, pile-on value can reach 6.37 where the throughput efficiency is still the best.

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