CN104903922B - Fill order at inventory stand - Google Patents

Abstract

A system includes an inventory holder and a mobile drive unit. The inventory holder includes a first side and a second side, the first side including a defined area where inventory holders are designated for placement. The inventory holder is operable to receive inventory items from at least one of the inventory holders at at least one of the defined areas. The mobile drive unit is operable to transport an order holder along the second side of the inventory holder, wherein the order holder is operable to receive inventory items from the inventory holder at a location along the second side of the inventory holder.

Description

Fill order at stock stand

Background of the invention

Modern inventory systems face increased demands to fulfill orders efficiently, despite the increased complexity and variety of inventory and orders. Inventory systems that suffer from inefficient use of system resources face low system throughput, incomplete or delayed tasks, and unacceptable response times. Thus, such inventory systems are challenged to more efficiently use time, space, equipment and manpower to meet their elevated demands.

Brief description of the drawings

For a more complete understanding of the present invention and its advantages, reference should now be made to the following description taken in conjunction with the accompanying drawings, in which:

1 is a perspective view illustrating components of an inventory system including an inventory holder according to an example embodiment;

2 illustrates a side view of various components of an inventory system capable of filling orders using inventory holders;

3 illustrates a top view of another example embodiment of an inventory system capable of filling orders using multiple inventory holders;

4 illustrates a top view of another example embodiment of an inventory system capable of filling orders using multiple inventory holders;

Figure 5 illustrates certain techniques for fulfilling orders using inventory holders;

6 is a flowchart of an example method of filling an order using an inventory holder;

7 is a flowchart illustrating an example method of facilitating fulfillment of an order at an inventory holder;

8 is a flow diagram illustrating an example of facilitating fulfillment at an inventory holder; and

9 illustrates an example computing system that may be used for one or more portions of the systems and methods disclosed herein.

Detailed ways

Many entities utilize inventory systems to store and manage inventory. For example, some retailers may utilize warehouse shelving that stores inventory items in individual bins. When a retailer needs to fill an order for a particular inventory item, workers typically retrieve the inventory item from the bin where the inventory item is stored.

The inventory system of the present disclosure may utilize one or more mobile drive units to automatically retrieve inventory holders from warehouse storage. Inventory holders may be complete racks, where each rack has bins for individual inventory items. A mobile drive unit may be a robotic device configured to independently move around a warehouse. Racks may be transported by mobile drive units to stations for performing inventory operations. Stations may include operators and/or automated equipment to remove required inventory items from inventory holders and fulfill orders. The ability of mobile drive units to deliver inventory items to stations to perform inventory operations, rather than or otherwise manually retrieving inventory items from fixed racks by workers, can greatly increase the efficiency and productivity of the inventory system. For example, by utilizing mobile drive units, an inventory system may be able to fulfill more orders per hour than previous solutions. Mobile units may move around the warehouse and/or retrieve inventory holders in response to commands and/or instructions received from the automated guidance system. For example, a management module may control the supervision and coordination of specific elements and/or tasks within a warehouse. The management module may receive orders for inventory items in the warehouse and coordinate task assignments to fulfill the orders, including providing instructions to mobile drive units to deliver racks with requested inventory items to inventory stations to fulfill the orders. The management module can also provide instructions on how to assemble the order at the inventory station.

To use a simple illustration, in the distribution warehouse of an office supply store, the management module may receive an order for a printer, several ink cartridges, and paper boxes. The management module can determine the location of the items within the storage racks in the distribution warehouse. The items may for example be on a shelf of three separate shelves. The management module can issue tasks to have three different mobile drive units retrieve each rack that holds printers, ink cartridges, and paper, respectively, and have the mobile drive units ship hold these items to where orders for three of the items can be packed into boxes for shipping Shelving for stocking stations. In doing so, the management module can coordinate the various tasks so that all orders received by the management module are fulfilled in an efficient manner.

In many inventory systems, a small percentage of high velocity and/or high volume inventory is responsible for a large percentage of overall system activity. High-velocity inventory may refer to inventory requested by a large percentage of orders, while high-volume inventory may refer to high-volume inventory requested by orders. Volume may refer to the physical quantity of cubic space that a particular inventory item requires in a warehouse. High-volume inventory items can refer to large or bulky items and/or items purchased in bulk on individual orders. In a particular inventory system, up to 1% of inventory items can account for more than 20% of the total system activity. Highly popular items may require corresponding height usage of the mobile drive unit to transport the stock holder to the stock station. Similarly, high-volume inventory may require relatively more labor to replenish the stock holders that store such items, so that dismantling such items into stock holders may be more efficient than ordering them only as they arrive from the wholesaler. Inventory is more efficient. A more efficient method of filling orders for such items can be achieved using inventory holders. Inventory holders store popular and/or high-volume inventory. Stock holders for storing popular or high volume stock can be positioned along the side of the stock holder. The inventory holder can thus be configured to include a configurable number of fixed positions for a maximum number of inventory items. For an example inventory system storing 3,000 unique inventory items, as few as thirty unique inventory items may account for a high percentage of system activity due to the high velocity or high volume of such items. Thus, in such an inventory system, the inventory holder may include a sufficient amount of defined area to store a maximum of 30 inventory items at the inventory holder. The order holder may, for example, be a shelf configured to hold boxes or containers to be used to fill orders for inventory items. Each box or container can be associated with a specific order. For example, an order holder may store cartons for shipment of an order of several ink cartridges and several reams of paper. An order holder with an order requiring such an item may access a location along the inventory rack corresponding to the inventory holder storing the inventory item required for the order. The operator can remove items from the inventory holder and place them into appropriate boxes or containers in the order holder. The order holder can then be taken to an inventory station to fill the order holder's box or container with the items left on the order, if desired.

To illustrate, in the office supply example discussed above, paper may be a high volume inventory item and ink cartridges may be a popular item. Thus, cardboard and stock holders storing various ink cartridges can be placed at the stock holders. An order for several packages of paper and ink cartridges can be filled by moving the order holder along the inventory rack opposite the pallet where the paper is stored to a position where an operator can deliver the paper to the order holder. The order holder can then be moved to a position relative to the stock holder that stores the ink cartridges and where the same or a different operator can deliver the ink cartridges to the order holder. If the requested printer is not stored at the inventory holder, the mobile drive unit may transport the order holder to the inventory station, where another mobile drive unit may transport the inventory holder containing the printer so that the order can be filled.

Technical advantages of certain embodiments of the present disclosure include the ability to provide systems and methods for fulfilling orders using inventory holders. Technical advantages may include the ability to place high volume and/or high velocity objects at inventory holders. As demand for inventory items changes within the inventory system, the management module may include the ability to replace inventory at the inventory rack, thus ensuring that the highest velocity and/or volume items are readily available at the inventory rack. Another technical advantage may include the ability to group individual orders into order holders based on the items in the order located at the inventory holder. Thus, several orders shipped by a single mobile drive unit can be fulfilled by a single order holder at substantially the same time. Additionally, multiple order holders may move along the inventory rack simultaneously and/or in parallel, allowing orders in multiple order holders to be filled substantially simultaneously. Accordingly, the inventory system may be able to achieve greater operational efficiencies than would otherwise be achieved using conventional techniques. Inventory systems that use inventory racks to fulfill orders may be able to invest less mobile drive units in fulfilling orders than using only inventory stations and/or traditional picking methods. Furthermore, the drive time of the mobile drive unit that would otherwise be required to transport multiple stock holders to fill an order for high velocity items can be reduced and/or devoted to other tasks within the inventory system. A further technical advantage of certain embodiments of the present invention may include providing a flexible and scalable inventory storage solution that can be easily adapted to accommodate system growth and modifications. A further technical advantage of certain embodiments of the present invention may include providing a flexible and scalable inventory storage solution that can easily accommodate system growth and changes. Other technical advantages of the present invention will be apparent to those skilled in the art from the following figures, descriptions and appended claims.

While specific examples having specific advantages have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages. Embodiments of the present invention and advantages thereof are best understood by referring to FIGS. 1-9 , wherein like numerals refer to like and corresponding parts of the various drawings.

FIG. 1 is a perspective view illustrating components of an inventory system 10 including an inventory holder 50 according to an example embodiment. As shown, inventory system 10 also includes management module 15 , various mobile drive units 20 , inventory holder 30 , pallet holder 34 , waste holder 36 , and order holder 40 . As shown, inventory holders 30 , pallet holders 34 , and trash holders 36 are positioned along one side of inventory holder 50 at a defined area 80 . Inventory holders 30 and pallet holders 34 may generally hold inventory items 42 and remain stationary at defined area 80 while one or more operators at inventory holder 50 fill orders. However, mobile drive unit 20 may transport inventory holders 30 and pallet holders 34 to and from defined area 80 at various times. For example, as shown, one mobile drive unit 20 may remove the pallet holder 34 from the inventory holder 50 while the other mobile drive unit 20 replaces the pallet with a new pallet holder 34 holding a pallet of additional inventory items 42 Holder 34. To fill the order, mobile drive unit 20 moves order holder 40 to a position along the opposite side of inventory holder 50 . At various locations, mobile drive unit 20 may be slowed and/or stopped so that operators and/or automated equipment at inventory holders 50 may remove requested inventory items 42 from inventory holders 30 and/or pallet holders 34 And place it into the container 60 in the order holder 40 . In some embodiments, the operator of inventory holder 50 may be automated equipment and/or human personnel. As shown, order holder 40 may start at one end of inventory holder 50 and move along a side end until reaching the opposite end. In some embodiments, order holder 40 is movable directly along inventory holder 50 to a position at which inventory item 42 can be received. The order holder 40 can then move along the side of the inventory holder 50 after receiving the inventory item 42 (as indicated, for example, by the dashed arrow in FIG. 1 ) to where it can receive another inventory item 42 from the inventory holder 50 and/or A location from which another inventory item 42 may be removed. After accessing inventory holder 50 , order holder 40 may be shipped to other appropriate locations in inventory system 10 . For example, if the order in the order holder 40 is complete, the order holder 40 may be shipped to a shipping station.

Management module 15 receives and/or generates requests and may initiate other activities related to mobile drive units 20, inventory holders 30, pallet holders 34, order holders 40, inventory items 42, inventory holders 50, and/or inventory system 10. Element-specific operations. Management module 15 may select components of inventory system 10 to perform various operations and communicate commands, instructions, and/or other appropriate information to the selected components to facilitate completion of those operations. Management module 15 may receive orders for various inventory items 42 and may coordinate and manage various appropriate tasks to fill the orders. Management module 15 may receive orders from any suitable system or component, and may alternatively or additionally generate and assign tasks to various components of inventory system 10 . In particular embodiments, management module 15 is based in part on order generation task assignments that include requests for inventory items 42 that management module 15 receives from other components of inventory system 10 and/or from external components in communication with management module 15 . Based on the order, management module 15 may identify specific operations to be completed involving inventory items stored or to be stored within inventory system 10 and may represent any suitable form of communication. For example, in certain embodiments, an order may specify that a customer has purchased a particular inventory item 42 that will be retrieved from inventory system 10 for customer shipment.

After generating one or more task assignments, management module 15 selects the appropriate components to complete a particular task and communicates the task assignments to the selected components to trigger completion of the associated task. The relevant components then perform their assigned tasks. Each task assignment defines one or more tasks to be accomplished by a particular component. These tasks may involve retrieval, storage, replenishment, and counting of inventory items and/or management of mobile drive units 20, inventory holders 30, pallet holders 34, order holders 40, inventory holders 50, and other components of inventory system 10 . Depending on the component and the task to be accomplished, a particular task assignment may identify a location, component, and/or action associated with the corresponding task and/or any other appropriate information to be used by the component associated with the assigned task.

While the appropriate components of inventory system 10 complete assigned tasks, management module 15 may interact with relevant components to ensure efficient use of the space, equipment, labor, and other resources available to inventory system 10 . For example, management component 15 may receive information from various components of system 10 regarding its current location, status, and/or other characteristics. Based on knowledge of the location, current status, and/or other characteristics of the various components of inventory system 10 and knowledge of currently completed tasks, management module 15 can generate tasks, allocate usage of system resources, and otherwise guide in a manner that optimizes operations from a system-level perspective Tasks performed by individual components. Furthermore, particular implementations of inventory system 10 may be capable of supporting a multitude of techniques for efficiently performing various aspects of inventory system 10 operations by relying on both centralized, system-level management and localized, specific decision-making components.

As a result, some embodiments of management module 15 may enhance the efficiency of inventory system 10 and/or provide other operational advantages by implementing one or more of the management techniques described below. For example, management module 15 may determine specific inventory holders 30 and/or pallet holders 34 to be placed at inventory holders 50 based on determining when to place them, which may reduce overall system activity. Similarly, management module 15 may group orders into order holders 40 and assign tasks to fulfill the orders at inventory holders 50 so that order fulfillment activities are optimized. A more detailed description of example operations of management module 15 is discussed below with reference to FIGS. 3-8 .

Mobile drive unit 20 transports inventory holders 30 , pallet holders 34 , and/or order holders 40 between different locations within a work cell associated with inventory system 10 . Mobile drive unit 20 may represent any device or component suitable for use in inventory system 10 based on the characteristics and configuration of inventory holder 30 , pallet holder 34 , order holder 40 , and/or other elements of inventory system 10 . In a particular embodiment of inventory system 10, mobile drive unit 20 represents an independent self-powered robotic device configured to move freely about an associated work cell. In an alternative embodiment, mobile drive unit 20 represents an element of tracked inventory system 10 configured to move inventory holder 30 along a track, rail, cable, or other guiding element traversing an associated bay. In such an embodiment, mobile drive unit 20 may receive electrical power through a connection to a guiding element, such as an electrical rail. In some embodiments, inventory system 10 may include two or more different types of mobile drive units 20 of various suitable capabilities and sizes. Furthermore, while mobile drive unit 20 is shown and discussed as being a particular type of mobile drive unit, mobile drive unit 20 may refer to various types of mobile drive units as appropriate. For example, one type of mobile drive unit 20 is operable to transport pallet holders 34 and/or relatively large, heavy, or bulk inventory items 42 . Another type of mobile drive unit 20 is operable to transport inventory holders 30 , order holders 40 , and/or relatively lighter and/or more compact inventory items 42 . Mobile drive units 20 may thus have various drive trains, load capacities, and other suitable specifications to transport particular inventory items 42 in various inventory holders within inventory system 10 .

Mobile drive unit 20 may be capable of communicating with management module 15 to receive information identifying selected inventory holders 30 during operation, communicate the location of mobile drive unit 20 , or exchange any information used by management module 15 or mobile drive unit 20 . other appropriate information. Mobile drive unit 20 may communicate wirelessly with management module 15 using a wired connection between mobile drive unit 20 and management module 15 and/or in any other suitable manner. As an example, some embodiments of mobile drive unit 20 may communicate with management module 15 using Wi-Fi (IEEE 802.11), Bluetooth (IEEE 802.15), Infrared Data Association standards, or any other suitable wireless communication protocol and/or communicate with each other. As another example, in a tracked inventory system 10, rails or other guiding elements on which mobile drive unit 20 moves may be wired to facilitate communication between mobile drive unit 20 and other components of inventory system 10 .

The inventory holder 30 stores inventory items 42 . In some embodiments, inventory holder 30 includes multiple storage bins, where each storage bin is capable of holding a different type of inventory item 42 . Inventory holder 30 can be carried, rolled or otherwise moved by mobile drive unit 20 . Each inventory holder 30 may have multiple surfaces, and each bin may be accessed by a specific surface of the associated inventory holder 30 . Mobile drive unit 20 may be configured to rotate inventory holder 30 at appropriate times to present a particular surface of inventory holder 30 and associated bins to an operator or other component of inventory system 10 . FIG. 2 illustrates an example embodiment of inventory holder 30 in more detail.

The pallet holder 34 represents one type of inventory holder 30 operable to store pallets of inventory items 42 . In some embodiments, the pallet holder 34 can be carried, rolled, or otherwise moved by the mobile drive unit 20 . The pallet holders 34 may store bulk containers and/or high volume inventory items 42 . Thus, in certain embodiments, a pallet holder 34 may include a large number of inventory items 42 with a single SKU. In some embodiments, the pallet holder 34 represents a container that holds a particular inventory item 42 upon receipt from a wholesaler or distributor of the inventory item 42 . Accordingly, in some modes of operation, pallet holders 34 may be moved directly from entry points into inventory system 10 to inventory holders 50 in response to the volume and/or velocity of inventory items 42 on a particular pallet holder 34 .

Trash holder 36 stores trash and/or waste materials. Waste holder 36 may represent a bin, rack, container, or other structure configured to store common types of waste material generated by inventory holder 50 that may be generated at inventory holder 50 as a result of its operation. For example, shrink wrap and/or other waste may be removed from the pallets on the pallet holders 34 as the pallets are disassembled. As another example, individual inventory items 42 may be removed from packages or other disposable containers as the inventory items 42 are used to fill an order. When the package or other disposable container is empty, it can be placed into the waste holder 36 for disposal. In some embodiments, waste holder 36 may be configured such that it is transportable by mobile drive unit 20 . As described in more detail below with reference to FIG. 2 , the waste holder 36 may interface with the mobile drive unit in a similar manner as the inventory holder 30 . From time to time, the management module 15 may instruct one of the mobile drive units 20 to move the waste holder 36 away from the inventory holder 50 to be emptied.

The order holder 40 holds a set of containers 60 in which inventory items 42 can be packaged into orders. Container 60 may be configured to store orders for various inventory items 42 . Order holder 40 may have any suitable structure and be configured to store containers 60 in any suitable manner based on the type of containers 60 utilized in inventory system 10 or any other suitable factor. In some embodiments, order holder 40 represents a type of inventory holder 30 configured to carry pallets and movable by mobile drive unit 20 . Order holder 40 may include one or more platforms or shelves on which containers 60 rest. Additionally or alternatively, order holder 40 may include multiple bins, each holding a different size or type of container 60 . Order holder 40 and/or container 60 may be designated for shipment to a remote location, such as a shipping destination. Container 60 represents any suitable form of container in or on which inventory item 42 may be placed for storage, shipping, or other suitable purpose. Examples of containers 60 include, but are not limited to, boxes, pallets, bins, cartons, and envelopes. In particular embodiments, the containers 60 are separate from the order holder 40 that stores the containers 60 , and thus, the containers 60 may be removed from the order holder 40 for processing or transferred to other order holders 40 . As an example, container 60 may represent a case or pallet in which inventory items 42 associated with a particular order may be stored for delivery and the associated container 60 may then be shipped to the customer associated with said order. As another example, container 60 may represent a bin or other container in which inventory items 42 may be placed for long-term storage and then moved to a shipping location or removed from inventory system 10 . FIG. 2 illustrates an example embodiment of order holder 40 and container 60 in more detail. More detailed examples of mobile drive unit 20 , inventory holder 30 , and order holder 40 are discussed in greater detail below with reference to FIG. 2 .

Inventory item 42 represents any object suitable for storage, retrieval, and/or processing within automated inventory system 10 . For purposes of this description, an "inventory item" may refer to any one or more objects of a particular type stored in inventory system 10 . For example, a given inventory item 42 may represent a single stock keeping unit (SKU) of a unique inventory item. Accordingly, an inventory item 42 may refer to a specific item and/or may refer to a quantity of an item suitably having a specific SKU. As one example, inventory system 10 may represent a retail distribution warehouse that stores bulk inventory items 42 for a retail facility, such as a grocery store and/or a merchandise warehouse. As another example, inventory system 10 may represent a mail-order warehouse facility, and inventory items 42 may represent merchandise stored in the warehouse facility. During operation, mobile drive unit 20 may retrieve inventory holder 30 containing one or more inventory items 42 requested in an order to be packaged for delivery to a customer. Furthermore, in certain embodiments of inventory system 10, the boxes containing completed orders may themselves represent inventory items.

Inventory station 50 represents any suitable component for processing or manipulating inventory items 42, such as scanners for monitoring the inflow and outflow of inventory items 42 in inventory system 10, communication interfaces for communicating with management module 15, and/or any other appropriate components. Inventory holder 50 includes a number of defined areas 80 where inventory holders 30 and/or pallet holders 34 may be seated. The inventory holder 50 is arranged such that the order holder 40 is operable to move along opposite sides from the defined area 80 of the inventory holder 30 and/or the pallet holder 34 . Order holders 40 moving along inventory racks 50 may receive inventory items 42 from human operators and/or automated equipment. Operators and/or automated equipment at inventory holder 50 are operable to remove inventory items 42 from inventory holders 30 and/or pallet holders 34 and move them into appropriate containers 60 in order holders 40 . The inventory holder 50 may thus include appropriate display and/or signaling devices to instruct the operator which inventory item 42 is to be placed into which container 60 . Additionally or alternatively, the inventory holder 50 may include one or more indicators that, upon activation, provide the operator with where to expect a particular order holder 40 to stop and/or slow down along the inventory holder 50 to receive a particular inventory item 42 instructions. The indicator may be any suitable audio and/or visual signaling device, such as a display interface, light, laser, or other suitable device capable of providing information to the operator of inventory holder 50 .

Inventory holder 50 may be fully or partially controlled by an operator, or may be fully automated. Additionally, human operators or automated operators of inventory holders 50 may be able to perform certain tasks on inventory items 42 , such as packing or counting inventory items 42 as part of the operation of inventory system 10 . Inventory holder 50 may be divided into an appropriate number of work areas for each operator. Manipulators can work in each work area. Workspaces may be used by management module 15 to balance and/or coordinate assignments at inventory holders 50 . For example, inventory holders 30 and/or pallet holders 34 may be assigned to work zones based on the relative speed at which inventory items 42 are balanced among the various zones. As another example, inventory holders 30 and/or pallet holders 34 may be assigned to work zones based on a random velocity at which inventory items 42 are balanced among the various zones. Inventory holder 50 may include one or more raised and/or flat surfaces configured to facilitate operator interaction with inventory holder 30 , pallet holder 34 , waste holder 36 , and/or order holder 40 . Additionally or alternatively, inventory holder 50 may represent an area of a workshop designated for one or more of the activities described herein. Accordingly, inventory holder 50 may represent a virtual area of inventory system 10 at which the activities described in this disclosure take place. The virtual area defining inventory holder 50 can virtually bound two or more sides designated for the activities described herein, including positioning inventory holders 30 and/or pallet holders 34 on one side and/or placing orders The holder 40 is moved into position along the opposite side. Management module 15 may define and/or be programmed to interact with a virtual area of a bay designated as inventory holder 50 .

Defined area 80 may represent a space adjacent inventory holder 50 where inventory holder 30 , pallet holder 34 , and/or waste holder 36 may be positioned when order is filled at inventory holder 50 . The defined area 80 may have an area corresponding to the dimensions of the inventory holder 30 , the pallet holder 34 and/or the waste holder 36 . Defined area 80 may represent a fixed location positioned along a side of inventory holder 50 . The defined area 80 may represent a virtual space defined by the management module 15 . It should be noted that while illustrated as contiguous spaces that are generally similar in size to one another, defined area 80 may be of different dimensions and/or may be positioned in any suitable position relative to inventory holder 50 . For example, defined area 80 may have different dimensions depending on the respective dimensions of inventory holder 30 , pallet holder 34 , and/or waste holder 36 . Thus, in some embodiments, defined area 80 may be of different types designated for a particular type of retainer. In other embodiments, defined area 80 may be sized such that it is generally interchangeable between different types of holders located at inventory holder 50 . In some embodiments, the defined area 80 may simply represent the area along the sides of the inventory holder 50 reserved for placement of the holders 30 , pallet holders 34 , and/or waste holders 36 .

In general, inventory holders 50 are used to fill orders for inventory items 42 . Inventory items 42 , inventory holders 30 , and/or pallet holders 34 may be assigned to inventory holders 50 by management module 15 based on the demand for inventory items 42 . Orders for individual inventory items 42 may be filled by shipping order holders 40 carrying individual containers 60 for the order to inventory holders 50 into which the order's inventory items 42 may be placed. In some embodiments, order holder 40 may receive inventory items 32 from other types of inventory stations before and/or after receiving inventory items 32 from inventory holders 50 . As detailed below, after accessing inventory holder 50, order holder 40 may be transported to an inventory station to receive additional items and/or to a shipping station for shipment to another facility or end user. Detailed examples of the operation of inventory system 10 are discussed below with reference to FIGS. 3-8 . In particular, techniques for facilitating order fulfillment at inventory holder 50 are discussed below with reference to FIG. An additional technique for grouping individual orders into order holders 40 .

FIG. 2 illustrates a side view of various components of an inventory system that can be populated using inventory holders 50 . In particular, FIG. 2 illustrates a particular mobile drive unit 20 transporting inventory holders 30 from inventory storage 48 to inventory holders 50 . Another mobile drive unit 20 transports the order holder 40 containing the individual containers 60 of the order to the inventory holder 50 . As shown, order holders 40 are shipped from order induction station 54 , which may be a type of station in which containers 60 are disposed on order holders 40 . At inventory holder 50 , inventory items 42 are removed from inventory holder 30 and placed into appropriate containers 60 of order holder 40 . Order holder 40 may be moved to another location along the side of inventory holder 50 to receive another inventory item 42 or may be moved to another suitable location in inventory system 10 .

Mobile drive unit 20 may transport inventory holder 30 , pallet holder 34 , and/or order holder 40 by docking and/or coupling to a particular holder and moving the holder when docked. For example, as shown, mobile drive unit 20 transports inventory holder 30 and order holder 40 , respectively. For reasons of simplicity, the shipping of the inventory holder 30 is described in more detail, but the following description applies similarly to some embodiments of the pallet holder 34 and/or order holder 40 . The mobile drive unit 20 transports the inventory holder 30 by moving under the inventory holder 30 and lifting the docking head that interfaces the portion of the inventory holder 30 . The docking head may be controlled by an actuator of mobile drive unit 20 operable to lift inventory holder 30 when docked. The docking joint of mobile drive unit 20 may couple mobile drive unit 20 to inventory holder 30 and/or support inventory holder 30 when mobile drive unit 20 is docked to inventory holder 30 . Mobile drive unit 20 may manipulate inventory holder 30 using a docking head, such as by lifting inventory holder 30 , pushing inventory holder 30 , rotating inventory holder 30 , and/or moving inventory holder 30 in any other suitable manner. The docking head of mobile drive unit 20 may also include any suitable combination of components to facilitate such manipulation of inventory holder 30 . For example, in some embodiments, the high friction portion may form all or part of a docking head that abuts a portion of inventory holder 30 when mobile drive unit 20 is docked thereto. In these embodiments, when mobile drive unit 20 actuates the docking head, friction between the high friction portion of the docking head and the surface of inventory holder 30 may induce translational and rotational movement of inventory holder 30 .

In some embodiments, mobile drive unit 20 may be capable of rotating its docking head to rotate inventory holder 30 when moving and/or when stationary. Additionally or alternatively, mobile drive unit 20 may be capable of rotating the docking head independently or as a whole as part of the movement of mobile drive unit 20 . For example, mobile drive unit 20 may rotate inventory holder 30 as mobile drive unit 20 performs a turn such that inventory holder 30 continues to face the original direction of movement. When lifting, the mobile drive unit 20 may control another actuator or an actuator that drives power to its wheels. Using wheel drives, mobile drive unit 20 may be capable of transporting inventory holder 30 when docked to lift inventory holder 30 or when mobile drive unit is undocked and/or decoupled from inventory holder 30 . As shown, mobile drive unit 20 includes a pair of stabilizer wheels in addition to motorized wheels powered by one or more actuators.

It should be noted that while a particular method of docking with inventory holder 30 is illustrated, mobile drive unit 20 may be connected to inventory holder 30 in any other manner, lift said inventory holder 30, and/or otherwise interact with it. Rather, it is docked with the inventory holder 30 such that when docked, the mobile drive unit 20 is coupled to the inventory holder 30 and/or supports the inventory holder 30 and can move the inventory holder 30 . Although the following description focuses on a particular implementation of mobile drive unit 20 and inventory holder 30 configured to interface in a particular manner, alternative implementations of mobile drive unit 20 and inventory holder 30 may be configured to accommodate mobile drive Unit 20 interfaces with any manner of moving inventory holders 30 within inventory system 10 . Additionally, mobile drive unit 20 represents all or a portion of inventory holder 30 in certain embodiments, as described below. In these embodiments, mobile drive units 20 may not be docked with inventory holder 30 until inventory holder 30 is shipped and mobile drive units 20 may each remain continuously docked with a particular inventory holder 30 .

FIG. 3 illustrates a top view of another example embodiment of an inventory system 10 capable of filling orders using inventory holders 50 . Inventory system 10 includes the various elements described above with reference to FIGS. 1 and 2 arranged in a booth. In addition to the inventory holders 50 described above, the inventory system 10 includes various inventory holders 30 and/or pallet holders 34 stored in the inventory storage 48 . Inventory system 10 also includes one or more stations, such as receiving station 52 , induction station 54 , inventory station 56 , and/or shipping station 58 . In general, orders for inventory items 42 within inventory system 10 are filled by shipping order holders 40 to inventory racks 50 and various other stations. Inventory items 42 deposited at inventory holders 50 may be used to fulfill and/or facilitate orders. In addition or alternatively, order holder 40 can be transported to inventory station 56 to receive additional inventory item 42 in inventory holder 30, wherein inventory holder 30 can be transported to inventory station 56 by mobile drive unit 20 and/or has ratio Other inventory items 42 higher cubic volume. Thus, while the quantity of high volume inventory items 42 may be less than the quantity of relatively high velocity items 42 , the total volume of high volume inventory items 42 may be higher than inventory items having higher velocities.

Inventory system 10 may represent any suitable type of order fulfillment facility. For example, inventory system 10 may represent a mail order warehouse, a distribution center for a chain retail store, a manufacturing facility, or any other facility that may utilize an inventory system to manage inventory and/or fulfill orders. In many embodiments, inventory items 42 are ordered at different order rates. Therefore, some inventory items 42 are ordered at a much higher frequency than other inventory items 42 . Likewise, some inventory items 42 may be ordered in much higher quantities than other inventory items 42 .

Receiving station 52 , induction station 54 , inventory station 56 , and shipping station 58 represent stations that include any suitable components for handling or disposing of inventory items 42 , such as scans for monitoring the inflow and outflow of inventory items 42 at remote inventory system 10 . instrument, a communication interface for communicating with the management module 15, and/or any other suitable components. A station represents a location designated for completing a specific task involving an inventory item. These tasks may include removing inventory items from inventory holders 30, directing inventory items to inventory holders 30, counting inventory items in inventory holders 30, dismantling inventory items (e.g., from pallet or case-sized groups to Individual Inventory Items), and/or handle or dispose of Inventory Items in any other appropriate manner. In some embodiments, a station may simply refer to a physical location where a particular task involving an inventory item may be completed within inventory system 10 . Alternatively or in addition, a station may represent a physical location and any suitable equipment for handling or disposing of inventory items, such as scanners for monitoring the inflow and outflow of inventory items in the inventory system 10, for communicating with the management module 15 communication interface and/or any other suitable components for communication. A station may be fully or partially controlled by an operator, or may be fully automated. In some embodiments, the operator can be an automated device. Additionally, human operators or automated operators of inventory holders 50 may be able to perform certain tasks on inventory items, such as packing or counting inventory items, as part of the operation of inventory system 10 . Additionally, human operators or automated operators of inventory holders 50 may be able to perform certain tasks on inventory items 42 , such as packing or counting inventory items 42 as part of the operation of inventory system 10 . Receiving station 52, induction station 54, inventory station 56, and shipping station 58 represent specialized stations adapted to perform the particular type of processing task that inventory system 10 supports. In general, however, some embodiments inventory system 10 may include inventory stations that are capable of handling multiple types of jobs, but are configured to handle only one particular type of job at any given time.

Receiving station 52 represents a station at which tasks associated with receiving replenished and/or replaced inventory items 42 are performed. For example, receiving station 52 may include loading bays and appropriate handling equipment to incorporate new inventory items 42 into inventory system 10 . At receiving station 52 , new inventory may be received, disassembled, disposed of, and sent into inventory system 10 , and/or any other appropriate task associated with receiving inventory items 42 into inventory system 10 .

Induction station 54 represents a station at which tasks related to assembling and/or building order holders 40 for inventory items and/or assembling containers 60 are performed. For example, induction station 54 may include appropriate materials and equipment to assemble and/or group containers 60 into order holders 40 . The interface at the guidance station 54 may provide any suitable components for assembling the container 60, such as packing slips, packaging materials, shipping labels, and materials related to other appropriate shipping and packaging tasks. In some embodiments, induction station 54 may include appropriate devices and/or interfaces to instruct operators of induction station 54 how to assemble containers 60 and/or group containers 60 into order holders 40 . For example, a given order may include a number of inventory items 42 . An indication may be provided to the operator which model of container 60 to use and into which order holder 40 to place the container 60 . A particular container 60 may be associated with a particular order directed to 54 . Thus, an "order" may refer to receiving inventory items 42 as well or alternatively when container 60 receives inventory items 42 .

In addition to or instead of inventory holder 50, inventory station 56 represents a station at which tasks related to fulfilling orders are performed. At inventory station 56 , inventory items 42 may be picked and/or placed into containers 60 of order holder 40 . The inventory station 56 may include appropriate equipment to instruct an operator to remove a particular inventory item 42 from the inventory holder 30 and to place the inventory item 42 into the container 60 of the order holder 40 . In some embodiments, inventory station 56 may interface with a transport device capable of transporting container 60 to shipping station 58 for shipping. Thus, when a particular order is completed, its associated container 60 may be removed from the order holder 40 and placed on a transport device for delivery to the shipping station 58 . Additionally or alternatively, mobile drive unit 20 may move order holder 40 out of inventory station 56 and transport order holder 40 to shipping station 58 .

Shipping station 58 represents a location at which an order may be shipped to a destination, such as an end user and/or a dedicated shipping destination for the order. For example, shipping station 58 may include loading bays and appropriate handling equipment to ship containers 60 from inventory system 10 . In some embodiments, the shipping station 58 and the receiving station 52 may be in similar or identical locations.

In operation, inventory holders 50 are used to fill orders for inventory items 42 within inventory system 10 . As inventory is received into inventory system 10 at receiving station 52 , pallets of inventory items 42 that replenish inventory system 10 may be placed onto pallet holders 34 and/or into inventory holders 30 . Selected inventory holders 30 and/or pallet holders 34 may be moved along inventory holder 50 to defined area 80 by mobile drive unit 20 . The inventory holders 30 and pallet holders 34 positioned at the defined area 80 may hold relatively high velocity and/or high volume inventory items 42 .

As the inventory system 10 receives the order, the order holder 40 is assembled with the appropriate container 60 at the lead station 54 . The mobile drive unit moves the order holders 40 along the inventory holder 50 to receive the inventory items 42 stored by the inventory holders 30 and/or the pallet holders 34 at the defined area 80 along the inventory holder 50 . If the order on a particular order holder 40 is completed after accessing the inventory holder 50 , the order holder 40 may be moved to the shipping station 58 . If the order is not fulfilled, order holder 40 may be moved by mobile drive unit 20 to one or more inventory stations 56 . As an example, if the order includes one or more relatively unpopular and/or low-volume items not stored at inventory holder 50, the order in order holder 40 may not be completed after accessing inventory holder 50. At the inventory station 56 , the particular inventory holder 30 holding the particular inventory item 42 of the order request in the order holder 40 may be transported by the mobile drive unit 20 from the inventory store 48 to the inventory station 56 . After the order is completed at picking station 56 , order holder 40 may be shipped to shipping station 58 . It should be noted that while the illustrated example shows mobile drive unit 20 transporting order holder 40 from guidance station 54 to inventory holder 50 , this is not required to be the case. In some embodiments, mobile drive unit 20 may transport a given order holder 40 to one or more inventory stations 56 or other locations within system 10 prior to transporting order holder 40 to inventory rack 50 .

Management module 15 may assign inventory holders 30 and/or pallet holders 34 to defined areas 80 at inventory holders 50 . Management module 15 may designate specific inventory holders 30 and/or pallet holders 34 to be placed at defined areas 80 of inventory holders 50 . The designation may be based on and/or responsive to the product velocity and/or volume of inventory items 42 stored in inventory holder 30 and/or pallet holder 34, respectively. In some embodiments, management module 15 may review individual orders within inventory system 10 to determine the best combination of inventory items 42 to store at inventory holder 50 . In some embodiments, the optimal combination may be based on determining the highest total amount of an order that can be fulfilled at the inventory holder 50 with a particular inventory holder 30 and/or pallet holder 34 . For example, if paper and ink cartridges are the highest volume and highest velocity items 42, respectively, and are selected for placement at the inventory rack 50, the management module 15 may select a particular high-selling printer for placement at the inventory rack 50 because many orders will Request a paper, ink cartridge, and printer combination. In some embodiments, a printer may be selected based on a determination that the printer will fulfill more of the total order at inventory holder 50 over another, more popular item.

Management module 15 may assign inventory holders 30 and/or pallet holders 34 to defined areas 80 at inventory holders 50 according to any suitable algorithm, logic, and/or decision process. For example, management module 15 may calculate a product velocity for each inventory item 42 in inventory system 10 . Management module 15 may assign inventory holder 30 and/or pallet holder 34 to defined area 80 at inventory holder 50 in response to the product velocity statistics for inventory items 42 . Some inventory systems face large fluctuations in product velocity. For example, launching a new product can spark a surge in orders for those items. As another example, holiday and/or seasonal inventory items 42 may be sold at different rates depending on the time of year. Product velocity may refer to the frequency of orders requiring a particular inventory item and/or a particular type of inventory item within system 10 within a given time period. In some embodiments, product velocity may refer to the relative quantity of each inventory item and/or each type of inventory item that an order within system 10 requires and/or is forecast to require. For example, an inventory item may have a relatively high production velocity if orders 40 within the system 10 require the inventory item more frequently than other inventory items. In some embodiments, product velocity may refer to demand for a given inventory item in a given time period. Alternatively or in addition, product velocity may simply refer to the quantity of inventory items 42 requested by orders 40 opened and/or received within inventory system 10 . In some embodiments, velocity may refer to some suitable combination of historical velocity, known demand, and expected demand.

Product volume may refer to the relative amount of inventory item 42 requested for a particular order. For example, a particular product may be ordered in bulk, such as by case and/or by pallet. For these inventory items 42 , it may be inefficient to dismantle the cases and/or pallets to place them in inventory storage 48 . Product volume may additionally or alternatively refer to the cubic volume of a particular inventory item 42 ordered within inventory system 10 . Large and/or bulky inventory items 42 may be relatively more labor intensive to integrate into inventory holders 30 than smaller sized and/or bulky items. Accordingly, the management module 15 may calculate the product volume for each inventory holder 42 and determine where the pallet holder 34 holding these items will be placed at the inventory holder 50 . In some embodiments, management module 15 may determine the product velocity and product volume for each inventory item 42 and determine whether to place inventory item 42 at inventory holder 50 based on the product velocity and product volume statistics.

Management module 15 may thus calculate product velocity and/or product volume statistics for inventory items 42 . Product velocity may be determined based on past order information, historical order trends, current orders within inventory system 10, presenting order information, known and/or expected demand, and/or forecasted future order information, sales information and/or for Any other suitable information to determine known or expected demand for inventory items 42 within inventory system 10 . Based on product velocity and/or product volume, management module 15 may determine inventory items 42 that have relatively high popularity and/or high volume. Inventory items 42 with high popularity may refer to items that are requested by multiple orders with a relatively high frequency. These inventory items 42 can often cause management module 50 to generate a correspondingly high volume of task assignments to fulfill orders for these inventory items 42 . Management module 15 may assign pallet holder 34 and/or inventory holder 30 based on determining that the assignment will reduce the amount of task assignments generated by fulfilling orders for those items using inventory holder 50 .

Management module 15 may consider each of these metrics associated with demand for inventory items 42 when selecting inventory items 42 for placement at inventory holders 50 . For example, management module 15 may determine the quantity of inventory item 42 with the highest product velocity and/or product volume to assign to inventory holder 50 . As another example, management module 15 may determine the quantity of a product with the highest known or expected demand. The selected amount of inventory holder 42 may correspond to the amount used for defined area 80 of inventory holder 30 and/or pallet holder 34 at inventory holder 50 . In some embodiments, management module 15 may compare the speed to a booking threshold to determine whether to place inventory item 42 at inventory holder 50 . For example, an inventory item 42 may be required to generate at least a predetermined amount of system activity and/or task assignments to qualify for placement at the inventory holder 50 . Additionally or alternatively, the management module 15 may determine the inventory item 42 having the highest velocity based on comparing, sorting, or otherwise analyzing the velocity of the individual products to determine the inventory item having the highest velocity.

To provide a more specific example, a particular embodiment of inventory holder 50 may include thirty defined areas 80 . Management module 15 may determine an appropriate amount of inventory items 42 to fill the thirty locations at inventory holders 50 with inventory holders 30 and/or pallet holders 34 . For example, the pallet holder 34 may hold a specific SKU's block quantity of a specific inventory item 42 . Also, certain embodiments of inventory holder 30 may carry several SKUs for each inventory item 42 . High velocity items 42 may be stored together in inventory holder 30 such that multiple inventory items 42 may be stored at one defined area 80 at inventory holder 50 in inventory holder 30 . Returning to the office supply example discussed earlier, the stock holder 30 may hold individual SKUs of popular ink cartridges, while the pallet holder 34 may hold high volume cartons with a single SKU. As a result, while there may be, for example, thirty defined areas 80 at the inventory holder 50 , the management module 15 may determine a higher quantity of inventory items 42 to store at the defined areas 80 . For example, management module 15 may designate 50-60 or more SKUs of inventory items 42 to be placed at inventory holder 50 .

It should be noted, however, that specific quantities are provided herein for purposes of illustration only, and that any suitable quantity of inventory items 42 may depend on the configuration of defined areas 80 at inventory holders 50, inventory holders 30, and/or pallet holders 34 and arrangement and placed at the inventory holder 50. For example, management module 15 may determine to store fewer inventory items 42 than exist in defined area 80, and/or may accordingly assign multiple inventory holders 30 and/or pallets that hold the same SKU or multiple SKUs of inventory items 42 Holder 34. As another example, the amount of defined area 80 at inventory holder 50 may vary depending on the system activity of inventory system 10 . Thus, while an example amount of defined area 80 has been discussed, any suitable amount of defined area 80 may be used. Additionally or alternatively, in some embodiments, inventory holder 50 may have a configurable amount of inventory holder 50 depending on the amount of highly popular and/or high volume inventory items 42 above a minimum threshold within inventory system 10 at a particular time. Defined area 80 . It should also be noted that management module 15 is operable to group high velocity items into inventory holders 30 at receiving station 52 as inventory items are received into inventory system 10 . Management module 15 may provide instructions to receiving station 52 to place specific inventory items 42 into inventory holders 30 . Accordingly, inventory holders 30 may be preconfigured to include high velocity inventory items 42 such that they may be placed at inventory holders 50 at the appropriate time.

Based on the selected inventory item 42 , the management module 15 may select the inventory holder 30 and/or the pallet holder 34 that holds the selected inventory item 42 . Management module 15 may then generate and/or issue a task assignment for mobile drive unit 20 to transport the holder to defined area 80 at inventory holder 50 . In an example embodiment in which inventory system 10 stores 5,000 SKUs of unique inventory items 42 and inventory holders 50 are arranged in thirty defined areas 80, management module 15 may select up to thirty inventory holders 30 and/or stock holders. The combination of plate holders 34 is seated at inventory holder 50 . In some embodiments, management module 15 may select the inventory holder 30 that stores the best combination of inventory items 42 to place at inventory holder 50 . Additionally or alternatively, the selection of inventory holder 30 may be based on a determination that a high order line volume is being fulfilled at inventory holder 50 . An order "line" may refer to an individual line item in that order. A line can refer to a specific SKU on an order. For example, an order for three different SKUs may have three lines. When selecting an inventory holder 30 and/or a pallet holder 34 to assign to an inventory holder 50, the management module 15 may determine the total amount of lines on the order that are expected to be fulfilled by the particular inventory holder 30 and/or pallet holder 34 . Management module 15 may assign a score to a particular inventory holder 30 and/or pallet holder 34 based on the total amount of lines completed. Management module 15 may thus assign scores to individual inventory holders within inventory system 10 and/or may determine the highest relative score for each of inventory holder 30 and/or pallet holder 34 . Based on the inventory holder 30 and/or the pallet holder 34 with the best score, the management module 15 may select the inventory holder 30 or the pallet holder 34 . When replenishing inventory holders 30 at receiving stations 52 , management module 15 may additionally or alternatively consider similar factors in determining how and which combined inventory items 42 are placed into inventory holders 30 . It should be noted that although in the example embodiment the completed bus is considered by the management module 15, the management module 15 may additionally or alternatively select a particular inventory holder 30 and/or pallet holder 34 based on the total amount of completed orders. .

The management module 15 may therefore consider the rate of product fulfillment and/or total orders when selecting inventory holders 30 and/or pallet holders 34 for inventory holders 50 . For example, based on examining known demand and historical ordering trends for inventory items 42 , management module 15 may select the combination of inventory items 42 calculated to fulfill and/or complete the most orders at inventory holder 50 . In an example, the five top selling items in inventory system 10 may be paper, ink cartridges, pencils, paper, and printers, respectively. Based on determining that the most commonly ordered combination of the above products is ink cartridges, paper, and printers, management module 15 may select paper, ink cartridges, and printers to store at inventory holder 50 accordingly.

In some embodiments, management module 15 may dispatch inventory holder 30 and/or pallet holder 34 for placement at inventory holder 50 . Management module 15 may plan a schedule to ship inventory holders 30 and/or pallet holders 34 to inventory holders 50 based on metrics associated with inventory items 42 . For example, management module 15 may determine expected demand for inventory items 42 . Based on the expected demand, the management module 15 may determine a particular inventory holder at some time in the future when the expected demand for inventory items 42 from other inventory holders is higher than the inventory item 42 in the inventory holder 30 currently at the inventory holder 50 30 should replace another inventory holder 30 at inventory holder 50 . Accordingly, management module 15 may compose a schedule on which individual inventory holders 30 and/or pallet holders 34 will be available at inventory holders 50 . Management module 15 may also determine to fulfill particular orders in the future and or delay filling orders so that inventory items 42 on various orders may be grouped together. Accordingly, at a future time greater quantities of these items 42 will be requested and the inventory holders 30 and/or pallet holders 34 holding these items at that time may be moved to the inventory holder 50 . Management module 15 may also determine how and/or when to fill orders at inventory holder 50 based on determining when to schedule shipment of individual inventory holders 30 and/or pallet holders 34 to inventory holder 50 .

In some embodiments, management module 15 may select a particular defined area 80 at inventory rack 50 to place a particular inventory holder 30 or pallet holder 34 . For example, management module 15 may select a particular defined area 80 based on the desired work distribution at inventory holder 50 . For example, inventory holder 50 may include individual operators that each remove items 42 from respective work areas in inventory holder 50 . Based on the expected or actual workload of work areas of inventory holders 50, management module 15 may assign inventory holders 30 and/or pallet holders 34 to those particular areas. Any suitable measure of workload may be used, such as picks per hour or picks per minute or other suitable measure operable to measure the level of activity at inventory holder 50 . Management module 15 may balance work distribution across the various work areas of inventory holder 50 . In other embodiments, management module 15 may randomly assign inventory holders 30 and/or pallet holders 34 with each high velocity item 42 across the work area. In some embodiments, management module 15 may assign pallet holders 34 to a particular subset of defined areas 80 while assigning inventory holders 30 to another subset of defined areas 80 . For example, the pallet holders 34 may be grouped together and/or placed at the inventory holder 50 . The pallet holders 34 may, for example, be grouped into specific work zones. As another example, inventory holders 30 may be grouped together and/or placed at inventory holder 50 , which may be in a different work area than pallet holders 34 .

Management module 15 may determine that order holders 30 and/or pallet holders 34 are optimally assigned to each defined area 80 of inventory holder 50 based on the relative velocity of inventory items within the respective inventory holder 30 or pallet holder 34 . It should also be noted that inventory holder 50 may have a configurable amount of work area depending on the total amount of work expected to be done at inventory holder 50 for a particular duration of time. For example, more operators may be assigned to inventory holders 50 , especially during heavy work, order placement, and/or system activity levels of inventory system 10 . Accordingly, inventory management module 15 may balance work distribution and/or set a rate at which orders are filled at inventory holder 50 based on the amount of operators at inventory holder 50 . Management module 15 may therefore assign more work and/or higher velocity items based on the number of operators. As discussed in more detail below, the number of operators may also affect the number and/or type of order holders 40 shipped to inventory holder 50 for order fulfillment. Taking into account the level of activity of inventory holder 50 may ensure that operators at inventory holder 50 are not overworked and/or given more tasks than is actually possible. Management module 15 may also assign an appropriate amount of work to inventory holder 50 . Additionally, distributing inventory holders 30 and/or pallet holders 34 to various defined zones 80 based on product velocity may allow for a more orderly and/or balanced flow of order holders 40 as they move along inventory holders 50 .

Within inventory system 10, the demand for inventory items 42 may change from time to time. For example, inventory items may gradually become unpopular and/or replaced by other inventory items 42 as new products and product versions are introduced. For example, a new movie released on DVD may initially be highly popular, but may decline over time and/or as new DVDs are released. Accordingly, management module 15 may be able to track product velocity and/or product inventory items 42 over time. For example, management module 15 may track known demand and/or expected demand for inventory items 42 . As the demand for inventory items 42 changes, management module 15 may issue appropriate task assignments to replace inventory items 42 stored at inventory holders 50 with other inventory items 42 based on the changes. For example, management module 15 may determine that an inventory item 42 stored at inventory holder 50 has dropped in popularity below another inventory item 42 currently stored in inventory store 48 . Management module 15 may issue an appropriate task to remove the inventory item 42 from inventory holder 50 and replace it with the inventory item currently in inventory store 48 . Additionally, as inventory holder 50 uses inventory items 42 from individual inventory holders 30 and/or pallet holders 34, the inventory items stored in these respective holders may decrease. Accordingly, management module 15 may detect, determine, and/or receive some indication of the quantity of inventory items 42 in a given inventory holder 30 and/or pallet holder 34 . The predetermined amount may, for example, indicate that the inventory holder 30 and/or the pallet holder 34 is about to run out in the amount of the inventory item 42 and has depleted the inventory item 42 . Management module 15 may therefore issue a task assignment to ship replenishment inventory item 42 to inventory holder 50 . Management module 15 may replace depleted inventory holders 30 and/or pallet holders 34 with holders storing the same type of inventory item 42 and/or may use a different inventory item having a relatively higher velocity than depleted inventory item 42 42 to replace depleted retainers.

In some embodiments, inventory holders 30 and/or pallet holders 34 may be depleted at a faster rate on the side facing inventory holder 50 . For example, the pallet holder 34 may be the first to deplete the inventory items 42 arriving within the handler of the inventory holder 50 . Thus, the side of the pallet holder 34 closest to the inventory holder 50 may be depleted, while the side facing away from the inventory holder 50 may still include an acceptable amount of inventory items 42 . Accordingly, management module 15 may receive an indication of the status of inventory holders 30 and/or pallet holders 34 that should be rotated at inventory holder 50 . Accordingly, management module 15 may issue an appropriate task assignment to mobile drive unit 20 to rotate the appropriate inventory holder 30 or pallet holder 34 . More details of specific operations and techniques for accomplishing this are discussed below with reference to FIG. 5 .

After selecting a fixed station at which inventory holders 30 and/or pallet holders 34 are placed at inventory holders 50, in certain embodiments, management module 15 may task specific mobile drive units 20 to place the selected inventory holders 30 and/or pallet holders 34 are transported along inventory holder 50 to defined area 80 . For example, management module 15 may communicate a task assignment to selected mobile drive unit 20 to identify the location of selected inventory holder 30 and/or pallet holder 34 . The management module 15 may be based on the location or state of the selected mobile drive unit 20 relative to the particular inventory holder 30 and/or pallet holder 34, an indication that the selected mobile drive unit 20 has completed a previously assigned task, a scheduled schedule, and/or or any other appropriate consideration to select the mobile drive unit 20 to assign the relevant task to. Management module 15 may plan the path that mobile drive unit 20 will take from the mobile drive unit's current location to the selected inventory holder 30 and/or pallet holder 34 . In response to assigning a task, mobile drive unit 20 may request a route to the destination of a particular inventory holder 30 or pallet holder 34 . Management module 15 may select a path between the current location of the requesting mobile drive unit 20 and the requested destination and communicate information identifying the path to mobile drive unit 20 . Management module 15 may use knowledge of current congestion, historical traffic trends, task prioritization, and/or other appropriate considerations to select the best path to take by requested mobile drive unit 20 to reach the destination. Additionally, when planning routes (or when assigning tasks), management module 15 can make informed decisions about elevators, conveyors, escalators, tunnels, and/or other conveying equipment or features of inventory system 10 to facilitate associated mobile drive units 20 in Movements within the inventory system 10.

After receiving the route from the management module 15 , the requested mobile drive unit 20 may then move across the route in a segment-by-section manner to the destination of the selected inventory holder 30 and/or pallet holder 34 . Prior to starting a particular segment, the associated mobile drive unit 20 may request permission to use the segment from the management module 15 . As a result, management module 15 may save the session for that mobile drive unit 20 . As a result, management module 15 may also be responsible for resolving competing requests for usage of a particular portion of inventory system 10 . After reaching inventory holder 30 and/or pallet holder 34, mobile drive unit 20 may be coupled, docked, or otherwise connected to the holder. For example, the mobile drive unit 20 may move under the associated holder and lift the holder using the docking head of the mobile drive unit. When moving under the holder, mobile drive unit 20 may align itself with a portion of the holder such that the central vertical axis of the docking head and/or mobile drive unit is generally aligned with the central vertical axis of the holder. After being coupled, docked, and/or connected to the holder, mobile drive unit 20 may transport the particular holder to the selected defined area 80 . At the selected defined area, mobile drive unit 20 may be unlocked, lowered, decoupled, or otherwise disconnected from inventory holder 30 . Mobile drive unit 20 may then move away from inventory holder 30 and/or indicate its availability to management module 15 to receive another task assignment.

In accordance with the above principles, each of the selected inventory holders 30 and/or pallet holders 34 may be transported by the mobile drive unit 20 to the inventory holder 50 . It should be noted, however, that while specific examples of how to transport inventory holders 30 and pallet holders 34 to inventory holders 50 are discussed, any suitable method may be used. For example, in some embodiments, inventory holders 30 may be transported by mobile drive unit 20 to inventory holders 50, while pallet holders 34 may be transported by some other transport means, such as by a crane, forklift, conveyor, or capable of transporting inventory items. 42 pallets for other industrial mobile equipment. In some embodiments, management module 15 may be able to utilize one or more drift locations in conjunction with transporting inventory holders 30 and/or pallet holders 34 to inventory holders 50 . A more detailed discussion of drift locations and how they may be used to fulfill orders at inventory holder 50 is discussed below with reference to FIG. 5 .

During operation of inventory system 10 , management module 15 may receive orders requesting individual inventory items 42 at various times. To fulfill an order for inventory items 42 received by management module 15 , management module 15 may place two or more orders onto order holder 40 . The order holder 40 can be arranged, for example, at the guidance station 54 . At the induction station 54 , one or more orders may be grouped into containers 60 and arranged on the order holder 40 . The containers 60 may be placed on the order holder 40 based on any number and type of factors, including the size of the containers 60, the type of inventory items 42 desired to be received in the containers 60, the number of inventory items 42 receiving an order from the inventory holder 50, capacity, or other appropriate factors. Additionally or alternatively, management module 15 may determine to group individual orders based on expected fulfillment of the order within a given inventory holder 34 at inventory holder 50 .

Management module 15 may determine to group orders associated with containers 60 into order holders 40 in any suitable manner. For example, management module 15 may examine outstanding orders within inventory system 10 to identify one or more inventory items 42 in response to an order for one or more inventory items. The management module 15 may determine which inventory holder 30 and/or pallet holder 34 stores the inventory items 42 . Management module 15 may determine whether inventory items 42 on the order are stored at inventory holders 50 and/or in inventory storage 48 . Management module 15 may group orders based on determining that one or more inventory items 42 for different order requests are each located at defined area 80 at inventory holder 50 . An order may have an associated container 60 to receive the order's inventory items 42 . For example, container 60 may be a suitably sized pallet box or other container suitable for shipping, as described above. Accordingly, the order holder 40 may be arranged such that it holds respective groups of containers 60 associated with orders designated to receive inventory items 42 at various locations along the inventory holder 50 .

Management module 15 may be capable of arranging various configurations of order holders 40 depending on outstanding orders and/or various activity levels of inventory system 10 . For example, management module 15 may arrange order holders 40 to include orders for inventory items 42 that are all located at inventory holders 50 when those order holders 40 are shipped to inventory holders 50 to be received on orders in order holders 40 All orders placed in the order holder 40 can be fulfilled at the inventory holder 50 while stocking items 42. Management module 15 may also arrange order holder 40 to include inventory items 42 located at inventory holders 50 and orders for inventory items 42 stored in inventory storage 48 . These order holders 40 may be partially completed at inventory racks 50 and may be transported to various inventory stations 56 so that inventory items 42 in inventory storage 48 may be transported to those inventory stations 56 by mobile drive unit 20 . Management module 15 may also arrange order holder 40 to include orders for inventory items 42 located individually in inventory storage 48 . These order holders can be fulfilled at inventory station 56 . These configurations of order holders 40 may be referred to as inventory-only rack order holders 40 , hybrid order holders 40 , and/or inventory-only order holders 40 , respectively.

Management module 15 may determine the number and/or configuration of order holders 40 to assemble based on any suitable considerations. For example, management module 15 may thus take into account the activity level and/or the work assignment of the operators of inventory holder 50 and/or the overall workload of inventory holder 50 . If the management module 15 determines that the workload of the inventory holder 50 is above a predetermined level, the management module 15 may determine to form a hybrid order holder 40 and/or a depot-only order holder 40 . Workload may refer to assigned picks per hour, assigned workload, or other suitable metric for measuring the activity level of inventory holder 50 . For example, an operator of inventory holder 50 may be capable of operating inventory holder 50 at a predetermined and/or maximum power rate. Management module 15 may assign workloads to inventory holders 50 that are calculated such that operators of inventory holders 50 operate at substantially predetermined and/or maximum work rates. In some embodiments, the maximum work rate may be used to determine an optimal and/or maximum work amount that may be assigned to inventory holder 50 . Management module 15 may determine to reduce and/or increase work at inventory holder 50 to achieve optimal and/or maximum work load. Based on the determination, management module 15 may select the number and configuration of order holders 40 . If, for example, the workload at inventory holder 50 is above the minimum value but below the maximum value, management module 15 may determine to place a mix of hybrid order holders 40 and/or inventory holder-only order holders 40 based on a predetermined schedule. The predetermined schedule may be determined based on trying to balance the work, keeping the workload above a minimum and below a maximum, the number of operators at the inventory holder 50, and/or any other suitable factors. If the workload at the inventory holder 50 is below the minimum, the management module 15 may determine to assemble an order holder 40 consisting solely of inventory holder-only order holders 40 (if possible) Inventory items 42 in inventory storage 48 arrange order holder 40 .

The management module 15 may sequence the orders and/or the arrangement of the order holders 40 according to the above principles. For example, management module 15 may prioritize orders that can be fulfilled at inventory holder 50 over orders that consist of relatively greater velocity or less popular items that may be located in inventory storage 48 . Alternatively or additionally, individual lead stations 54 may be designated for handling orders for less popular inventory items 42 . Management module 15 may direct order holders 40 to fit at other directing stations for these other items. In some embodiments, management module 15 may arrange to include inventory stored by inventory holder 50 but may still decide to fulfill these orders from inventory station 56 rather than at inventory holder 50 based on various factors, such as the activity level considerations discussed. An order holder 40 for items 42 .

The management module 15 may additionally or alternatively consider where the particular inventory item 42 requested by each order is stored on the inventory holder 50 when placing the order holder 40 . For example, management module 15 may balance workload distribution across various work areas of inventory holder 50 . Management module 15 may attempt to even distribute the amount of inventory items 42 received by a particular order holder 40 as it moves along various locations at inventory holder 50 and/or balance the flow of order holders 40 moving to inventory holder 50 . To illustrate, rather than receiving five inventory items 42 from one inventory holder 30 at one defined area 80 , the management module 15 may arrange orders containing five different inventory items 42 at five different defined areas 80 along the inventory rack 50 . In some embodiments, the SKU for a particular inventory item 42 may be stored in two different locations. The management module 15 may determine to fulfill an order in an order holder 40 requesting the same SKU using two different inventory holders 30 stored at the inventory holder 50 to balance the work flow of the inventory holder 50 and/or to prevent A sharp increase in the activity level of the inventory holder 50 at the location of the inventory holder 50 . However, it should be noted that this example is for illustration purposes only. Management module 15 may distribute and/or balance work at inventory holders 50 in any suitable manner.

Management module 15 may determine any suitable combination of containers 60 to place in order holder 40 to minimize the amount of order holder 40 shipped to inventory holder 50 . In some implementations, management module 15 may determine to group orders based on reducing the total number of trips required by mobile drive unit 20 . As discussed above, task assignments to mobile drive units 20 by management module 15 may involve traversing a particular path to a destination. When order holders 40 are shipped to inventory holders 50 , mobile drive unit 20 may need to transfer order holders 40 from lead station 54 to inventory holders 50 . Mobile drive unit 20 may then transport order holder 40 to inventory station 56 and/or shipping station 58 . Orders may be grouped into order holders 40 to minimize the amount of travel required by mobile drive units 20 and/or reduce and/or minimize the overall length of travel required by mobile drive units 20 . Accordingly, management module 15 may attempt to minimize the overall travel of mobile drive unit 20 when placing order holder 40 .

After order holders 40 are assembled, mobile drive unit 20 may transport order holders 40 to dock racks 50 within inventory system 10 and/or to other destinations. Mobile drive unit 20 may ship order holder 40 in response to appropriate task assignments from management module 15 . Management module 15 may assign tasks to mobile drive units 20 to deliver order holders 40 to inventory holders 50 using any of the tasking and/or routing techniques described above. Mobile drive unit 20 moves order holder 40 along inventory holder 50 . As the order holder 40 moves along the inventory holder 50, the order holder 40 moves along the side of the inventory holder 50 relative to the defined area 80 where the inventory item 42 is stored in the inventory holder 30 and/or the pallet holder 34. The location receives inventory items 42 . In some embodiments, operators at inventory holders 50 may transfer inventory items 42 from inventory holders 30 and/or pallet holders 34 into appropriate receptacles 60 of order holders 40 . Management module 15 may activate indicators, such as lights or other visual indicators, at inventory holders 50 to indicate where the operator expects order holders 40 to slow down and/or stop at various locations where inventory items 42 are to be received. Alternatively or additionally, the management module 15 may communicate appropriate information to the inventory holder 50 instructing the operator which inventory item 42 to pick and place into which container 60 to place said inventory item 42 of the order holder 40 .

Order holder 40 may be transported along a side of inventory holder 50 opposite defined area 80 in a manner that facilitates operator interaction with order holder 40 . In some embodiments, the order holders 40 may be transported along the side of the inventory holder 50 such that the operator and a given order holder 40 move together in an initial direction until the operator reaches the end of the operator's particular work area. When a given order holder 40 arrives at the next work area, the operator at the next work area can begin placing items into the order holder 40 as appropriate. The operator of the first zone may then return to the far end of the zone and then continue to place inventory items 42 into the new order holder 40 as it moves along the inventory holder 50 in the original direction. The arrival of the order holder 40 to the start of a particular work area may be timed based on when the operator returns to the start of that work area. A detailed discussion of how the order holder 40 moves along the inventory holder 50 and how an indicator at the inventory holder 50 may instruct the operator to ship the inventory item 42 will be discussed below with reference to FIG. 5 .

After the appropriate inventory item 42 is received into the container 60 of the order holder 40 , the mobile drive unit 20 may proceed to move the order holder 40 to the appropriate location within the inventory system 10 . If the order is not complete, the order holder 40 may be moved by the mobile drive unit 20 to the appropriate stocking station 56 so that additional items 42 may be received. While at inventory station 56 , additional inventory items 42 may be received by an order in order holder 40 . Additionally or alternatively, inventory station 56 may prepare containers 60 in order holders 40 for shipment to end users and/or shipping destinations. For example, the operator may perform order fulfillment tasks such as adding protective packaging material to the container 60 and/or closing, tapping, sealing, and/or performing other tasks to prepare the container 60 for shipping. Once the order is completed, the order holder 40 can be transported by the mobile drive unit 20 to the shipping station 58 for shipping, however, it should be noted that in some embodiments, the inventory station 56 can be used to complete and ship the order. Additionally or alternatively, shipping station 58 may perform the order fulfillment tasks described above.

While order holder 40 is positioned at inventory station 56 , management module 15 may locate additional inventory items 42 within inventory storage 48 . The management of the mobile drive units within the inventory system 10 is tasked with transporting the particular inventory holder 30 to the inventory station 56 for the remaining inventory items 42 needed for the order of storage containers 60 . For example, any suitable technique may be used at inventory station 56 to facilitate transfer of items from inventory holders 30 located in inventory storage 48 to containers 60 of order holders 40 . After the order is fulfilled by one or more inventory stations 56, the order holders 40 and/or containers 60 may be moved and/or shipped to a shipping station 58 for shipment to an end user and/or a shipment destination. Mobile drive unit 20 may transport order holder 40 to shipping station 58 for final shipping preparation as discussed above.

FIG. 4 illustrates a top view of another example embodiment of an inventory system 10 capable of filling orders using inventory holders 50 . In FIG. 4, inventory system 10 is arranged in a plurality of inventory holders 50a, 50b, and 50c. When used in conjunction, inventory holders 50a - 50c are capable of fulfilling substantially all orders for inventory items 42 stored in inventory storage 48 of inventory system 10 . As shown, inventory system 10 may operate in a manner generally similar to that described above with reference to FIG. 3 , with any suitable modifications made to support a number of inventory holders 50 .

Inventory storage 48 may be disposed between inventory holders 50 such that mobile drive units may be able to swap out inventory holders 30 and/or pallets 34 based on product velocity and/or volume according to the techniques above. Additionally, receiving station 52 may be arranged such that the path traveled by order holders 40 within inventory system 10 is shortened. Accordingly, receiving stations 52 may be located near areas of inventory storage 48 that store inventory items 32 received by those particular receiving stations 52 . As shown, receiving station 52 is located between inventory holders 50 such that it is accessible by mobile drive unit 20 operating near a particular area of inventory storage 48 . Additionally or alternatively, receiving station 52 may be arranged such that operators may have a path to and from inventory holder 50 without intersecting the path of mobile drive unit 20 . It should be noted, however, that while a particular arrangement of inventory holders 50, induction stations 54, shipping stations 58, and receiving stations 52 is illustrated, any particular geometry and layout of inventory system 10 may be suitable and may be used. Furthermore, any suitable number and/or type of inventory holders 50 may be used.

In operation, after mobile drive unit 20 accesses inventory rack 50a, mobile drive unit 20 may ship order holder 40 to inventory rack 50b if order holder 40 has an order requesting inventory item 42 to be stored at inventory rack 50b. 50b. After receiving inventory items 42 from inventory holder 50b and after accessing inventory 50b, mobile drive unit 20 may transport order holder 40 to inventory holder 50c. Alternatively, if order holder 40 requires inventory item 42 at inventory rack 50b, mobile drive unit 20 may proceed to inventory rack 50c without accessing inventory rack 50b. In some embodiments, if the order in order holder 40 receives all requested items and/or is ready to complete for shipment after accessing one or more of these inventory holders 50, then mobile drive unit 20 may access the inventory Racks 50a and/or 50b then proceed to shipping station 58 . Accordingly, in some embodiments, the order holder 40 may only access the inventory holders 50a, 50b, 50c that have the inventory items 42 of the order request in the order holder 40 . Additionally or alternatively, the management module 15 is operable to balance the distribution of work among each inventory holder 50a-50c in the inventory system 10 such that the amount of work exceeding a maximum amount and/or falling below a minimum amount is avoided. For example, inventory holders 50a and 50b may each store a particular inventory item 42 . Management module 15 may determine that a particular order holder 40 should receive a particular inventory item 42 from inventory holder 50b rather than inventory holder 50a based on determining that the workload at inventory holder 50b is lower than the workload at inventory holder 50a, noting that, for purposes of illustration, To discuss a specific example of work distribution balancing, management module 15 may determine to balance the workload at inventory holders 50a-50c in any suitable manner. Management module 15 may also assign inventory holders 30 and/or pallet holders 34 to each defined area 80 of each inventory holder 50 according to the previously discussed balancing techniques.

FIG. 5 illustrates a particular technique for fulfilling an order using inventory holder 50 in inventory system 10 . Inventory system 10 may include one or more drift locations 90A through 90D. Management module 15 is operable to designate specific areas within inventory system 10 as drift locations 90 . Accordingly, management module 15 may use one or more drift spaces in conjunction with inventory holder 50 to facilitate order fulfillment. FIG. 5 also illustrates the technique of rotating the inventory holder 30 located in a defined area 80 at the inventory holder 50 . Finally, FIG. 5 illustrates the ability of inventory holder 50 to activate indicator 64 to facilitate movement of operators within their respective work zones. The indicator 64 may indicate that a given order holder 40 is to be stopped relative to the position of the inventory holder 30 and/or the pallet holder 34 . Each of these techniques will be discussed in turn.

Inventory system 10 may facilitate fulfillment of orders at inventory holders 50 according to the order packaging arrangement using a technique referred to herein as "drifting." Drifting may allow components of inventory system 10 to be moved or otherwise positioned toward a particular destination during the completion of a particular task involving that element in order to reduce travel time to the associated destination. In the context of facilitating fulfillment of orders at inventory holder 50 , drifting may be used to collect inventory items 42 near inventory holder 50 so that they are nearby when defined area 80 becomes available. It may be expected that one or more order holders 40 will require drifting inventory items 42 in the future. Accordingly, the time required to replace and/or replace inventory items 42 deposited at inventory holders 50 may be reduced according to less complex techniques.

A "drift" location 90 represents a location near an inventory station in a warehouse where a mobile drive unit designated to carry inventory holders "drifts" until the appropriate time to pack the inventory needed for an order. Drift location 90 may serve as a location where popular inventory items 42 may be swapped into and out of defined area 80 along inventory holder 50 at specific times and/or as needed. For example, the drift position 90 may be used to hold an inventory holder 30 near the inventory holder 50 that has an inventory item 42 that is low and has recently been replaced by another inventory holder 30 that stores higher velocity inventory items 42 . Management module 15 may achieve various efficiencies by keeping order holders 40 near inventory holders 50 as they arrive at inventory holders 50 , such as by enabling placement in one of defined areas 80 . Accordingly, some embodiments of system 10 may utilize drift to anticipate tasks to be accomplished and locate relevant components to reduce the time required to complete the expected tasks. Drifting reduces congestion due to the use of less sophisticated techniques. Utilizing drift locations 90 may allow fulfillment of specific orders that involve several tasks being completed by inventory system 10, while reducing the time it takes inventory system 10 to complete these tasks and improving system throughput. Drifting may additionally or alternatively allow for more efficient use of the limited physical area within inventory system 10 . An example embodiment of inventory system 10 including drift locations 90 is described herein.

Management module 15 may determine to send a particular inventory holder 30 and/or pallet holder 34 to a particular drift location 90 in response to detecting the first trigger event(s). In particular embodiments, the associated element may remain in a particular drift space 90 or a particular set of drift locations 90 until a second triggering event (or events) occurs. After the second trigger event occurs, the element can then move toward the associated system resource to complete the task. In certain embodiments, the space may be statistically designated as the drift location 90, while in an alternative embodiment, depending on the resources required by the inventory system 10, the availability of the space 74, and/or other appropriate considerations, the space may be dynamically designated as Drift position 90. As described further below, drift locations 90 may be utilized in various ways to improve throughput or otherwise increase system efficiency of particular embodiments of inventory system 10 , including but not limited to facilitating fulfillment of orders at inventory holders 50 .

Management module 15 may determine to move inventory holder 30 and/or pallet holder 34 from inventory holder 50 in response to a first trigger event, such as determining that the amount of inventory in the respective holder has dropped below a predetermined amount. In some implementations, management module 15 may determine that inventory item 42 of a newly depleted inventory holder 30 has dropped below other inventory items 42 in popularity. Drift locations 90 may thus be used to hold inventory holders 30 and low-stock items 42 near inventory holders 50 so that they may be used as needed to fulfill orders for inventory items 42 . As another example, a particular stock holder 30 may contain stock items 42 that are reduced in product velocity and the more popular items moved to the defined area 80 where the stock holder 30 was previously seated. Rather than holding these inventory items 42 to inventory storage 48 with its inventory holder 30 , for example, the inventory holder 30 may be moved to a drift position 90 so that it is available near the inventory holder 50 for future orders. However, management module 15 may determine that inventory item 42 is still relatively more popular than other items stored in inventory store 48 and/or expected for near future orders. If these inventory holders 30 are needed in the near future, greater efficiencies may be realized by leaving these inventory holders 30 near the inventory holder 50 rather than moving the inventory holders 30 to the inventory storage 48 .

As shown, several drift locations 90 a - 90 d are positioned near inventory holder 50 . As shown, a particular inventory holder 30a may move to a drift position 90a in response to management module 15 detecting one of the aforementioned triggering events, which may cause management module 15 to transfer inventory holder 30a from defined area 80a to drift space 90a .

As the other inventory holders 30 drift, inventory holder 30a may drift at one or more of drift locations 90a-90d. In some embodiments, drift locations 90 a - 90 d may be used as a random access buffer for inventory keeper 30 . Accordingly, inventory holders 30 may be assigned to randomly available drift positions 90a-90d. Inventory holder 30 may remain in assigned drift position 90a - 90d until a second triggering event occurs. Additionally or alternatively, drift positions can be used as a continuous queue. Inventory holder 30 may drift through positions 90a through 90d as successive positions become available. It should be noted, however, that while the drift locations 90a-90d are illustrated as being adjacent to each other, this need not necessarily be the case. In some embodiments, drift positions 90 may be contiguous and/or separated from each other. Furthermore, in some embodiments, drift locations 90 may be suitably located in groups of dispersedly positioned drift locations 90 . In response to detecting the second trigger event, management module 15 may determine to move inventory holder 30a back along inventory holder 50 to defined area 80 . For example, inventory holders 40 that require inventory holders 30a to store inventory items 42 may be shipped to inventory holder 50 and/or are expected to be shipped to inventory holder 50 in the near future. As shown, the present technique may suitably utilize several inventory holders 30 a - 30 c to drift each holder about inventory holder 50 . Accordingly, these inventory holders 30 will be available for placement at the defined area 80 more quickly than would otherwise be done using complex techniques.

As another example of a triggering event that causes management module 15 to determine a drifting inventory holder 30, it may be determined that inventory holder 30b at desired defined area 80b is depleted and/or that inventory items 42 are about to be depleted, and therefore, inventory holder 30c Can be transported to drift location 90d with the expectation that inventory holder 30c will replace inventory holder 30b as soon as possible. Inventory holder 30c may, for example, store additional inventory items 42 of the same SKU of the SKU stored by inventory holder 30b. As another example, it may be desirable that inventory items 42 of desired inventory 30b fall below a certain relative product velocity and items 42 in inventory holder 30c may have a relatively higher product velocity. Inventory items 30c may be made ready in drift position 90d to replace those items in inventory holder 30b as appropriate.

In some embodiments, management module 15 may determine to drift one or more order holders 40 . Management module 15 may determine to drift one or more order holders 40 in response to detecting the first trigger event. The first trigger event may, for example, be a determination that the workload of inventory holder 50 exceeds a predetermined and/or maximum amount. For example, all available positions at inventory holder 50 may be occupied by other order holders 40 . Management module 15 may instruct mobile drive unit 20 to transport order holder 40 to drift location 90 proximate to inventory holder 50 . In response to the second trigger event, management module 15 may instruct mobile drive unit 20 to transport order holder 40 from drift location 90 away from inventory holder 50 . For example, the second trigger event may determine that the workload of inventory holder 50 is below a predetermined and/or maximum amount. Other examples of triggering events that may trigger drift of an order holder 40 include determining that an inventory holder 30 and/or a pallet holder 34 with an inventory item 42 requested by one or more orders in the order holder 40 is not in stock bracket 50, but will be at stock bracket 50 in the near future. For example, the inventory holder 30 with the requested inventory item 42 may itself be in the drift location 90 . As another example, as discussed in more detail below, the pallet holder 34 may undergo a process of rotational manipulation. Accordingly, management module 15 may determine to drift order holders 40 until the desired inventory holders 30 and/or pallet holders 34 are located at inventory holders 50 . Additionally, if the management module 15 determines that additional inventory items 42 requested by the order holder 40 will be shipped to the inventory holder 50 in the near future, the order holder 40 may be dispatched after receiving the inventory item 42 at the inventory holder 50 to the drift position. The order holders 40 may first receive all available inventory items 42 for an order request in those order holders 40 before moving to the drift location 90 . However, in some embodiments, management module 15 may determine where to send order holder 40 to inventory store 48 in some cases. For example, order holder 40 may request inventory items 42 that are only available at inventory holder 50 but are not scheduled for shipment to inventory holder 50 until after an amount of time greater than a predetermined threshold has elapsed. Alternatively or in addition, management module 15 may select particular order holders 40 to ship to inventory holder 50 based on an amount of time since those order holders 40 were assembled at induction station 54 .

FIG. 5 also illustrates the technique of rotating the pallet holder 34 a seated in a defined area 80 at the inventory holder 50 . First, the management module 15 may determine to rotate the pallet holder 34a in response to any suitable triggering event. For example, the operator of the inventory holder 50 may indicate that the inventory item 42 on the side closest to the inventory holder 50 is low, while other inventory items on the other side of the pallet holder 34a are still available (but the operator may not be able to access them). up to). Accordingly, management module 15 may instruct mobile drive unit 20 to move to pallet holder 34a and/or perform a rotational maneuver. The mobile drive unit 20 is movable under the pallet holder 34a. Mobile drive unit 20 may then be docked, coupled, or otherwise connected to pallet holder 34a. Mobile drive unit 20 may then move pallet holder 34a away from the inventory holder such that pallet holder 34a may rotate. The pallet holder 34a can be moved away by an appropriate amount so that there is only enough room for the pallet holder 34a to be selected without colliding with other inventory holders 30 and/or pallet holders 34 located at the inventory holder 50 . As shown in step 2, the pallet holder 34a can choose 180 degrees. In step three, the pallet holder 34a can be moved back to the inventory holder 50 . Although illustrated as being rotated 180 degrees, the pallet holder 34a may be rotated any suitable amount, including 90 degrees, 270 degrees, or any other suitable amount.

FIG. 5 also illustrates certain techniques for moving inventory holder 40 along inventory holder 50 to facilitate the efficiency of one or more operators of inventory holder 50 . As shown, inventory holder 50 includes two zones 100 and 102, one for each operator. As shown, zones 100 and 102 may change and/or overlap based on the operation of inventory holder 50 and the arrival of order holder 40 . The operator may be instructed to move in an initial direction to pick inventory items from the inventory holder 30 and/or the pallet holder 34 as the order holder 40 moves along the inventory holder 50 . The initial direction may be the same direction that the order holder 40 is moving along the inventory holder 50 . In the illustration, the inventory holder 40 moves from left to right and the operator moves primarily from left to right. Once the operator reaches the end of zone 100 while moving in the initial direction, the operator may be instructed to return to the starting point in zone 100 illustrated as the furthest left point of inventory holder 50 . After returning to the starting point of zone 100 , the operator may begin moving in the original direction again to satisfy more requests to move inventory items 42 into containers 60 of order holder 40 . The order holder 40 is movable to a position opposite the defined area 80 of the particular stock holder 30 that holds the order requested inventory items 42 in the order holder 40 . Once the order holder 40 is in place, the order holder 40 may be slowed and/or stopped until the operator completes the transfer of the inventory item 42 into the appropriate container 60 of the order holder 40 . The order holder 40 may receive inventory items 42 from the operator as the operator moves in the initial direction. Similar patterns can be used for operators in other zones, including zone 102 . In some embodiments, the arrival of the order holder 40 may be timed such that the order holder 40 arrives as the operator moves along the zone 100 in an initial direction. Alternatively or in addition, the manipulator of inventory holder 50 may be moved in both directions as appropriate to move to order holder 40 ready to receive inventory item 42 .

As shown, the indicators 64 are disposed at various points along the inventory holder 50 opposite a defined area 80 of the inventory holder 30 and/or the pallet holder 34 . As the order holder 40 moves along the inventory holder 50 , an indicator may be activated to indicate where the operator expects the inventory holder order holder 40 to stop or slow down along the inventory holder 50 . Indicators 64 may generally be positioned opposite each defined area 80 . It should be noted that while illustrated as a scatter indicator 64, any suitable method of communication, which would be the order holder 40, would be used. For example, display screens may be placed at various locations along the inventory holder 50, indicating where the operator 50 expects the order holder 40 to stop and/or slow down and may additionally indicate where 34 Which item to move 42.

In the illustrated embodiment, the order holder 40a will stop when approaching the indicator 64a. Management module 15 may thus activate indicator 64a. The operator may travel to indicator 64a. At indicator 64a, the operator may place the appropriate inventory item 42 from the inventory holder 30 opposite indicator 64a into the appropriate container 60 of order holder 40a. In some embodiments, an indicator 64a or some other piece of equipment at the inventory holder 50 may instruct the operator to pick a particular inventory item 42 and/or instruct the operator to place a particular inventory item 42 into a particular receptacle 60 of the order holder 40a. middle. For example, the indicator may display lights or other visual indicators indicating which container 60 will receive inventory items 42 from a given inventory holder 50 . Similarly, in the second work zone 102, other operators may receive a signal from the indicator 64b indicating that the order holder 40b will stop and/or slow down as it approaches the indicator 64b. According to these techniques, orders can be fulfilled at inventory holder 50 in a more efficient manner than would otherwise be possible.

Mobile drive units 20 are operable to avoid collisions with other mobile drive units 20 while moving along inventory holder 50 . For example, as order holder 40a moves along inventory rack 50 , management module 15 may determine the next location to receive inventory item 42 . The management module 15 may determine whether another order holder 40b is blocking the path between the order holder 40a and the next location. If order holder 40b is unobstructed and there are no other obstructions, management module 15 may activate indicator 64a at the next location and mobile drive unit 20 may transport order holder 40a to indicator 64a. If order holder 40b does so, management module 15 may determine the destination of order holder 40b. Indicator 64a may be activated if the destination of order holder 40b is past the next location of order holder 40a. Otherwise, the management module 15 may delay activation of the indicator 64a until the order holder 40b no longer has blocking destinations along the path of the order holder 40a and/or clears the desired path of the order holder 40a. This method also avoids operator confusion as the operator will know that the activation of the indicator 64 corresponds to the previous order holder 40 .

FIG. 6 is a flowchart illustrating an example method 600 of filling an order using an inventory holder. Method 600 begins at step 602 where management module 15 selects an inventory holder 30 and/or pallet holder 34 to be placed at inventory holder 50 . Selection can be made according to any suitable algorithm, logic and/or decision process. Further details of how step 602 may be implemented are discussed in more detail below with reference to FIG. 7 .

At 604, after selecting the appropriate inventory holder 30 and/or pallet holder 34 to place at the inventory holder 50, the management module 15 instructs the mobile drive unit 20 to transport the inventory holder 30 and/or pallet holder 34 to the inventory Bracket 50. Mobile drive unit 20 may retrieve and transport the selected inventory holder 30 and/or pallet holder 34 to the appropriately defined area 80 of inventory holder 50 according to the techniques discussed above.

At step 606 , management module 15 may determine whether defined area 80 at inventory holder 50 is still usable. If the additional defined area 80 remains to be filled, the method may return to step 602 where additional inventory holders 30 and/or pallet holders 24 may optionally be placed on the inventory holding rack 50 . It should be noted that although shown sequentially, management module 15 may select all inventory holders for each defined area 80 substantially simultaneously. In addition, steps 602 through 606 may occur as often as necessary and/or continuously within inventory system 10 as inventory items 42 change. Additionally, in some embodiments, management module 15 may determine to leave some defined areas 80 unpopulated. Management module 15 need not designate all defined areas 80 at inventory holders 50 for inventory holders 30 and pallet holders 34 . For example, management module 15 may leave some defined areas unpopulated due to workload constraints, overall system activity, or various other factors. Alternatively or additionally, one or more defined areas 80 may be designated as locations for waste holders 36 or other waste receptacles. In some embodiments, the waste holder 36 and/or waste container are operable to be carried by the mobile drive unit 20 . Accordingly, packaging material and/or other waste products resulting from waste from inventory holder 50 may be placed into waste holder 36 at defined area 80 . At the appropriate time and/or when full, the waste holder 36 may be transported away from the inventory holder 50 by the mobile drive unit 20 .

At step 608 , the management module 15 may receive an order for each inventory item 42 . For example, inventory system 10 may receive orders at any time. It should also be noted that orders may be received before, during, and after the process of assigning inventory holders 30 and/or pallet holders 34 to the defined area 80 described in steps 602 to 606 . Accordingly, step 608 may be performed sequentially and/or in parallel with steps 602-606. Additionally, orders may be received when new inventory holders 30 and/or pallet holders 34 are appropriately reassigned to the defined area 80 .

In step 610 , management module 15 may determine whether one or more requests for inventory items 42 on the order at inventory holder 50 are satisfied. For example, based on the allocation and/or total workload at inventory holder 50 , management module 15 may determine all and/or a portion of the order to fill inventory station 56 but not inventory holder 50 . In some embodiments, management module 15 may determine to fill the partial order at inventory station 56 and the partial order at inventory holder 50 . Management module 15 may also determine the sequence of inventory stations 56 and/or inventory holders 50 to visit for an order when filling the order. The sequence may be any suitable sequence, including visiting one or more inventory stations 56 first or visiting one or more inventory holders 50 first. Alternatively or additionally, the management module 15 may determine the appropriate type of order holder 40 to place. For example, the order holder 40 may be arranged as an inventory rack only order holder 40 , a hybrid order holder 40 and/or a stock station only order holder 40 . The decision process of how to process a given order can be made in accordance with any of the aforementioned work balancing and/or allocation techniques. In some embodiments, management module 15 may determine where to send order holder 40 while order holder 40 is in the process of receiving inventory items 42 . For example, management module 15 may determine to fill an order and/or a portion of an order on holder 40 with inventory items 42 located at inventory holder 50 . Instead, management module 15 may determine to fill orders and/or portions of orders on order holders 40 at inventory stations 56 . After receiving these inventory items 42 , management module 15 may determine whether to fill additional orders and/or additional order lines on order holder 40 with inventory items 42 at inventory racks 50 and/or inventory stations 56 . As an example, the management module 15 may determine where to send the order holder 40 and/or determine that the inventory item 42 will be located in the inventory system 10 based on checking an open line on the order holder 40 for an order requesting an inventory item 42 that has not been received. where. Additionally or alternatively, management module 15 may determine fill orders at one or more inventory racks 50 and inventory stations 56, but may decide to do so before instructing mobile drive unit 20 to ship order holder 40 to one or more of these locations. Wait for a predetermined amount of time. For example, based on one or more of the triggering events discussed above, management module 15 may determine to ship order holder 40 to a drift location before continuing to fill order holder 40 . As another example, management module 15 may determine to delay assembling a particular order based on one or more conditions of inventory system 10 . Management module 15 may therefore also consider how long an order has been pending when determining whether to fill an order and/or fill another order first.

At step 612 , management module 15 may determine the placement of order holders 40 to be shipped to inventory holder 50 to fill the order. For example, management module 15 may determine to group two or more orders into a particular order holder 40 such that two orders can be fulfilled by one order holder 40 . Further details of how step 612 may be accomplished in accordance with an example operation of inventory system 10 are discussed below with reference to FIG. 8 . At step 614 , after order holders 40 are deployed, management module 15 may instruct one or more mobile drive units to transport order holders 40 to inventory holders 50 so that items may be received into containers 60 of order holders 40 . It should be noted that step 612 may be performed based on the management module determining the type of order holder 40 deployed at step 610 . Furthermore, while illustrated as being performed when management module 15 determines to fill all and/or a portion of the order at inventory holder 50 , step 612 may be performed even when management module 15 determines to fill the order at inventory station 56 at step 624 . For example, management module 15 may determine to place the order into stock-only station holder 40 and/or may group the order on order holder 40 with other orders designated for filling at stock station 56 .

At step 616 , mobile drive unit 20 moves order holder 40 to a position along inventory holder 50 such that order holder 40 can receive inventory item 42 according to the order associated with each container 60 held. Container 60 may receive inventory item 42 according to its associated order at step 618 . For example, the operator at the inventory holder 50 may transfer the appropriate inventory item 42 into the appropriate container 60 of the order holder 40 at the point where the order holder 40 is stopped and/or slowed down.

At step 620 , after receiving inventory items 42 at inventory holder 50 , management module 15 may determine whether the order in order holder 40 is complete. If the order is complete, then at step 622 the management module 15 may instruct the mobile drive 20 to transport the order holder 40 to the inventory station 56 and/or the shipping station 58 for shipment preparation and/or shipment to the final destination. If one or more orders on the order holder 40 are outstanding, the method may proceed to step 610, where the management module 15 may determine whether to fill the order holder 40 at the inventory rack 50 and/or at the inventory station 56. The remaining open lines of the order. For example, management module 15 may determine at step 610 that additional items requested by the order on order holder 40 will be available for inventory holder 50 in the near future. Management module 15 may thus instruct mobile drive unit 20 to ship order holder 40 into drift location 90 near inventory holder 50 and/or wait for the inventory to become available. As another example, management module 15 may determine at step 610 that an open line request for an order on order holder 40 requests inventory item 42 located in inventory storage 48 .

Management module 15 may instruct mobile drive unit 20 to ship order holder 40 to inventory station 56 at step 624 so that any items that should be placed in container 60 of order holder 40 may be received at step 628 . For example, the management module 15 may determine the order lines that are populated on the stock-only order holder 40 and/or the mixed order holder 40 at the stock station 56 . Step 624 may occur before, after, and/or alternately before mobile drive unit 20 transports order holder 40 to inventory holder 50 .

At step 626 , while the order holder 40 is located at the inventory station 56 , the management module 15 may locate the inventory item 42 stored in the inventory holder 30 and/or the pallet holder 34 in the inventory store 48 . Based on the stored locations of inventory items 42, management module 15 may instruct one or more mobile drive units 20 to move to the locations of inventory holders 30 and/or pallet holders 34 that store those inventory items 42 within inventory storage 48. . At step 626 , mobile drive unit 20 may transport the inventory holder 30 and/or pallet holder 34 storing the requested inventory item 42 to inventory station 56 .

In step 628 , the inventory items 42 stored by the inventory holder 30 and shipped to the inventory station 56 may be received by the appropriate container 60 of the order holder 40 . After container 60 receives requested inventory item 42 from inventory holder 30 , management module 15 determines whether the order is complete at step 630 . If there are outstanding orders, the method 600 may return to step 610 where the management module 15 determines whether to fill additional lines of orders in the inventory racks 50 and/or order holders 40 at the inventory stations 56 . If an additional line is determined to fill an order at inventory station 56 , order holders 40 may remain at inventory station 56 and additional inventory holders 30 containing additional requested inventory items 42 may be shipped to inventory station 56 . If an additional line is determined to fill the order at inventory holder 50 , the method may continue to step 614 where order holder 40 may be shipped to inventory holder 50 . Method 600 continues until the order in order holder 40 is completed at step 620 or 630 . Once complete, order holder 40 is transported by mobile drive unit 20 to inventory station 56 and/or shipping station 58 for preparation and/or shipment to an end user and/or shipping destination.

FIG. 7 is a flowchart illustrating an example method 700 of facilitating fulfillment of an order at an inventory holder. Method 700 begins at step 702 where selection of an inventory holder 30 to be placed at an inventory holder 50 is initiated. Method 700 is an example implementation of step 602 of method 600 in FIG. 6 .

The method of selecting inventory 30 may be based on speed and/or order line fulfillment. If an inventory holder 30 is selected based solely on the velocity at step 704 , the method proceeds to step 706 where the velocity and/or volume of available inventory items 42 in the inventory system 10 is calculated. The rate at which inventory items 42 are available may be calculated by any suitable metric including historical ordering trends and/or current outstanding orders and/or expected orders that are forecast to occur within inventory system 10 . As discussed above, velocity may represent a relative rate at which the order includes each inventory item and/or may include the volume under which the ordered inventory item 42 is placed. Volume may refer to the amount of inventory item 42 ordered for a particular order, and may additionally or alternatively represent a physical volume based on the actual size of inventory item 42 . Accordingly, management module 15 may determine to locate inventory items 42 at inventory holders 50 based on the actual amount of space these inventory items 42 occupy. For example, large and/or bulky items may be selected for placement at inventory holder 50 . In some embodiments, management module 15 may calculate the total system activity within inventory system 10 generated by a particular SKU and/or unique inventory item 42 . The inventory holder 30 and/or the pallet holder 34 may be selected based on minimizing overall system activity.

At step 708 , the inventory holder 30 and/or the pallet holder 42 storing the inventory item 42 having the highest velocity is selected for placement at the inventory holder 50 . In an example embodiment, the inventory holder 50 may have up to fifty inventory items 42 located along the inventory holder 50 in ten inventory holders 30 (each located in one of ten defined areas), where each inventory holder 30 Five of up to fifty inventory items 42 are stored. If one of the defined areas 80 becomes available because, for example, one of the stock holders 30 is about to run out of inventory items 42 and/or one of the defined areas 80 has not yet been filled, the management module 15 may then select an average storage Another inventory holder 30 for five of the highest velocity inventory items 42 is positioned at this defined area 80 . It should be noted that while specific quantities are provided by way of example, any suitable quantity and/or combination of inventory holders 30 and/or pallet holders 34 may be positioned at inventory holders 50 and that these inventory holders 30 and/or pallet holders 34 may store any suitable amount and/or combination of inventory items 42 at various speeds.

If at step 704, the inventory holder 30 and/or pallet holder 34 is not based on velocity alone but is also based on the expected order line, then at step 710 the method proceeds to step 712 where each inventory holder is calculated Excellent line order fulfilled by retainer 30. For example, management module 15 may determine each inventory item 42 stored by each inventory holder 30 within inventory system 10 . Management module 15 may determine the quantity of an order line that would be filled if that particular inventory holder was placed at inventory holder 50 . Each keeper may be assigned a score based on the total amount of excellent line orders fulfilled. Step 710 may additionally or alternatively base the selection of inventory holders 30 and/or pallet holders 34 on total order fulfillment based on outstanding order expectations in inventory system 10 . For example, a preference weight may be given to an inventory holder 30 that includes a combination of one or more inventory items 42 that fulfill more actual orders than another inventory holder 30 .

At step 714 , the management module 15 may determine a desired quantity of order lines that each inventory holder 30 and/or pallet holder 34 fulfills. For example, if inventory system 10 expects to receive a large order for a particular inventory item 42 , this may be taken into account when scoring each inventory holder 30 . Based on the totals determined in steps 712 and 714 , an order line total filled by each stock holder 30 may be calculated at step 716 and/or a score assigned to each stock holder 30 may be aggregated. Step 714 may additionally or alternatively base the selection of inventory holders 30 and/or pallet holders 34 on the desired total order fulfillment of the desired order in inventory system 10 . For example, a preference weight may be given to an inventory holder 30 that includes a combination of one or more inventory items 42 that are expected to be predicted to fulfill more actual orders in the future than another inventory holder 30 .

Based on each stock holder's total, the stock holder 30 or pallet holder 34 with the highest total line order fulfillment and/or best score may be determined at step 718 . If the two highest inventory holders match, the method at step 720 may proceed to step 706 where the relative velocity of the available inventory items 42 in each inventory holder 30 is calculated and the inventory item with the highest velocity may be selected at step 708 42 of an inventory holder 30 or pallet holder 34. If not, the method may proceed to step 722 and the stock holder with the highest total order fulfillment and/or best score may be selected. Step 718 may additionally or alternatively base the selection of inventory holders 30 and/or pallet holders 34 on the total amount of outstanding orders expected to be fulfilled and forecast orders expected to be fulfilled. Additionally, it should also be noted that method 700 is discussed above as selecting a single inventory holder 30 for placement at a single inventory holder 50, but a similar method could be used to select multiple inventory holders 30 and/or pallet holders 34 at one or Substantially all or most of the plurality of inventory holders 50 define the area 80 . For example, method 700 may be used to select up to thirty inventory holders 30 corresponding to thirty defined areas 80 at inventory holders 50 .

8 is a flowchart illustrating an example method 800 of facilitating fulfillment of an order at an inventory holder. Method 800 begins at step 802, where the selection of placement order holders 40 is initiated. Method 800 is an example implementation of step 612 of method 600 .

At step 802 , the management module 15 begins to place the order holder 40 . For example, management module 15 may initiate placement of rack-only order holders 40 , hybrid order holders 40 , and/or station-only order holders 40 . At step 806 , the management module 15 may select the first order for inclusion in the order holder 40 . For example, outstanding orders for inventory items 42 may be examined to determine how many lines request inventory items 42 located at inventory holders 50 and/or how many lines request inventory items 42 located in inventory storage 48 per order. Outstanding orders may additionally or alternatively be examined to determine how many total inventory items 42 are located at inventory holder 50 on each order and/or how many total inventory items 42 are located in inventory storage 48 on each order. Each order may be assigned a score based on the total inventory items 42 on each order and/or the bus is located at the inventory holder 50 . Based on the type of order holders 40 to be placed and the score for each order, the management module 15 may select an appropriate first order to start placing the order holders 40 . For example, for an inventory-only order holder 40 , the management module 15 may select the first order with the best score, the most line of inventory items 42 , and/or the most total inventory items 42 located at the inventory holder 50 . If an inventory-only order holder 40 is deployed, management module 15 may optionally request an appropriate order for inventory items 42 located at inventory storage 48 . If deployment of hybrid order holders 40 begins, management module 15 may optionally request appropriate orders for inventory items 42 located at inventory holders 50 and/or located in inventory storage 48 . It should be noted that an order may include multiple inventory items 42 located at inventory holder 50 , especially because, as explained above, management module 15 may select the inventory holder 30 and/or pallet holder 34 calculated to fulfill the most orders. Thus, it is possible that a given order has all of its inventory items 42 already located at the inventory holder 50 .

At step 808 , the container 60 associated with each selected order may be placed on the order holder 40 . The management module may, for example, provide instructions to the operator of the guidance station 54 as to which containers 60 to add to the order holder 40 and/or how to associate a given order with a particular container 60 . The management module 15 may additionally or alternatively instruct the operator where to place the container 60 on the order holder 40 . For example, a particular order holder 40 may have space for a particular size and/or type of container 60 on one shelf, and may have space available for different quantities of different types of containers 60 . The management module 15 may take into account the size and/or type of each container 60 when placing the order on the order holder 40 . If the order holder 40 has associated containers 60 therein with other orders, the management module 15 may determine how to place the other containers 60 relative to those containers 60 . Additionally or alternatively, the management module 15 may consider the space occupied by the container 60 selected for the order when determining whether to place the order on the order holder 40 at step 806 and/or step 812 .

At step 810 , management module 15 may determine whether additional space is available for additional order containers 60 in order holder 40 . If there is additional space available, then at step 812 the management module 812 can determine that one or more other orders are included in the order holder 40 . For example, management module 15 may add orders for inventory items 42 at inventory holders 50 and/or may add orders for inventory items 42 at other locations within inventory system 10 .

At step 812 , management module 15 may additionally or alternatively determine other orders that also include inventory items at inventory holder 50 . Based on orders that include inventory items 42 that are also located at inventory holders 50 , management module 15 may select orders for placement on order holders 40 . For example, management module 15 may select two or more orders to group into order holder 40 . The two or more orders may include the first order selected at step 806 and one or more other orders. Orders other than the first order may be selected based on the inventory items 42 requested by the selected first order. For example, orders may be grouped into order holders 40 based on having the same and/or similar inventory items 42 as the first selected order. Orders selected for placement on order holder 40 may be based, for example, on the amount of travel calculated by mobile drive unit 20 to travel to inventory holder 50 and/or other locations in inventory system 10 . If not grouped into calculated travel volumes resulting from selecting two or more orders, management module 15 may determine the calculated hedge by comparing the travel volumes required to fulfill the orders in other ways. The management module 15 may select orders to group that reduce and/or minimize the amount of the overall trip. Management module 15 may also select to group orders that reduce and/or minimize the amount of overall task assignments generated by management module 15 . For example, management module 15 may determine to reduce the amount of tasks assigned to mobile drive unit 20 to fill the order.

As discussed above, management module 15 may select two or more from available orders based on determining that the order only includes inventory items located in one or more inventory holders 30 and/or pallet holders 34 housed at inventory holders 50. multiple orders. For example, management module 15 may determine to place inventory-only rack order holders 40 , hybrid order holders 40 , and/or inventory-only order holders 40 . For various reasons, management module 15 may determine to add to order holder 40 an order including inventory items 42 located elsewhere within inventory system 10 , such as inventory storage 48 , to form hybrid order holder 40 . This determination can be made based on any of the factors discussed above. The determination may be based on the workload at inventory holder 50 .

As noted above, management module 15 may also consider the location of inventory items 42 on inventory holders 50 when determining the placement of orders on a given order holder 40 . For example, management module 15 may determine to select an order requesting inventory items 42 in different inventory holders 30 located at inventory holders 50 . Specifically, management module 15 may be based on determining a first order for an inventory item 42 stored by an inventory holder 30 located at a defined area 80 of inventory holder 50 and determining a second order for an inventory item 42 stored by inventory holder 50 located at a defined area 80 of inventory holder 50. A group order is determined for another inventory item 42 stored in another inventory holder 30 in another defined area 80 at the location.

Once the order holder 40 is full and/or has no additional space available at step 810, the method ends. It should be noted that while method 800 is illustrated as adding orders to order holder 40 one at a time, management module 15 may predetermine all orders and/or containers 60 to be added to a particular order holder 40 .

Modifications, additions, or omissions may be made to the methods 600, 700, and 800 illustrated in the flowcharts of FIGS. 6-8, respectively. For example, management module 15 can assign multiple tasks at once and/or in parallel. Thus, the management module 15 can also process many orders in parallel and/or sequentially. Additionally, management module 15 may be capable of using inventory holder 50 to fulfill orders for any number and type of inventory facility. Management module 15 may be capable of fulfilling orders with multiple inventory holders 50 according to the principles discussed above with reference to FIG. 4 . Orders corresponding to various of those facilities may be processed sequentially and/or simultaneously by management module 15 using various inventory stations 56 and/or inventory holders 50 . Furthermore, the steps of FIGS. 6-8 may be performed in parallel or in any suitable order. Furthermore, embodiments described with reference to this disclosure are contemplated to be fully incorporated and applicable to appropriate embodiments described herein.

FIG. 9 illustrates an example computer system 900 that may be used with one or more portions of the systems and methods disclosed herein. In particular embodiments, one or more computer systems 900 perform one or more steps of one or more methods described or illustrated herein. In particular embodiments, one or more computer systems 900 provide the functionality described or illustrated herein, such as, for example, any suitable components of system 10 (such as management module 15, mobile drive unit 20, and/or inventory holder 50) . In particular embodiments, software running on one or more computer systems 900 performs one or more steps of one or more methods described or illustrated herein, or provides functionality described or illustrated herein. Particular embodiments include one or more portions of one or more computer systems 900 .

This disclosure contemplates any suitable number of computer systems 900 . This disclosure contemplates computer system 900 in any suitable physical form. By way of example and not limitation, computer system 900 may be an embedded computer system, a system on a chip (SOC), a single board computer system (SBC) such as, for example, a computer on module (COM) or a system on module (SOM)), a desktop computer system, Laptop or notebook computer systems, interactive kiosks, mainframes, networks of computer systems, mobile phones, personal digital assistants (PDAs), servers, tablet computer systems, or a combination of two or more of these devices. The computer system 900 may suitably comprise one or more computer systems 900; be singular or distributed; span multiple locations; span multiple machines; span multiple data centers; or reside in the cloud, which may comprise one or One or more cloud components in multiple networks. One or more computer systems 900 may suitably perform (without substantial spatial or temporal limitation) one or more steps of one or more methods described or illustrated herein. By way of example and not limitation, one or more computer systems 900 may perform one or more steps of one or more methods described or illustrated herein in real-time or in batch processing mode. One or more computer systems 900 may perform at different times or at different locations, as appropriate, one or more steps of one or more methods described or illustrated herein.

In a particular embodiment, computer system 900 includes processor 902 , memory 904 , storage 906 , input/output (I/O) interface 908 , communication interface 910 , and bus 912 . Although this disclosure describes and illustrates a particular computer system having a particular number of particular components in a particular arrangement, this disclosure contemplates any suitable computer system having any suitable number of any suitable components in any suitable arrangement.

In particular embodiments, processor 902 includes hardware for executing instructions, such as those making up a computer program. By way of example and not limitation, to execute instructions, processor 902 may retrieve (or fetch) instructions from internal registers, internal cache, memory 904, or storage 906; decode and execute the instructions; and then write one or more results to into internal registers, internal cache, internal memory 904, or storage 906. In particular embodiments, processor 902 may include one or more internal caches for data, instructions, or addresses. Although this disclosure describes and illustrates a particular processor, this disclosure contemplates any suitable processor.

In particular embodiments, memory 904 includes main memory for storing instructions for execution by processor 902 or data for manipulation by processor 902 . In some embodiments, memory 904 may be memory included in any of the system 10 components discussed above, such as management module 15 , mobile drive unit 20 , and/or inventory holder 50 . Memory 904 may store any suitable information for components of system 10 , such as a number of orders and/or information associated with a number of orders received by management module 15 . By way of example and not limitation, computer system 900 may load instructions into memory 904 from memory 906 or from another source, such as, for example, another computer system 900 . Processor 902 may then load the instructions from memory 904 into internal registers or internal cache. For example, process 902 may obtain information associated with a plurality of orders stored in memory 904 . To execute the instructions, processor 902 may retrieve the instructions from an internal register or internal cache and decode the instructions. During or after execution of the instructions, processor 902 may write one or more results (which may be intermediate or final results) to an internal register or internal cache. Processor 902 may then write one or more of those results to memory 904 . In particular embodiments, processor 902 executes only instructions in one or more internal registers or internal caches or in memory 904 (rather than memory 906 or elsewhere), and operates only on one or more internal registers or internal caches or Data in memory 904 (rather than storage 906 or elsewhere). One or more memory buses (which may each include an address bus and a data bus) may couple processor 02 to memory 904 . Bus 912 may include one or more memory buses, as described below. In particular embodiments, one or more memory management units (MMUs) reside between processor 902 and memory 904 and facilitate access to memory 904 as requested by processor 902 . Although this disclosure describes and illustrates particular memory, this disclosure contemplates any suitable memory.

In particular embodiments, memory 906 includes mass storage for data or instructions. In certain embodiments, memory 906 may be included in any suitable component of system 10 , including management module 15 , mobile drive unit 20 , and/or inventory holder 50 . Memory 906 may store any suitable information for components of system 10 , such as a number of orders and/or information associated with a number of orders received by management module 15 . Storage 906 may comprise removable or non-removable (eg, fixed) media, as appropriate. Memory 906 may be internal or external to computer system 900 as appropriate. In a particular embodiment, memory 906 is non-volatile solid-state memory. Memory 906 may include one or more memories 706 as appropriate. Although this disclosure describes and illustrates particular memory, this disclosure contemplates any suitable memory.

In particular embodiments, I/O interface 908 includes hardware, software, or both, that provides one or more interfaces for communication between computer system 900 and one or more I/O devices. Computer system 900 may include one or more of these I/O devices as appropriate. One or more of these I/O devices may enable communication between a person and computer system 900 . By way of example and not limitation, an I/O device may include a keyboard, keypad, microphone, monitor, mouse, printer, scanner, speaker, still camera, light pen, tablet, touch screen, trackball, video camera, another suitable I/O devices, or a combination of two or more of these devices. An I/O device may include one or more sensors. This disclosure contemplates any suitable I/O device and any suitable I/O interface 908 for such a device. I/O interface 908 may suitably include one or more device or software drivers that enable processor 902 to drive one or more of these I/O devices. I/O interfaces 908 may include one or more I/O interfaces 908 as appropriate. Although this disclosure describes and illustrates particular I/O interfaces, this disclosure contemplates any suitable I/O interfaces.

In particular embodiments, communication interface 910 includes hardware, software, or both, that provides for communication between computer system 900 and one or more other computer systems 900 or one or more networks (such as, for example, packet-based communications). By way of example and not limitation, communication interface 910 may include: a network interface controller (NIC) or network adapter for communicating with Ethernet or other wire-based networks; or a wireless NIC (WNIC) or wireless adapter for for communicating with wireless networks, such as Wi-Fi networks. This disclosure contemplates any suitable network and any suitable communication interface 910 for the network. Although this disclosure describes and illustrates a particular communication interface, this disclosure contemplates any suitable communication interface.

In particular embodiments, bus 912 includes hardware, software, or both, and couples the components of computer system 900 to each other. Although this disclosure describes and illustrates a particular bus, this disclosure contemplates any suitable bus or interconnect.

Herein, reference to a computer-readable storage medium encompasses one or more non-transitory, tangible computer-readable storage medium processing structures. By way of example and not limitation, computer-readable storage media may suitably include semiconductor-based or other integrated circuit (IC) (such as, for example, field-programmable gate array (FPGA) or application-specific IC (ASIC), hard disk, HDD, hybrid hard drive ( HHD), optical disk, optical disk drive (ODD), magneto-optical disk, magneto-optical drive, floppy disk, floppy disk drive (FDD), magnetic tape, holographic storage media, solid-state drive (SSD) RAM drive, secure digital card, secure digital drive, or another An appropriate computer-readable storage medium, or a combination of two or more of these devices. The computer-readable non-transitory storage medium can be volatile, non-volatile, or both volatile and non-volatile combination.

This disclosure contemplates one or more computer-readable storage media implementing any suitable memory. In particular embodiments, computer-readable storage media suitably implement one or more portions of processor 902 (such as, for example, one or more internal registers or caches), one or more portions of memory 904, one or more portions of memory 906, or multiple parts, or a combination of these. In particular embodiments, the computer readable storage medium implements RAM or ROM. In particular embodiments, a computer readable storage medium implements volatile or persistent memory. In certain embodiments, one or more computer-readable storage media include software. As used herein, reference to software may encompass one or more applications, byte code, one or more computer programs, one or more executable files, one or more instructions, logic, machine code, one or more scripts or source code, and vice versa where appropriate. In certain embodiments, software includes one or more application programming interfaces (APIs). This disclosure contemplates any suitable software written or otherwise expressed in any suitable programming language or combination of programming languages. In certain embodiments, software is expressed as source code or object code.

Herein, "or" is inclusive and not exclusive, unless expressly indicated otherwise or indicated otherwise by context. Thus, herein, "A or B" means "A, B, or both" unless expressly indicated otherwise or indicated otherwise by context. Furthermore, "and" is both several and several, unless expressly indicated otherwise or indicated otherwise by context. Thus, herein, "A and B" means "A and B, jointly or severally," unless expressly indicated otherwise or indicated otherwise by context.

This disclosure encompasses all changes, substitutions, variations, substitutions, and modifications to the example embodiments herein that would occur to one of ordinary skill in the art. Similarly, the appended claims suitably encompass all modifications, substitutions, variations, changes, and modifications to the example embodiments herein that would occur to those of ordinary skill in the art. Furthermore, reference in the appended claims to a device or system or a component of a device or system that is adapted, arranged, capable, configured, activated, operable or operative to perform a specified function encompasses all said device, system, component, regardless of whether said device, system, component or said specific function is activated, opened or unlocked, as long as said device, system or component is so adapted, arranged, able, configured, Initiate, be operable, or operate.

Any of the steps, operations or processes described herein may be performed or carried out using one or more software or software modules alone or in combination with other means. In one embodiment, a software module is implemented using a computer program product comprising a computer-readable medium containing a computer-readable medium executable by a computer processor for performing any or all of the steps, operations, or processes described. code.

Embodiments of the invention may also relate to apparatus for performing the operations herein. This apparatus may be specially constructed for the required purposes, and/or it may comprise a general purpose computing device selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a tangible computer readable storage medium or any type of medium for storing electronic instructions and coupled to a computer system bus. Furthermore, any computing system mentioned in the specification may include a single processor or may be an architecture employing multiple processors designed for increased computing power.

While a particular embodiment of an inventory system 10 is illustrated, it should be understood that the teachings of the present disclosure are applicable to any type and number of inventory systems. For example, inventory system 10 may represent a merchandise returns facility. In such an embodiment, an inventory item may represent merchandise returned by a customer. These items may be stored in inventory holders 130 as they are received at the facility from individual customers. At the appropriate time, a number of units may be removed from a particular inventory holder 30 and the inventory holder 40 shipped at the inventory holder 50 . For example, certain inventory items may be associated with product recalls causing these inventory items to be returned in high volume. As another example, system 10 may represent a production facility, and inventory items may represent individual components of a production kit. Accordingly, individual items of a production kit may be stored in inventory holder 30 . Orders for production products can be assembled from individual items from the inventory holder 50 . The final product can be shipped by mobile drive unit 20 using the order holder and can be shipped to the appropriate destination. Thus, while several example embodiments are described in this disclosure, inventory system 10 may generally represent any suitable facility or system for storing or handling inventory items, and inventory items may represent devices suitable for storage, retrieval, and/or storage in a particular inventory system 10. or any type of object handled.

In some embodiments, management module 15 may generate task assignments as part of the overall management and maintenance of inventory system 10 independently of these inventory requests. For example, management module 15 may respond to the occurrence of a particular event (e.g., in response to mobile drive unit 20 requesting space to dock), according to a predetermined schedule (e.g., as part of, e.g., a daily start-up procedure), or at any appropriate time based on inventory system 10's Construction and feature generation task assignment. Furthermore, while management module 15 may be configured to manage various aspects of the operation of components of inventory system 10, in certain embodiments, the components themselves may also be responsible for making decisions about certain aspects of their operation, thereby reducing processing on management module 15. load. In particular, individual components can be configured to independently respond to specific localized circumstances in a manner that allows these components to improve their efficiency without reducing the overall efficiency of inventory system 10 . As an example, management module 15 may rely on independent decisions of mobile drive units 20 to prevent collisions. Furthermore, while the above description focuses on one or more implementations in which mobile drive unit 20 requests a path from management module 15 , in alternative implementations mobile drive unit 20 may generate its own path. Additionally, while the above discussion describes moving order holders 40 along a side of inventory holder 50 , the teachings of the present disclosure are also applicable to configurations in which transport equipment is positioned along a side of inventory holder 50 . Containers 60 may be moved along the conveyor and stopped at various locations to receive inventory items 42 in a manner similar to that described above with reference to order holders 40 . Additionally, in some embodiments, mobile drive unit 20 may include a transport device.

Various embodiments of the disclosure may be described in terms of the following terms:

1. A method comprising: designating, by a management module, a plurality of inventory holders to be disposed in a plurality of defined areas along a first side of an inventory holder; instructing, by the management module, one or more first mobile drive units to deliver the plurality of inventory holders to the plurality of defined areas, wherein the plurality of inventory holders remain stationary at the plurality of defined areas while fulfilling a plurality of orders; receiving orders for a plurality of inventory items; by the the management module determines that an inventory item requested by the order is stored in an inventory holder disposed at a defined area at the inventory holder, wherein the inventory holder is one of the plurality of inventory holders; and instructing, by the management module, a second mobile drive unit to deliver an order holder to a second side of the inventory holder, wherein the second mobile drive unit moves along the second side such that the order holder is operable to The inventory item is received at a location along the second side of the inventory holder opposite the defined area of the inventory holder.

2. The method of clause 1, further comprising: determining that the order requests additional inventory items; instructing the second mobile drive unit to ship the order holder to a stocking station; and instructing the first mobile drive unit One of transports an inventory holder storing the additional inventory item from an inventory storage location to the inventory station.

3. The method of clause 1, wherein the inventory holder is a first inventory holder and the method further comprises: determining that the order requests additional inventory items; instructing the second mobile drive unit to ship the order holder to a second inventory holder; and fulfilling the order at the second inventory holder with the additional inventory item.

4. The method of clause 1, further comprising: activating a signal at the inventory holder indicating that an order holder moving along the second side will stop at the location opposite the defined area; and instructing an operator of the inventory holder to move to the defined area based at least in part on the signal.

5. The method of clause 1, wherein the defined area comprises a first defined area, the inventory holder comprises a first inventory holder, and the method further comprises: based at least in part on a first triggering event, indicating that the one of the first mobile drive units removes the first inventory holder from the first defined area and transports the first inventory holder to a drift position associated with the inventory holder; indicating a third movement a drive unit transporting a second inventory holder to said first defined area; and based at least in part on a second trigger event, instructing one of said first mobile drive units to transport said first inventory holder from said drift location to a second defined area at the stock holder.

6. The method of clause 1, further comprising: determining a rate at which each of a plurality of inventory items is ordered within the inventory system; comparing the rates of each of the plurality of inventory items; at least in part Based on the comparison, selecting an amount of inventory items above a predetermined rate; and wherein designating the plurality of inventory holders to be located in the plurality of defined areas is based at least in part on determining that the amount of inventory items is stored in the plurality of in the stock holder.

7. A system comprising:

an inventory holder including a first side and a second side, the first side including a plurality of defined areas where a plurality of inventory holders are designated for placement, the inventory holder operable to receiving inventory items from at least one of the inventory holders at at least one of a plurality of defined areas; and a mobile drive unit operable to transport order holders along the second side of the inventory holder, wherein the The order holder is operable to receive inventory items from the inventory holder at a location along the second side of the inventory holder.

8. The system of clause 7, wherein the location along the second side of the inventory holder is opposite a defined area on the first side having an inventory holder storing the inventory item .

9. The system of clause 7, wherein the mobile drive unit comprises a first mobile drive unit and the system further comprises a second mobile drive unit operable to transport one or One or more of a plurality of defined areas at the inventory holder.

10. The system of clause 7, wherein the plurality of inventory holders are designated for the defined area based at least in part on a product velocity of one or more inventory items stored in the plurality of inventory holders.

11. The system of clause 7, wherein the plurality of stock holders remain seated at a defined area while filling a plurality of orders.

12. The system of clause 7, wherein the order holder is operable to hold a plurality of containers, wherein at least some of the containers are compatible with inventory items requested to be stored in one of the plurality of stock holders associated with one or more orders for .

13. The system of clause 7, the mobile drive unit further operable to: replace a first inventory holder of the plurality of inventory holders with a second inventory holder at one of the defined areas, wherein The first inventory holder is replaced based at least in part on metrics associated with the first inventory holder.

14. The system of clause 7, wherein one or more of the defined areas are designated for storing waste holders and the mobile drive unit is operable to transport the waste holders.

15. The system of clause 7, wherein the first mobile drive unit is operable to move one of the plurality of inventory holders to a drift position associated with the inventory holder.

16. The system of clause 7, the inventory holder further comprising an interface operable to instruct an operator of the inventory holder to remove the inventory item from one of the plurality of inventory holders and The inventory item is placed in a container stored in the order holder, the container being associated with the order.

17. The system of clause 7, the inventory holder further comprising a first operator zone and a second operator zone, wherein the first operator zone designations apply to the first operator to place the inventory item into the in said order holders at a first subset of said defined area, and said second operator zone is designated for a second operator to place inventory items into all said order holders at a second subset of said defined area in the order holder described above.

18. The system of clause 7, the inventory holder further comprising one or more of a flat surface, a raised surface, and a virtual area of the booth.

19. A system comprising: an inventory holder; an order holder; and a mobile drive unit operable to:

transporting the inventory holder to a defined area of a first side of an inventory holder; delivering the order holder to the inventory holder; moving the order holder along a second side of the inventory holder; A location on a second side opposite the defined area, wherein the order holder is operable to receive inventory items from the stock holder at the defined area.

20. The system of clause 19, wherein the inventory holder is a first inventory holder and the mobile drive unit is further operable to replace the first inventory holder with a second inventory holder and the system further includes a management module based at least in part on comparing a first metric associated with the first inventory keeper with a second metric associated with the second inventory keeper indicating The mobile drive unit replaces the first inventory holder with the second inventory holder.

21. The system of clause 20, wherein the first metric includes one or more of: the amount of inventory items stored in the first inventory holder; The velocity of inventory items in the inventory keeper.

22. The system of clause 20, wherein the first metric comprises a first expected demand, the second metric comprises a second expected demand, and the management module is further operable to determine the predicted demand based at least in part at a particular time. The first inventory holder is scheduled to be replaced by the second inventory holder at the specified time if the second expected demand exceeds the first expected demand.

23. The system of clause 20, wherein the mobile drive unit is operable to transport the inventory holder by: moving under the inventory holder; raising a docking head toward a surface of the inventory holder ; raising the inventory holder using the docking head; moving while raising the inventory holder.

24. The system of clause 19, further comprising a management module operable to: determine that the inventory holder should be rotated; and instruct the mobile drive based at least in part on the determination that the inventory holder should be rotated A unit does the following: move the inventory holder away from the defined area; rotate the inventory holder; and move the inventory holder back to the defined area.

A1. A method for fulfilling an order at an inventory holder, the method comprising: receiving, by a management module, a plurality of orders, a first order comprising a request for one or more inventory items; an order to identify an inventory item stored by an inventory holder mounted at an inventory holder; based at least in part on a request by the management module to determine that the first order and the second order include the inventory item while grouping said first order of said plurality of orders with said second order; disposing on an order holder at a guiding station a first container associated with said first order and a first container associated with said second order an associated second container, wherein the first container and the second container are operable to receive the inventory item; and instructing, by the management module, a mobile drive unit to transport the order holder from the induction station to the inventory holder, wherein the order holder receives the inventory item from the inventory holder at a location opposite the inventory holder.

A2. The method of clause A1, further comprising: determining whether the first order and the second order are fulfilled at the inventory holder; if the first order and the second order are fulfilled at the completion at the inventory holder, instruct the mobile drive unit to transport the order holder to a shipping station; and if the first order and the second order are not completed at the inventory holder, instruct the mobile A drive unit transports the order holders to a stocking station.

A3. The method of clause A1, further comprising: determining whether the order holder has space available for an additional container after adding the first container and the second container; and if the order holder With space available, add additional containers to the order holder.

A4. The method of clause A1, wherein the inventory item comprises a first inventory item, the inventory holder comprises a first inventory holder, and the method further comprises: verifying whether any of the plurality of orders includes requesting an order for a second inventory item of the plurality of inventory items, the second inventory item being stored by a second inventory holder positioned at the inventory holder; and wherein based at least in part on including the first inventory item and grouping the first order and the second order with one or more of the first order and the second order for the second inventory item.

A5. The method of clause A1, further comprising: assigning a first score to the first order and a second score to the second order, the scores being based at least in part on: one or more of the order requests received and the amount of inventory items on the order located at the inventory holder; and determining to group the order holders based at least in part on the first score and the second score The first order and the second order.

A6. A management module comprising: a memory operable to store information associated with a plurality of orders for a plurality of inventory items; a processor communicatively coupled to the memory and operable to: obtain information associated with the plurality of inventory items information associated with the plurality of orders; select two or more units to ship the order holder to an inventory rack; wherein the two or more orders receive the Inventory items for two or more order requests.

A7. The management module of claim A6, the processor further operable to: calculate the amount of travel required of the mobile drive unit to the inventory holder to fill the plurality of orders; and based at least in part on The calculated travel amount, determining that selecting two or more orders and transporting the order holder to the inventory holder by the mobile drive unit will reduce the travel amount.

A8. The management module of clause A6, the process being further operable to request only those located in one or more inventory holders housed at the inventory holder based at least in part on determining that the two or more orders request only Selecting the two or more orders from the plurality of orders to add to the order holder.

A9. The management module of clause A6, the processor further operable to: provide a first instruction to assemble an order with an order comprising a first inventory item stored in an inventory holder housed at the inventory holder holder; providing first instructions to assemble an order with an order comprising a first inventory item stored in an inventory holder mounted at the inventory holder and a second inventory item stored at a location other than the inventory holder a holder; and providing third instructions to assemble the order holder with an order comprising a second inventory item stored at a location other than the inventory holder.

A10. The management module of clause A9, the processor further operable to: obtain information indicative of a rate at which falling inventory items are added to one or more order holders moving along a side of the inventory holder and, based at least in part on the rate, determining a selected instruction to provide the first instruction, the second instruction, and the third instruction.

A11. The management module of clause A6, the processor further operable to: determine whether the workload at the inventory holder is greater than a maximum workload; and if the workload is greater than the maximum, then determine whether Orders are fulfilled at different stocking stations than the stocking brackets described above.

A12. The management module of clause A6, wherein the two or more orders comprise a first order and a second order, and the processor is further operable to: utilize the order holder based at least in part on the first order and the second order selected for fulfillment: determining that the first order is for first inventory stored by a first inventory holder positioned at a first defined area at the inventory holder items; and determining that the second order is for a second inventory item stored by a second inventory holder positioned at a second defined area at the inventory holder.

A13. The management module of clause A6, the processor further operable to: instruct an operator of the inventory holder where it expects the order holder to receive the order holder as the order moves along the inventory holder. A specific location for the described inventory item.

A14. A non-transitory computer-readable medium comprising logic operable when executed by a processor to: instruct a first mobile drive unit to transport an inventory holder to an inventory holder, the instructions being responsive to the velocity of one or more inventory items stored in the holder; and instructing a second mobile drive unit to transport an order holder to the inventory rack, the instruction being responsive to an order comprising the one or more inventory items, wherein the The second mobile drive unit moves the order holder along the inventory holder to receive one or more of the inventory items.

A15. The computer readable medium of clause A14, the logic further operable to activate an indicator on the inventory holder that provides an indicator under which the order holder will stop to receive inventory items to An indication of the location in the two or more containers is given to an operator of the inventory holder.

A16. The computer-readable medium of clause A14, the logic further operable to ship the order holder to the inventory rack based at least in part on a job assignment of a plurality of operators at the inventory rack.

A17. The computer-readable medium of clause A14, the logic further operable to: instruct an operator to move along the inventory holder to a location under which the order holder will receive a first inventory item to the two or a position in a first container of a plurality of containers; and instructing the operator at the position to move the first inventory item from an inventory holder to the first container, the inventory holder comprising a plurality of stock items.

A18. The computer-readable medium of clause A14, the logic further operable to determine to ship the order holder to the inventory holder, wherein the inventory holder includes a plurality of workspaces and the determination is calculated to The workload is balanced across the multiple workspaces.

A19. The computer-readable medium of clause A18, wherein the workspace comprises defined areas at which inventory holders are located, and the logic is determined based at least in part on a velocity of inventory items stored by the inventory holders Shipping the stock holder to the defined area.

A20. The computer-readable medium of clause A14, wherein the order holder comprises a first order holder and the logic is further operable to:

As the first order moves along the inventory holder, it is determined whether a second order holder moving in the same direction blocks the order holder from the first order holder at which the order holder will receive the inventory item. the path between the destinations; and

If the second order holder blocks the path, then determining a second destination for the second order holder; and if the second destination is further along the inventory holder than the first destination , then activate the indicator at the first location and instruct the mobile drive unit to travel to the first location.

A21. The computer-readable medium of clause A14, the logic further operable to: in response to a first trigger event, instruct the mobile drive unit to ship the order holder to a drift associated with the inventory holder location; and in response to a second trigger event, instructing the mobile drive unit to transport the order holder from the drift location to the inventory holder.

A22. The computer-readable medium of clause A21, wherein the first trigger event includes a determination that the workload at the inventory holder exceeds a predetermined workload and the second trigger event includes a determination that the workload is below the predetermined workload. The scheduled workload.

B1. A method comprising: calculating, by a management module, a plurality of product velocities, product velocities associated with demand for inventory items available for placing an order within an inventory system; selecting, by said management module, placement on said inventory holder a fixed amount of inventory holders at a fixed amount corresponding to a plurality of defined areas along a first side of an inventory holder, wherein selecting where an inventory holder is placed in a defined area is based at least in part on the product velocity of the inventory item , the inventory item being stored by the inventory holder; instructing, by the management module, a mobile drive unit to deliver the selected inventory holder to the defined area; receiving an order for the inventory item, by the management module; and by The management module instructs the mobile drive unit to deliver an order holder associated with the order to a second side of the inventory holder, wherein the order holder is operable to move along the A second side receives the inventory item.

B2. The method of clause B1, wherein the inventory holder comprises a first inventory holder and the method further comprises: determining the first inventory holder on an order to be filled at the inventory holder and wherein selecting said first inventory holder is also based at least in part on determining that said first line amount on an order is greater than a second line amount of an order that a second inventory holder fills at said inventory holder .

B3. The method of clause B2, wherein selecting the first inventory holder is further based at least in part on determining that the first inventory holder will complete a greater amount at the inventory holder than the second inventory holder , the method further comprising: determining that the order will be fulfilled at the inventory rack if the plurality of inventory items requested by the order are all located in one or more inventory holders housed at the inventory rack .

B4. The method of clause B1, wherein the plurality of product velocities comprises one or more of: a first frequency at which the first inventory item appears on the plurality of orders for the inventory item; and A second frequency at which the second inventory item is expected to appear on the plurality of orders for the inventory item.

B5. The method of clause B4, wherein the inventory holder comprises a first inventory holder storing the first inventory item and the method further comprises: determining that the first frequency has changed; and based at least in part on A change in the first frequency determines the delivery of a second inventory holder to the defined area of the first inventory holder in place of the first inventory holder.

B6. A system comprising: an inventory holder comprising a defined area arranged to seat an inventory holder storing inventory items; a mobile drive unit operable to transport the order holder; and a management module, It is operable to: calculate a metric associated with demand for the inventory item; select from a plurality of inventory holders to store the inventory located at the defined area of the inventory holder based at least in part on the metric an inventory holder of items; receiving an order for said inventory item; instructing said mobile drive unit to deliver said order holder to said inventory holder, said order holder being operable to access said defined area from said inventory holder A holder receives the inventory item.

B7. The system of clause B6, wherein the metrics associated with demand include task assignments generated by the management module, and the management module is further operable to: based at least in part on receipt of the inventory item calculating the generated task assignment amount; and selecting the inventory holder to store the inventory item located at the defined area based at least in part on reducing the generated task assignment amount.

B8. The system of clause B6, the management module being further operable to: compare a product velocity for each of a plurality of inventory items available for placing an order; and based at least in part on the comparison, select a store with a high product velocity The quantity of inventory items in the stock holder; and

One or more mobile drive units are instructed to deliver the quantity of inventory holders to the inventory holder.

B9. The system of clause B6, wherein the order holder receives the inventory item at a location opposite a defined area of the inventory holder where the inventory item is stored.

B10. The system of clause B6, wherein: the mobile drive unit is further operable to ship the inventory holder; and the management module is further operable to instruct the mobile drive unit to ship the inventory holder to the limited area.

B11. The system of clause B10, wherein the inventory holder comprises a first inventory holder and the management module is further operable to instruct the mobile drive unit to replace the first inventory holder with a second inventory holder device.

B12. The system of clause B6, wherein the metric comprises product velocity determined based at least in part on at least one of past order information, known demand, and forecasted future order information.

B13. The system of clause B12, wherein the measure further comprises a product volume comprising a cubic volume of a quantity of inventory items requested by the plurality of orders.

B14. The system of clause B6, wherein the inventory holder includes two or more sides, each side capable of storing one or more inventory items and the management module is further operable to: the amount of inventory items on the holder is below a predetermined amount, the first side faces the inventory holder; and the mobile drive unit is instructed to rotate the inventory holder such that the second side of the inventory holder faces the Stock stand.

B15. A non-transitory computer-readable medium comprising logic operable when executed by a processor to: instruct a first mobile drive unit to transport an inventory holder to an inventory holder, the instructions being responsive to instructions issued by the inventory the velocity of one or more inventory items stored in the holder; and instructing a second mobile drive unit to transport an order holder to the inventory rack, the instruction being responsive to an order comprising the one or more inventory items, wherein the The second mobile drive unit moves the order holder along the inventory holder to receive one or more of the inventory items.

B16. The computer readable medium of claim B15, the logic further operable to designate the inventory holder for holding at one of a plurality of defined areas at an inventory holder while fulfilling a plurality of orders fixed.

B17. The computer-readable medium of claim B15, wherein: the speed comprises a first speed; the one or more inventory items comprise one or more first inventory items; the inventory holder comprises a first and the logic is further operable to: calculate the first velocity of the one or more first inventory items; and instruct the first mobile drive unit based at least in part on determining the one or more The first velocity of a first inventory item is higher than a second velocity of one or more second inventory items stored by a second inventory holder to transport the first inventory holder to the inventory holder.

B18. The computer-readable medium of claim B17, the logic further operable to: calculate the said first velocity of one or more first inventory items; and based at least in part on calculating said first velocity to be lower than a third velocity, instructing said first mobile drive unit to convey a third inventory holder to said inventory holder .

B19. The computer-readable medium of clause B15, wherein the velocity further comprises one or more of historical velocity, known demand, and expected demand.

B20. The computer-readable medium of clause B15, wherein the order holder comprises a first order holder and the logic is further operable to instruct a third mobile drive unit to transport a second order holder along the inventory rack , wherein the third mobile drive unit and the second mobile drive unit move in the same direction and along the inventory holder at substantially the same time.

B21. The computer-readable medium of clause B15, wherein the inventory holder comprises a first inventory holder, the order holder comprises a first order holder, and the logic is further operable to: instruct the The first mobile drive unit transports a second inventory holder storing the one or more inventory items to the inventory rack; and instructs a third mobile drive unit to transport the second order holder to the inventory rack, wherein at when said first holder receives one or more of said inventory items from said first inventory holder, said second order holder receives one of said inventory items from said second inventory holder or more, wherein the inventory items in the first inventory holder and in the second inventory holder are the same.

While the invention has been described using several embodiments, numerous changes, variations, alterations, transformations and modifications may be suggested to those skilled in the art and it is intended that the present invention cover such changes, Variations, changes, transformations and modifications. In addition, while the disclosure has been described with respect to various embodiments, it is fully contemplated that the teachings of the disclosure can be suitably combined in a single embodiment.

Claims (13)

CLAIMS 1. A system for fulfilling an order at an inventory stand comprising: An inventory holder including a location designated for processing inventory items according to a plurality of orders, the inventory holder having at least a first side and a second side parallel to the first side, the first side including a plurality of defined an area at which a first plurality of inventory holders is designated for placement, the inventory holder operable to remove from the first plurality of inventory holders at at least one of the plurality of defined areas at least one of receiving inventory items, wherein the first plurality of inventory holders remain fixed at the plurality of defined areas on a first side of the inventory holder while passing along a second side of the inventory holder moving the order holder laterally parallel to the first side of the inventory holder to fulfill multiple orders; and a first mobile drive unit comprising a self-powered robotic device; a management module operable to: Receive orders for multiple inventory items; determining that inventory items for the order request are stored in an inventory holder secured at a defined area of the inventory holder, wherein the inventory holder is one of the first plurality of inventory holders; transmitting wireless instructions to the first mobile drive unit based at least in part on receiving the order and determining that the inventory items requested for the order are stored in the inventory holder secured in the defined area; The first mobile drive unit is operable to, in response to receiving the wireless instruction from the management module, transport an order holder along at least a portion of a path on the second side of the inventory holder, wherein the order holder operable to receive the inventory item from the inventory holder at a first location along the second side of the inventory holder, the first mobile drive unit is also operable to receive the inventory item along the path from the the first position moves toward a second position on a second side of the inventory holder, and the inventory holder is configured to process the inventory item into one of the shipping containers stored by the order holder; and The management module is also operable to: detecting a change in product velocity associated with the stock holder at the defined area; Instructing a second mobile drive unit to transport the inventory holder away from the defined area based at least in part on detecting the change, wherein the second mobile drive unit is operable to travel along the first mobile drive unit along the The path on the second side of the inventory holder transports the inventory holder away from the defined area as it moves toward the second position. 2. The system of claim 1 , wherein the first plurality of inventory holders is designated for use at least in part based on a product velocity of one or more inventory items stored in the first plurality of inventory holders. the limited area. 3. The system of claim 1 , wherein at least a portion of the shipping containers stored by the order holder is the same as one of the inventory items requested to be stored in one of the first plurality of inventory holders. or multiple orders are associated. 4. The system of claim 1, the second mobile drive unit further operable to: Replacing the inventory holder of the first plurality of inventory holders at one of the defined areas with a second inventory holder from the first plurality of inventory holders based at least in part on a relationship with the inventory The keeper's associated metrics supersede the inventory keeper. 5. The system of claim 1 , the inventory holder further comprising an interface operable to instruct an operator of the inventory holder to remove the inventory item from the inventory holder and place the Inventory items are placed in shipping containers stored in the order holder, the shipping containers being associated with the order. 6. A method for fulfilling an order at an inventory stand, the method comprising: receiving, by a management module comprising logic encoded in the non-transitory medium and executed by the processor, a plurality of orders, a first order comprising a request for one or more inventory items; verifying, by the management module, the plurality of orders to identify inventory items associated with a particular product volume or a particular product velocity, the inventory items being housed in a plurality of inventory holders at a plurality of defined areas at an inventory rack an inventory keeper store, wherein the inventory holder includes a location designated for processing inventory products according to the plurality of orders, the inventory holder has at least a first side and a second side parallel to the first side, and said plurality of defined areas are located on said first side and are designated for inventory holders associated with one or more product volumes or one or more product velocities; assigning a first score to the first order and assigning a second score to the second order, the score being based at least in part on: (1) the amount of travel required to receive the one or more inventory items requested by the order; (2) and the quantity of inventory items on the order located at said inventory rack; determining to group the first order on the order holder based at least in part on the first score and the second score and that the first order and the second order include a request for the inventory item with the second order, and grouping the first order of the plurality of orders with the second order by the management module; Based at least in part on the grouping of the first order and the second order, arranging a first container associated with the first order and a container associated with the second order on an order holder at an induction station a second container, wherein the first container and the second container are operable to receive the inventory item; and In response to determining that the first container and the second container are disposed on the order holder, instructing, by the management module, a mobile drive unit comprising a self-powered robotic device, wherein the instructing is configured such that the a mobile drive unit transports the order holder from the guidance station to a second side of the inventory holder, wherein the order holder is along the second side of the inventory holder at a position opposite the inventory holder A location receives the inventory item from the inventory holder. 7. The method of claim 6, further comprising: determining whether the first order and the second order are fulfilled at the inventory holder; instructing the mobile drive unit to transport the order holder to a shipping station if the first order and the second order are fulfilled at the inventory holder; and If the first order and the second order are not fulfilled at the inventory holder, instructing the mobile drive unit to transport the order holder to an inventory station. 8. The method of claim 6, wherein the inventory item comprises a first inventory item, the inventory holder comprises a first inventory holder, and the method further comprises: checking whether the plurality of orders includes a request for a second inventory item of the plurality of inventory items, the second inventory item being stored by a second inventory holder disposed at the inventory holder; and wherein the first order and the second order are grouped based at least in part on one or more of the first order and the second order comprising the first inventory item and the second inventory item. 9. A non-transitory computer readable medium comprising logic operable when executed by a processor to: instructing the first mobile drive unit to transport the inventory holder to the inventory holder, the logic being responsive to a velocity of the one or more inventory items stored by the inventory holder; and instructing a second mobile drive unit to ship an order holder to the inventory holder, the logic responsive to an order comprising the one or more inventory items, wherein the second mobile drive unit moves the an order holder to receive one or more of said inventory items; and wherein the order holder comprises a first order holder and the logic is further operable to instruct a third mobile drive unit to transport a second order holder along the inventory rack, wherein the third mobile drive unit and the first order holder two mobile drive units move in the same direction and at the same time along the inventory holder; and Wherein, the speed also includes expected demand. 10. The computer readable medium of claim 9 , the logic further operable to designate the inventory holder to hold at one of a plurality of defined areas at an inventory holder while fulfilling a plurality of orders fixed. 11. The computer readable medium of claim 9, wherein: the speeds include a first speed; the one or more inventory items include one or more first inventory items; the inventory holders include a first inventory holder; and The logic is also operable to: calculating the first velocity of the one or more first inventory items; and instructing the first mobile drive unit based at least in part on determining that the first velocity of the one or more first inventory items is faster than a second velocity of one or more second inventory items stored by a second inventory holder and transporting the first inventory holder to the inventory holder. 12. The computer-readable medium of claim 9, wherein the velocity further comprises one or more of historical velocity, known demand, and expected demand. 13. The computer-readable medium of claim 9, wherein the inventory holder comprises a first inventory holder, the order holder comprises a first order holder, and the logic is further operable to: instructing the first mobile drive unit to transport a second inventory holder storing the one or more inventory items to the inventory holder; and instructing a third mobile drive unit to ship a second order holder to the inventory holder, wherein when the first order holder receives one or more of the inventory items from the first inventory holder, the The second order holder receives one or more of the inventory items from the second inventory holder, wherein the inventory items in the first inventory holder and the second inventory holder are the same .