Automatic drawer state detection

• US 9,235,740 B1
• Filed: 12/15/2014
• Issued: 01/12/2016
• Est. Priority Date: 12/15/2014
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Graybill, Jules Cook, Lauka, Wesley Scott, Russell, Ryan Scott, Phillips, Jonathan David
• Primary Examiner(s): Le, Thien M
• Assistant Examiner(s): Brown, Claude J
• Application Number:
  US14/570,999
• Time in Patent Office: 393 Days
• Field of Search: 235/385
• US Class Current: 1/1
• CPC Class Codes: G05B 19/12 using record carriers
• CPC Class Codes: G05B 2219/31319 Use data groups as inventory control value, adapt inventory need to new data
• CPC Class Codes: G06K 7/10297 arrangements for handling protocols designed for non-contact record carriers such as RFIDs NFCs, e.g. ISO/IEC 14443 and 18092 cryptographic protocols H04L9/00; network security protocols H04L63/00; real-time communication protocols in data switching networks H04L65/00; network protocols for data switching network services H04L67/00
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications
• CPC Class Codes: G06K 7/10396 the interrogation device being wearable, e.g. as a glove, bracelet, or ring wearable aerials in general H01Q1/27
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: G08C 17/02 using a radio link
• CPC Class Codes: H01H 2300/032 using RFID technology in switching devices
• CPC Class Codes: H01H 9/167 Circuits for remote indication
• CPC Class Codes: H04Q 2209/47 using RFID associated with sensors
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/14 Protecting elements, switches, relays or circuit breakers

Abstract

An inventory system can include radio frequency identification (RFID) tags and RFID tuners that can be brought into interacting proximity with one another to provide input or other information about the location or other condition of movable elements within the inventory system. For example, a closed or at least partially open state of a drawer can be determined based on signals from an RFID tag when the RFID tag and a corresponding RFID tuner are mounted on opposing faces of the drawer and a compartment that receives the drawer.

Claims

1. An inventory management system comprising:

an inventory holder having a compartment;

a drawer slidingly received in the compartment;

a radio frequency identification (RFID) tag associated with a first surface of one of the drawer or the compartment;

an RFID reader configured to receive radiofrequency signals from the RFID tag;

an RFID tuner associated with a second surface of the other of the drawer or the compartment, the RFID tuner configured to interact with the RFID tag such that the RFID reader receives a first signal from the RFID tag when the RFID tag is at a first position relative to the RFID tuner and such that the RFID reader receives a second signal from the RFID tag when the RFID tag is at a second position relative to the RFID tuner, the first and second signals being different from each other and the first and second positions being different from each other; and

a management module configured to;

access, via the RFID reader, a signal received from the RFID tag;

determine whether the received signal is the first signal or the second signal from the RFID tag;

determine a state of closure of the drawer relative to the compartment based at least in part on the received signal; and

instruct a response based at least in part on the determined state of closure.

2. The inventory management system of claim 1, wherein at least one of:

(i) a plurality of RFID tags are associated with the first surface or (ii) a plurality of RFID tuners are associated with the second surface, and wherein the response comprises communicating a percentage of closure of the drawer.

3. The inventory management system of claim 1, wherein the inventory management system further comprises a mobile drive unit configured to move the inventory holder, wherein the response comprises instructing the mobile drive unit so as to prevent movement of the inventory holder while the state of closure of the drawer indicates that the drawer is at least partially open.

4. The inventory management system of claim 1, wherein the response comprises associating an action with the drawer or a location of the drawer based at least in part on a change in the state of closure of the drawer.

5. The inventory management system of claim 1, wherein the management module is further configured to identify an inventory item, wherein the response comprises associating the identified inventory item with the drawer or a location of the drawer based at least in part on a change in the state of closure of the drawer.

6. The inventory management system of claim 1, wherein the management module is further configured to identify an inventory item to be stowed in the inventory holder, wherein the response comprises associating, based at least in part on a change in the state of closure of the drawer, the drawer or a location of the drawer with a location in which the identified inventory item is stowed.

7. The inventory management system of claim 1, wherein the management module is further configured to identify an inventory item to be removed from the inventory holder, wherein the response comprises associating, based at least in part on a change in the state of closure of the drawer, the drawer or a location of the drawer with a location from which the identified inventory item is removed.

8. The inventory management system of claim 1, wherein the management module is further configured to identify an inventory item to be counted in the inventory holder, wherein the response comprises associating, based at least in part on a change in the state of closure of the drawer, the drawer or a location of the drawer with a location in which the identified inventory item is counted.

9. The inventory management system of claim 1, wherein the management module is further configured to identify the drawer or a location of the drawer as a target for an action, wherein the response comprises confirming, based at least in part on a change in the state of closure of the drawer, that the drawer or the location of the drawer was used for the action.

10. A method comprising:

receiving, by a radiofrequency identification (RFID) reader, an RFID signal from an RFID tag interacting with an RFID tuner, the RFID tag being associated with one of a moveable object or a receiving surface and the RFID tuner being associated with the other of the moveable object or the receiving surface, wherein a first RFID signal is received when the RFID tag is at a first distance relative to the RFID tuner, and a second RFID signal is received when the RFID tag is at a second distance relative to the RFID tuner; and

identifying a position of the moveable object relative to the receiving surface based at least in part on the received RFID signal,

wherein the RFID tag is proximally located with the RFID tuner at the first distance such that the first RFID signal comprises a first frequency band, and the RFID tag is not proximally located with the RFID tuner at the second distance such that the second RFID signal comprises a second frequency band, the first and second frequency bands being different.

11. The method of claim 10, further comprising identifying a movement of the moveable object relative to the receiving surface based at least in part on a change of the received RFID signal between the first RFID signal and the second RFID signal.

12. The method of claim 10, wherein a plurality of RFID tags are associated with the one of the moveable object or the receiving surface and a plurality of RFID tuners are associated with the other of the moveable object or the receiving surface;

wherein, for each RFID tag, the first RFID signal is received when the RFID tag is at the first distance relative to one of the plurality of RFID tuners; and

wherein identifying the position of the moveable object relative to the receiving surface based at least in part on the received RFID signal comprises determining the position of the moveable object relative to the receiving surface based on a number of received first RFID signals.

13. The method of claim 10, wherein a plurality of RFID tuners are associated with the other of the moveable object or the receiving surface;

wherein, for each of the plurality of RFID tuners, a unique RFID signal is received when the RFID tag is at the first distance relative to the RFID tuner; and

wherein identifying the position of the moveable object relative to the receiving surface based at least in part on the received RFID signal comprises determining the position of the moveable object relative to the receiving surface based on the unique RFID signal received from the RFID tag.

14. The method of claim 10, wherein the receiving surface comprises a portion of a compartment forming a portion of an inventory holder configured to be moved by a mobile drive unit, and the moveable object comprises a drawer configured to be received in the compartment.

15. A non-transitory computer-readable storage medium having stored therein instructions that, when executed by one or more processors of a computer system, cause the computer system to at least:

receive, by a radiofrequency identification (RFID) reader, an RFID signal from an RFID tag interacting with an RFID tuner, the RFID tag being associated with one of a mobile object or a receiving surface and the RFID tuner being associated with the other of the mobile object or the receiving surface, wherein a first RFID signal is received when the RFID tag is proximally located with the RFID tuner, and a second RFID signal is received when the RFID tag is not proximally located with the RFID tuner; and

associate, based at least in part on the first RFID signal received from the RFID tag proximally located with the RFID tuner, the mobile object with the receiving surface.

16. The non-transitory computer-readable storage medium of claim 15, wherein the mobile object is a container configured to receive inventory items for transfer relative to an inventory system and the receiving surface is a loading location for receiving the container for receipt of inventory items.

17. The non-transitory computer-readable storage medium of claim 15, wherein the instructions further cause the computer system to receive a third RFID signal from a second RFID tag, the second RFID tag attached to the mobile object and the third RFID signal from the second RFID tag identifying the mobile object.

18. The non-transitory computer-readable storage medium of claim 15, wherein the RFID tag is a first RFID tag associated with the mobile object and the RFID tuner is a first RFID tuner associated with the receiving surface, and wherein the instructions further cause the computer system to:

receive, by the RFID reader, a third RFID signal from a second RFID tag interacting with a second RFID tuner, the second RFID tag being associated with the receiving surface, and the second RFID tuner being associated with the mobile object;

identify the receiving surface based on the third RFID signal received from the second RFID tag associated with the receiving surface and interacting with the second RFID tuner associated with the mobile object; and

identify the mobile object based on the first RFID signal received from the first RFID tag associated with the mobile object and interacting with the first RFID tuner associated with the receiving surface.