Merchandise event monitoring via wireless tracking

• US 9,916,556 B2
• Filed: 04/12/2016
• Issued: 03/13/2018
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Walmart Apollo, LLC (WalMart Inc.)
• Original Assignee: Wal-Mart Stores Texas LLC (WalMart Inc.)
• Inventors: Stiefel, Thomas E., Wilkinson, Bruce W., Jones, Nicholaus Adam
• Primary Examiner(s): Nguyen, Nam V
• Application Number:
  US15/096,928
• Publication Number:
  US 20160224814A1
• Time in Patent Office: 700 Days
• Field of Search: 340 101, 3405731, 3408154, 340 81, 702 41, 455 39, 455 73, 345204
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications
• CPC Class Codes: G06K 7/10475 arrangements to facilitate interaction with further interrogation devices, e.g. such that at least two interrogation devices may function and cooperate in a network of such devices
• CPC Class Codes: G06Q 10/08 Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders

Abstract

Item movement is determined via wireless tracking using RFID data from at least one RFID reader. The RFID data associates RFID tag information with each antenna of the RFID reader that receives the tag information. At least one processer is configured to identify a first appearance of unique tag information in the RFID data. Items may be grouped when their first appearance in RFID data and their antenna association indicates that they first appear in a location within a predetermined amount of time, as indicated by RFID data, and/or when they have all moved from a previous location within a predetermined amount of time, as indicated by different RFID data. A group designation comprises the relevant unique tag information, which may be stored in memory along with a time stamp.

Claims

1. A method for monitoring movement of two or more items within a facility via wireless tracking, the method comprising:

determining movement of a first RFID tag in response to detecting the first RFID tag in a first read zone defined by a first antenna of an RFID reader and subsequently detecting the first RFID tag in a second read zone defined by a second antenna of the RFID reader;

detecting a second RFID tag in the second read zone within a first time period of detecting the first RFID tag in the second read zone;

determining whether the second RFID tag was previously detected in the first read zone in response to detection of the second RFID tag in the second read zone within the first time period;

in response to determining that the second RFID tag was previously detected in the first read zone, forming a group including the first RFID tag information associated with the first RFID tag and second RFID tag information associated with the second RFID tag; and

tracking movement of the group,

identifying, by the processor, an appearance of the first RFID tag information in a third set of RFID data associated with a third read zone;

identifying, by the processor, an appearance of the second RFID tag information in a fourth set of RFID data associated with a fourth read zone;

checking, by the processor, for an appearance of the first RFID tag information in the fourth set of RFID data;

checking, by the processor, for an appearance of the second RFID tag information in the third set of RFID data;

determining non-appearance of the second RFID tag information in the third set of RFID data and non-appearance of the first RFID tag information in the fourth set of RFID data for a first quantity of time; and

terminating the group,

wherein the first RFID tag is detected in the first read zone based on identifying the first RFID tag information in a first set of RFID data received by a processing device in communication with the RFID reader and the first RFID tag is detected in the second read zone based on identifying the first RFID tag information in a second set of RFID data received by a processing device in communication with the RFID reader; and

wherein the second RFID tag is detected in the first read zone based on identifying the second RFID tag information in the first set of RFID data received by the processing device in communication with the RFID reader and the second RFID tag is detected in the second read zone based on identifying the second RFID tag information in the second set of RFID data received by the processing device in communication with the RFID reader.

2. The method of claim 1, further comprising:

determining non-movement of the first RFID tag and the second RFID tag in response to detecting that the first RFID tag and the second RFID tag remain in the second read zone for a second time period; and

in response to determining non-movement of the first RFID tag and the second RFID tag, terminating the group.

3. The method of claim 1, further comprising:

determining movement of the first RFID tag and the second RFID tag in response to failing to detect the first RFID tag and the second RFID tag in the second read zone after a second time period; and

in response to determining movement of the first RFID tag and the second RFID tag, terminating the group.

4. The method of claim 1, further comprising:

filtering, by the processor, the first set of RFID data to eliminate shadow data.

5. A method for monitoring movement of two or more items within a facility via wireless tracking, the method comprising:

determining movement of a first RFID tag in response to detecting the first RFID tag in a first read zone defined by a first antenna of an RFID reader and subsequently detecting the first RFID tag in a second read zone defined by a second antenna of the RFID reader;

detecting a second RFID tag in the second read zone within a first time period of detecting the first RFID tag in the second read zone;

determining whether the second RFID tag was previously detected in the first read zone in response to detection of the second RFID tag in the second read zone within the first time period;

in response to determining that the second RFID tag was previously detected in the first read zone, forming a group including the first RFID tag information associated with the first RFID tag and second RFID tag information associated with the second RFID tag;

tracking movement of the group;

identifying, by the processor, an appearance of the first RFID tag information and an appearance of the second RFID tag information in a third set of RFID data received from a second RFID reader comprising at least one antenna, wherein the at least one antenna of the second RFID reader and the at least two antennas of the first RFID reader have non-overlapping read zones; and

checking whether the appearance of first RFID tag information in the third set of RFID data occurred within a first quantity time of the appearance of the second RFID tag information in the third set of RFID data;

checking whether the appearance of the first RFID tag information and the second RFID tag information in the third set of RFID data from the second RFID reader occurred within a second quantity of time of the appearances of the first RFID tag information or the second RFID tag information in the first set of RFID data from the first RFID reader; and

in response to determining that the appearances in the third set of RFID data occurred within the first quantity of time and the second quantity of time, determining that the group including first and second RFID tags moved,

wherein the first RFID tag is detected in the first read zone based on identifying the first RFID tag information in a first set of RFID data received by a processing device in communication with the RFID reader and the first RFID tag is detected in the second read zone based on identifying the first RFID tag information in a second set of RFID data received by a processing device in communication with the RFID reader; and

wherein the second RFID tag is detected in the first read zone based on identifying the second RFID tag information in the first set of RFID data received by the processing device in communication with the RFID reader and the second RFID tag is detected in the second read zone based on identifying the second RFID tag information in the second set of RFID data received by the processing device in communication with the RFID reader.

6. The method of claim 5, further comprising:

calculating by the processor, a confidence score based on a comparison of the appearances of the first and second RFID tag information in the first set of RFID data and the second set of RFID data.

7. The method of claim 5, further comprising:

triggering, by the processor, an alert based on determining that the group including the first and second RFID tags has moved.

8. The method of claim 5, wherein a plurality of groups including the group are formed to track the movement of a plurality of RFID tags including the first and second RFID tags through the facility, wherein the method further comprises:

analyzing, by the processor, at least one of formation or termination of one or more of the plurality of groups to identify a traffic flow pattern within the facility.

9. The method of claim 5, further comprising:

determining movement of the first RFID tag and the second RFID tag in response to failing to detect the first RFID tag and the second RFID tag in the second read zone after a second time period; and

in response to determining movement of the first RFID tag and the second RFID tag, terminating the group.

10. The method of claim 5, further comprising:

filtering, by the processor, the first set of RFID data to eliminate shadow data.

11. The method of claim 5, further comprising:

determining non-movement of the first RFID tag and the second RFID tag in response to detecting that the first RFID tag and the second RFID tag remain in the second read zone for a second time period; and

in response to determining non-movement of the first RFID tag and the second RFID tag, terminating the group.

12. A system for monitoring movement of two or more items within a facility via wireless tracking, the system comprising:

a first RFID reader comprising at least two antennas configured to read tag information for an RFID tag;

a processor in communication with the first RFID reader;

a memory in communication with the processor;

the processor configured to;

determine movement of a first RFID tag in response to detecting the first RFID tag in a first read zone defined by a first antenna of an RFID reader and subsequently detecting the first RFID tag in a second read zone defined by a second antenna of the RFID reader;

detect a second RFID tag in the second read zone within a first time period of detecting the first RFID tag in the second read zone;

determine whether the second RFID tag was previously detected in the first read zone in response to detection of the second RFID tag in the second read zone with the first time period; and

in response to determining that the second RFID tag was previously detected in the first read zone, form a group including the first and second RFID tags,

wherein the first and second RFID tags are detected in the first read zone based on identifying the first RFID tag information and the second RFID tag information in a first set of RFID data received by a processing device in communication with the first RFID reader,

wherein the first RFID tag and the second RFID tag are detected in the second read zone based on identifying the first RFID tag information and the second RFID tag information in a second set of RFID data received by a processing device in communication with the RFID reader, and

wherein the processor is configured to;

identify an appearance of the first RFID tag information in a third set of RFID data associated with a third read zone;

identify an appearance of the second RFID tag information in a fourth set of RFID data associated with a fourth read zone;

check for an appearance of the first RFID tag information in the fourth set of RFID data;

check for an appearance of the second RFID tag information in the third set of RFID data;

determine non-appearance of the second RFID tag information in the third set of RFID data and non-appearance of the first RFID tag information in the fourth set of RFID data for a first quantity of time; and

terminate the group.

13. The system of claim 12, wherein the processor is further configured to:

determine non-movement of the first RFID tag and the second RFID tag in response to detecting that the first RFID tag and the second RFID tag remain in the second read zone for a second time period; and

in response to determining non-movement of the first RFID tag and the second RFID tag, terminate the group.

14. The system of claim 12, wherein the processor is further configured to:

determining movement of the first RFID tag and the second RFID tag in response to failing to detect the first RFID tag and the second RFID tag in the second read zone after a second time period; and

in response to determining movement of the first RFID tag and the second RFID tag, terminating the group.

15. A system for monitoring movement of two or more items within a facility via wireless tracking, the system comprising:

a first RFID reader comprising at least two antennas configured to read tag information for an RFID tag;

a processor in communication with the first RFID reader;

a memory in communication with the processor;

the processor configured to;

determine movement of a first RFID tag in response to detecting the first RFID tag in a first read zone defined by a first antenna of an RFID reader and subsequently detecting the first RFID tag in a second read zone defined by a second antenna of the RFID reader;

detect a second RFID tag in the second read zone within a first time period of detecting the first RFID tag in the second read zone;

determine whether the second RFID tag was previously detected in the first read zone in response to detection of the second RFID tag in the second read zone with the first time period; and

in response to determining that the second RFID tag was previously detected in the first read zone, form a group including the first and second RFID tags;

a second RFID reader having at least one antenna,

wherein the first and second RFID tags are detected in the first read zone based on identifying the first RFID tag information and the second RFID tag information in a first set of RFID data received by a processing device in communication with the first RFID reader,

wherein the first RFID tag and the second RFID tag are detected in the second read zone based on identifying the first RFID tag information and the second RFID tag information in a second set of RFID data received by a processing device in communication with the RFID reader, and

wherein the processor is configured to;

identify an appearance of the first RFID tag information and an appearance of the second RFID tag information in a third set of RFID data received from a second RFID reader comprising at least one antenna, wherein the at least one antenna of the second RFID reader and the at least two antennas of the first RFID reader have non-overlapping read zones; and

check whether the appearance of first RFID tag information in the third set of RFID data occurred within a first quantity of time of the appearance of the second RFID tag information in the third set of RFID data;

check whether the appearance of the first RFID tag information and the second RFID tag information in the third set of RFID data from the second RFID reader occurred within a second quantity of time of the appearances of the first RFID tag information or the second RFID tag information in the first set of RFID data from the first RFID reader; and

in response to determining that the appearances in the third set of RFID data occurred within the first quantity of time and the second quantity of time, determine that the group including first and second RFID tags moved.

16. The system of claim 15, wherein the processor is further configured to:

determine non-movement of the first RFID tag and the second RFID tag in response to detecting that the first RFID tag and the second RFID tag remain in the second read zone for a second time period; and

in response to determining non-movement of the first RFID tag and the second RFID tag, terminate the group.

17. The system of claim 15, wherein the processor is further configured to:

determining movement of the first RFID tag and the second RFID tag in response to failing to detect the first RFID tag and the second RFID tag in the second read zone after a second time period; and

in response to determining movement of the first RFID tag and the second RFID tag, terminating the group.

18. A method for monitoring movement of two or more items within a facility via wireless tracking, the method comprising:

receiving a first set of RFID data from a first RFID reader comprising at least two antennas configured to read tag information of an RFID tag, the first set of RFID data including tag information of one or more RFID tags detected by a first antenna of the at least two antennas of the first RFID reader, the first set of RFID data further associating the tag information with the first antenna of the first RFID reader that read the one or more RFID tags;

receiving a second set of RFID data from the first RFID reader, the second set of RFID data including tag information of the one or more RFID tags detected by a second antenna of the at least two antennas of the first RFID reader, the second set of RFID data further associating the tag information with the second antenna of the first RFID reader that read the one or more RFID tags;

detecting movement of the one or more RFID tags by;

(i) identifying, using a processor in communication with the first RFID reader, an appearance of a first unique tag information corresponding to a first RFID tag in the first set of RFID data prior to an appearance of the first unique tag information in the second set of RFID data;

(ii) determining movement of the first RFID tag from a first location within a read zone of the first antenna to the a second location within a read zone of the second antenna;

(iii) identifying, using the processor, an appearance of a second unique tag information corresponding to a second RFID tag in the first set of RFID data within a first quantity of time of the appearance of the first unique tag information in the first set of RFID data;

(iv) identifying, using the processor, an appearance of the second unique tag information in the second set of RFID data within the first quantity of time of the appearance of the first unique tag information in the second set of RFID data;

(v) determining movement of the second RFID tag with the first RFID tag;

(vi) in response to determining movement of the second RFID tag with the first RFID tag, designating, using the processor, a first group designation comprising the first unique tag information and the second unique tag information; and

(vii) storing in memory the first group designation, a first time index indicating a formation time at which the first group is designated, and a first event indicator indicating formation of a first group,

(viii) identifying, by the processor, an appearance of the first unique tag information in a third set of RFID data;

(ix) identifying, by the processor, an appearance of the second unique tag information in a fourth set of RFID data;

(x) checking, by the processor, for an appearance of the first unique tag information in the fourth set of RFID data;

(xi) checking, by the processor, for an appearance of the second unique tag information in the third set of RFID data;

(xii) determining non-appearance of the second unique tag information in the third set of RFID data and non-appearance of the first unique tag information in the fourth set of RFID data for a second quantity of time;

(xiii) terminating the first group comprising the first unique tag information and the second unique tag information; and

(xix) storing in memory the first group designation, a second event indicator indicating termination of the first group, and a second time index indicating a termination time at which the first group is terminated.

19. The method of claim 18, further comprising:

checking, by the processor, the second set of RFID data for an appearance of the first unique tag information and for an appearance of the second unique tag information for a second quantity of time;

determining non-movement of the first RFID tag and the second RFID tag; and

in response to determining non-movement of the first RFID tag and the second RFID tag, storing, in memory, the first group designation including the first unique tag information and the second unique tag information, a second time index indicating a termination time at which the first group is terminated, and a second event indicator indicating the termination of the first group.

20. The method of claim 18, further comprising:

checking, by the processor, the first set of RFID data for an appearance of the first unique tag information and for an appearance of the second unique tag information;

identifying non-appearance of either the first unique tag information or the second unique tag information for a second quantity of time; and

storing, in memory, the first group designation including the first unique tag information and the second unique tag information, a second time index, and a second event indicator, wherein the second event indicator indicates the termination of the first group.