System, apparatus and method for sequencing objects having RFID tags on a moving conveyor

• US 10,346,656 B2
• Filed: 12/17/2015
• Issued: 07/09/2019
• Est. Priority Date: 12/31/2014
• Status: Active Grant

• Current Assignee: Walmart Apollo, LLC (WalMart Inc.)
• Original Assignee: Walmart Apollo, LLC (WalMart Inc.)
• Inventors: Wilkinson, Bruce W.
• Primary Examiner(s): Cumbess, Yolanda R
• Application Number:
  US15/534,382
• Publication Number:
  US 20170372106A1
• Time in Patent Office: 1,300 Days
• Field of Search: None
• CPC Class Codes: B65G 2203/046 RFID
• CPC Class Codes: G05B 19/12 using record carriers
• CPC Class Codes: G05B 2219/2621 Conveyor, transfert line
• CPC Class Codes: G05B 2219/31197 Near field communication nfc
• CPC Class Codes: G05B 2219/40554 Object recognition to track object on conveyor
• 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 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10435 the interrogation device being positioned close to a conveyor belt or the like on which moving record carriers are passing conveying in accordance with bodily destination marks, see B65G47/46, sorting of objects carrying identity markings, see B07C5/34
• CPC Class Codes: G06K 7/10445 the record carriers being fixed to further objects, e.g. RFIDs fixed to packages, luggage, mail-pieces or work-pieces transported on a conveyor belt
• CPC Class Codes: G06K 7/10455 the record carriers being fixed to an endless tape or at least not fixed to further objects
• CPC Class Codes: G06Q 10/08 Logistics, e.g. warehousing, loading or distribution; Inventory or stock management

Abstract

In some embodiments, apparatuses and methods are provided herein useful to track objects on a moving conveyor system. In some embodiments, an RFID based tracking system comprises a conveyor system to move and transport objects along a conveyance path, wherein each object includes a near field only RFID tag associated therewith and identifying the object. Each near field only RFID tag is not coupled to a far field antenna such that it is not readable in a far field of RFID communication and communicates only in a near field of RFID communication. An RFID tag reader is positioned to attempt to read the near field only RFID tag of each object. And a control circuit processes reads of the near field only RFID tags by the first RFID reader to determine an order of the objects being conveyed.

Claims

1. A radio frequency identification (RFID) based tracking system comprising:

a conveyor system configured to move and transport a plurality of objects along a conveyance path, wherein each of the plurality of objects includes a near field only RFID tag associated therewith and identifying the object, wherein each near field only RFID tag is not coupled to a far field antenna such that it is not readable in a far field of RFID communication and communicates only in a near field of RFID communication;

a first RFID tag reader positioned relative to a first portion of the conveyor system and configured to attempt to read the near field only RFID tag of each of the plurality of objects; and

a control circuit configured to process reads of the plurality of near field only RFID tags by the first RFID reader to determine an order of the plurality of objects being conveyed.

2. The system of claim 1 wherein each of the plurality of objects comprises a container containing a plurality of items therein, and each of the plurality of items includes an RFID tag associated therewith, identifying the item, and configured to be read in the near field and the far field of RFID communication.

3. The system of claim 2 further comprising:

one or more additional RFID tag readers positioned relative to a second portion of the conveyor system that is upstream along the path of conveyance relative to the first portion of the conveyor system and is configured to broadcast signaling to the RFID tag of each of the plurality of items in the far field of RFID communications to attempt to transition the RFID tags to a non-readable state prior to the objects being conveyed into a far field read range of the first RFID reader.

4. The system of claim 3 wherein the one or more additional RFID tag readers broadcast read signals to attempt to read the RFID tag of each of the plurality of items in the far field of RFID communications, the RFID tag of each of the plurality of items being configured to transition to the non-readable state after responding to a read signal.

5. The system of claim 3 wherein the one or more additional RFID tag readers broadcast read state change command signals, the RFID tag of each of the plurality of items being configured to transition to the non-readable state in response to receiving a read state change command signal.

6. The system of claim 3 wherein the control circuit is configured to discard reads of any of the RFID tags of the plurality of items read by the first RFID reader.

7. The system of claim 3 wherein the second location and the first location of the conveyor system are separated a distance, such that the RFID tags of the plurality of items contained within a given object will receive the signaling from the one or more additional RFID readers prior to the RFID tags of the plurality of items contained within the given object being readable by the first RFID reader.

8. The system of claim 1 wherein the first RFID reader is configured to read RFID tags in the near field of RFID communication and in the far field of RFID communication.

9. The system of claim 1 wherein each near field only RFID tag uniquely identifies its corresponding one of the plurality of objects.

10. The system of claim 1 wherein the near field only RFID tag of each of the plurality of objects is positioned at or proximate to a bottom surface of the object.

11. The system of claim 1 wherein the first RFID tag reader is positioned underneath the conveyor system at the first portion of the conveyor system such that the near field only RFID tags will be able to respond to read signals from the first RFID reader in the near field of RFID communication as the plurality of objects pass over the first RFID reader.

12. The system of claim 1 wherein the plurality of objects comprise objects having one or both of a plurality of different sizes and a plurality of different dielectric characteristics.

13. The system of claim 1 wherein the control circuit is configured to:

receive an indication of a read time when a read response is received at the first RFID reader from the near field only RFID tag of each of the plurality of objects; and

process the indication of the read time and a read response of each of the plurality of objects to determine the order of the plurality of objects being conveyed.

14. A method of tracking objects using radio frequency identification (RFID) communications, the method comprising:

transporting a plurality of objects along a conveyance path of a conveyor system, wherein each of the plurality of objects includes a near field only RFID tag associated therewith and identifying the object, wherein each near field only RFID tag is not coupled to a far field antenna such that it is not readable in a far field of RFID communication and communicates only in a near field of RFID communication;

sending, by a first RFID tag reader positioned relative to a first portion of the conveyor system, read signals to attempt to read the near field only RFID tag of each of the plurality of objects;

receiving, by the first RFID reader, responses from the near field only RFID tag of each of the plurality of objects when the near field only RFID tag is within the near field of RFID communications of the first RFID reader; and

processing, by a control circuit, the responses from the plurality of near field only RFID tags to determine an order of the plurality of objects being conveyed.

15. The method of claim 14 wherein each of the plurality of objects comprises a container containing a plurality of items therein, and each of the plurality of items includes an RFID tag associated therewith, identifying the item and configured to be read in the near field and the far field of RFID communication.

16. The method of claim 15 further comprising:

broadcasting, by one or more additional RFID tag readers positioned relative to a second portion of the conveyor system that is upstream along the path of conveyance relative to the first portion of the conveyor system, signals to the RFID tag of each of the plurality of items in the far field of RFID communications to attempt to transition the RFID tags to a non-readable state prior to the objects being conveyed into a far field read range of the first RFID reader.

17. The method of claim 16 wherein the signals comprise read signals to attempt to read the RFID tag of each of the plurality of items in the far field of RFID communications, wherein the method further comprises transitioning the one or more RFID tags of the plurality of items to the non-readable state after responding to a read signal.

18. The method of claim 16 wherein the signals comprise read state change command signals, the RFID tag of each of the plurality of items being configured to transition to the non-readable state in response to receiving a read state change command signal.

19. The method of claim 16 further comprising discarding, by the control circuit, reads of any of the RFID tags of the plurality of items read by the first RFID reader.

20. The method of claim 16 wherein the second location and the first location of the conveyor system are separated a distance, such that the RFID tags of the plurality of items contained within a given object will receive the signals from the one or more RFID readers prior to the RFID tags of the plurality of items contained within the given object being readable by the first RFID reader.

21. The method of claim 14 wherein the first RFID reader is configured to read RFID tags in the near field of RFID communication and in the far field of RFID communication.

22. The method of claim 14 wherein each near field only RFID tag uniquely identifies its corresponding one of the plurality of objects.

23. The method of claim 14 wherein the near field only RFID tag of each of the plurality of objects is positioned at or proximate to a bottom surface of the object.

24. The method of claim 14 wherein the first RFID tag reader is positioned underneath the conveyor system at the first portion of the conveyor system such that the near field only RFID tags will be able to respond to read signals from the first RFID reader in the near field of RFID communication as the plurality of objects pass over the first RFID reader.

25. The method of claim 14 wherein the plurality of objects comprise objects having one or both of a plurality of different sizes and a plurality of different dielectric characteristics.

26. The method of claim 14 further comprising:

receiving, by the control circuit, an indication of a read time when a read response is received at the first RFID reader from the near field only RFID tag of each of the plurality of objects; and

wherein the processing step comprises processing, by the control circuit, the indication of the read time and a read response of each of the plurality of objects to determine the order of the plurality of objects being conveyed.

27. An apparatus comprising:

a networked control circuit coupled to a memory device and configured to;

automatically receive a read response received at a first radio frequency identification (RFID) reader from a near field only RFID tag of each of a plurality of objects being transported by a conveyor system along a conveyance path, each near field only RFID tag associated with and identifying a given one of the plurality of objects, and each near field only RFID tag being not coupled to a far field antenna such that it is not readable in a far field of RFID communication and communicates only in a near field of RFID communication, wherein the first RFID reader is positioned relative to a first portion of the conveyor system in order that the near field only RFID tag of each of the plurality of objects responds to a read signal from the first RFID reader when the near field only RFID tag is within the near field of RFID communication of the first RFID reader; and

automatically process the read response of each of the plurality of objects to determine an order of the plurality of objects being conveyed on the conveyor system.

28. The apparatus of claim 27 wherein the networked control circuit is configured to:

automatically receive an indication of a read time when the read response is received at the first RFID reader from the near field only RFID tag of each of the plurality of objects; and

automatically process the indication of the read time and the read response of each of the plurality of objects to determine the order of the plurality of objects being conveyed on the conveyor system.

29. The apparatus of claim 27 wherein each of the plurality of objects comprises a container containing a plurality of items therein, and each of the plurality of items includes an RFID tag associated therewith and corresponding thereto, and wherein one or more additional RFID readers are used to broadcast signaling to attempt to transition the RFID tag of each of the plurality of items to a non-readable state before the first RFID reader can read the RFID tag of each of the plurality of items, and

wherein the networked control circuit is configured to automatically discard reads of any of the RFID tags of the plurality of items read by the first RFID reader that were not transitioned to the non-readable state.

30. A method comprising:

by a networked control circuit coupled to a memory device,

automatically receiving a read response received at a first radio frequency identification (RFID) reader from a near field only RFID tag of each of a plurality of objects being transported by a conveyor system along a conveyance path, each near field only RFID tag associated with and identifying a given one of the plurality of objects, and each near field only RFID tag being not coupled to a far field antenna such that it is not readable in a far field of RFID communication and communicates only in a near field of RFID communication, wherein the first RFID reader is positioned relative to a first portion of the conveyor system in order that the near field only RFID tag of each of the plurality of objects responds to a read signal from the first RFID reader when the near field only RFID tag is within the near field of RFID communication of the first RFID reader; and

automatically processing the read response of each of the plurality of objects to determine an order of the plurality of objects being conveyed on the conveyor system.