Method and system for tracking clustered items

• US 6,496,806 B1
• Filed: 12/16/1999
• Issued: 12/17/2002
• Est. Priority Date: 12/16/1999
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: Samsys Technologies Incorporated
• Inventors: Horwitz, Clifford A., Davidson, William E.
• Primary Examiner(s): BARTUSKA, FRANCIS JOHN
• Application Number:
  US09/464,071
• Time in Patent Office: 1,097 Days
• Field of Search: 705/22, 705/28, 705/29, 235/385, 340/10-- 1
• US Class Current: 705/28
• CPC Class Codes: G06K 17/0029 the arrangement being specially adapted for wireless interrogation of grouped or bundled articles tagged with wireless record carriers
• 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

A method and system for tracking each item in a cluster of items. Each item has an associated item ID. The method and system involve the following steps. Storing a plurality of item records. The plurality of item records includes, for each item in the cluster of items, an associated item record for storing the associated item ID for the item. Each item record in the plurality of records is then linked to the other item records in the plurality of item records. Using the associated item record for each item in the threshold number of items, and the link between each item record and the other item records, the item records for the associated item ID of each item in the cluster that are not in the threshold number of items are determined.

Claims

1. A method of tracking each item in a cluster of items, each item having an associated item ID, the method comprising:

(a) storing a plurality of item records, the plurality of item records including, for each item in the cluster of items, an associated item record for storing the associated item ID for the item;

(b) linking each item record in the plurality of item records to the other item records in the plurality of item records;

(c) reading the associated item ID from each item in a threshold number of items in the cluster of items;

(d) determining the associated item record for each item in the threshold number of items using the associated item ID from each item read in step (c); and

,

(e) determining the associated item record for the associated item ID of each item in the cluster and not in the threshold number of items from the item records determined in step (d) using the link established in step (b).

2. The method as defined in claim 1 wherein

step (a) comprises storing a unique cluster ID for the cluster of items in a cluster record;

step (b) comprises linking the cluster record to each item record in the plurality of item records; and

step (e) comprises determining the cluster record linked to each item record determined in step (d), and then determining each item record associated with the cluster ID and not determined in step (d).

3. The method as defined in claim 2 wherein a threshold minimum is defined, the threshold minimum being a minimum number of items in the threshold number of items.

4. The method as defined in claim 3 wherein a tag is attached to each item, the tag bearing the associated item ID for the item.

5. The method as defined in claim 4 wherein the tag attached to each item is a RFID tag for transmitting the associated item ID to a tag reader.

6. The method as defined in claim 2 wherein steps (a), (b) and (c) are executed in a data processor.

7. The method as defined in claim 6 wherein each RFID tag is a read/write tag.

8. The method as defined in claim 7 wherein step (a) comprises storing the cluster ID in a cluster record field on each tag of each item in the cluster of items.

9. The method as defined in claim 7 wherein the items are clustered by being held in a common holding means.

10. The method as defined in claim 9 wherein the common holding means is movable by a transport means;

the tag reader is mounted on the transport means, and step (c) comprises reading the associated item ID for each item in the threshold number of items while the common holding means holding the cluster of items is held by the transport means.

11. The method as defined in claim 10 further comprising the step of tracking the location of the common holding means by determining the location of the transport means.

12. The method as defined in claim 11 wherein the transport means moves the common holding means within a storage space having a set of spaced location tags, each location tag being location at an associated location within the storage space and being operable to transmit location information to the tag reader on the transport means.

13. A system for tracking each item in a cluster of items, each item having an associated item ID, the system comprising:

(a) storage means for storing a plurality of item records, the plurality of item records including, for each item in the cluster of items, an associated item record for storing the associated item ID for the item;

(b) linking means for linking each item record in the plurality of item records to the other item records in the plurality of item records;

(c) reading means for reading the associated item ID from each line in a threshold number of items in the cluster of items; and

(d) processing means for

(i) determining the associated item record for each item in the threshold number of items using the associated item ID read by the reading means, and

(ii) determining the associated item record for the associated item ID of each item in the cluster and not in the threshold number of items from the item records determined in step (d) (i) using the link established by the linking means in step (b).

14. The system as defined in claim 13 wherein

the storage means is operable to store a unique cluster ID for the cluster of items in a cluster record;

the linking means is operable to link the cluster record to each item record in the plurality of item records; and

the processing means is operable to determine the cluster record linked to each item record determined in step (d) (i), and then to determine each item record associated with the cluster ID and not determined in step (d) (i).

15. The system as defined in claim 14 wherein a threshold minimum is defined, the threshold minimum being a minimum number of items in the threshold number of items.

16. The system as defined in claim 15 wherein a tag is attached to each item, the tag bearing the associated item ID for the item.

17. The system as defined in claim 16 wherein the tag attached to each item is a RFID tag for transmitting the associated item ID to a tag reader.

18. The system as defined in claim 17 wherein a data processor executes steps (a), (b) and (d).

19. The system as defined in claim 18 wherein each RFID tag is a read/write tag.

20. The system as defined in claim 19 wherein the storage means is operable to store the cluster ID in a cluster record field on each tag of each item in the cluster of items.

21. The system as defined in claim 20 wherein the items are clustered by being held in a common holding means.

22. The system as defined in claim 21 wherein the common holding means is movable by a transport means,

the tag reader is mounted on a transport means, and

the reading means is operable to read the associated item ID for each item in the threshold number of items while the common holding means holding the cluster of items is carried by the transport means.

23. The system as defined in claim 22 further comprising the step of tracking the location of the common holding means by determining the location of the transport means.

24. The system as defined in claim 23 wherein the transport means moves the common holding means within a storage space having a set of spaced location tags, each location tag being located at an associated location within the storage space and being operable to transmit location information to the tag reader on the transport means.