Re-arrange stored inventory holders

Patent metadata

Field	Value
Publication number	US-9694976-B1
Application number	US-201615385766-A
Country	US
Kind code	B1
Filing date	Dec 20, 2016
Priority date	Sep 26, 2014
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

Inventory holders in an inventory system can be moved among differing storage positions. The moves can be performed by mobile drive units not otherwise transporting inventory holders directly to or from inventory stations. A free mobile drive unit can move an inventory holder not likely to be useful soon at any nearby station from a storage position near the station to a position farther away from the station. A mobile drive unit can move an inventory holder likely to be useful soon from a storage position farther away from one or more stations to a storage position nearby one or more stations.

First claim

What is claimed is:

1. An inventory system, comprising:
mobile drive units configured to move inventory holders that are configured to store inventory items; and
a management module configured to:
access a designated set of tasks comprising tasks designated for performance at a station that is configured for performance of a task related to one or more inventory items associated with an inventory holder when the inventory holder is positioned at the station;
instruct a first set of the mobile drive units to move respective inventory holders of a first set of inventory holders from respective storage locations to the station, the respective inventory holders of the first set of inventory holders meeting criteria of respective tasks of the designated set of tasks, each storage location for storing an inventory holder apart from the station when the inventory holder is not at the station;
determine a predicted set of tasks comprising tasks predicted to be designated for performance at the station; and
instruct a second set of the mobile drive units to move respective inventory holders of a second set of inventory holders from respective initial storage locations to respective subsequent storage locations further from the station, the respective inventory holders of the second set of inventory holders not meeting criteria of respective tasks of the predicted set of tasks.

2. The inventory system of claim 1 , wherein the station is a stow station for loading inventory items into the inventory holders;
wherein the predicted set of tasks determined by the management module comprises stowing tasks of loading inventory items into the inventory holders; and
wherein the management module is further configured to instruct the second set of the mobile drive units to move respective inventory holders lacking available space for the stowing tasks from respective initial storage locations to respective subsequent storage locations further from the stow station.

3. The inventory system of claim 2 , wherein the management module is configured to instruct a third set of the mobile drive units to move respective inventory holders having available space for the stowing tasks from respective initial storage locations to respective subsequent storage locations closer to the stow station.

4. The inventory system of claim 1 , wherein the station is a count station for counting inventory items of the inventory holders;
wherein the predicted set of tasks determined by the management module comprises counting tasks of counting inventory items of the inventory holders; and
wherein the management module is further configured to instruct the second set of the mobile drive units to move respective inventory holders lacking inventory bins with inventory items therein to be counted for the counting tasks from respective initial storage locations to respective subsequent storage locations further from the count station.

5. The inventory system of claim 4 , wherein the management module is configured to instruct a third set of the mobile drive units to move respective inventory holders having inventory bins with inventory items therein to be counted for the counting tasks from respective initial storage locations to respective subsequent storage locations closer to the count station.

6. The inventory system of claim 1 , wherein the station is a pick station for unloading inventory items from the inventory holders;
wherein the predicted set of tasks determined by the management module comprises picking tasks of unloading inventory items from the inventory holders; and
wherein the management module is further configured to instruct the second set of the mobile drive units to move respective inventory holders lacking inventory items for the picking tasks from respective initial storage locations to respective subsequent storage locations further from the pick station.

7. The inventory system of claim 6 , wherein the management module is configured to instruct a third set of the mobile drive units to move respective inventory holders having inventory items for the picking tasks from respective initial storage locations to respective subsequent storage locations closer to the pick station.

8. An inventory system comprising:
a plurality of mobile drive units configured to move a plurality of inventory holders configured to store inventory items, the plurality of mobile drive units configured to move the plurality of inventory holders among locations including a plurality of stations and a plurality of storage locations, each station of the plurality of stations including at least one station location configured to receive an inventory holder for completion of a task involving at least one inventory item associated with the inventory holder, each storage location of the plurality of storage locations configured to store an inventory holder when the inventory holder is not at a station location; and
a management module configured to:
determine possible movements of the plurality of inventory holders among the plurality of storage locations;
determine a utility of an arrangement of inventory holders in the plurality of storage locations resulting from each of the possible movements, wherein the utility is based at least in part on a utility score assigned to each of the possible movements, wherein the utility score of each possible movement is based on at least one of:
a drive time involved in the possible movement for a mobile drive unit;
an amount of time a mobile drive unit would deviate from other tasks to perform the possible movement;
an amount of distance a mobile drive unit would deviate from other tasks to perform the possible movement;
a change in distance of an inventory holder relative to a particular station provided by the possible movement;
a degree to which contents of an inventory holder moved by the possible movement match criteria or demands of a particular station;
a timeframe of the demands of a particular station;
future gains in total system efficiency provided by the possible movement; or
future losses in total system efficiency provided by the possible movement; and

instruct at least one of the plurality of mobile drive units to perform at least one of the possible movements based on the determined utility.

9. The inventory system of claim 8 , wherein the management module configured to instruct at least one of the plurality of mobile drive units to perform at least one of the possible movements based on the determined utility comprises the management module configured to instruct the at least one of the plurality of mobile drive units to perform the at least one of the possible movements having a utility score exceeding a threshold.

10. The inventory system of claim 8 , wherein the management module configured to instruct at least one of the plurality of mobile drive units to perform at least one of the possible movements based on the determined utility comprises the management module configured to instruct the at least one of the plurality of mobile drive units to perform the at least one of the possible movements having a highest utility score relative to other possible movements.

11. The inventory system of claim 8 , wherein the management module configured to determine possible movements of the plurality of inventory holders among the plurality of storage locations comprises the management module configured to determine possible movements of the plurality of inventory holders that meet criteria associated with tasks that are predicted to be associated with a particular station.

12. An inventory system comprising:
a plurality of mobile drive units configured to move a

Assignees

• Amazon Tech Inc

Inventors

• Wurman Peter R
• Brazeau Jeremiah David
• Farwaha Pardeep Singh
• Holt Ryan Alexander
• Durham Joseph W
• Enright John Joseph
• Glazkov Alex
• Holcomb Jared Brian

Classifications

• B65G1/0492

  with cars adapted to travel in storage aisles · CPC title

• B65G1/10

  with relatively movable racks to facilitate insertion or removal of articles {(cabinets with means for moving compartments up and down A47B51/00; cabinet system, e.g. consisting of cabinets arranged in a row with means to open or close passages between adjacent cabinets A47B53/02)} · CPC title

• B65G1/137 Primary

  with arrangements or automatic control means for selecting which articles are to be removed · CPC title

• G05B13/026

  using a predictor · CPC title

• G06Q10/087

  Inventory or stock management, e.g. order filling, procurement or balancing against orders · CPC title