LOCATION INFORMATION BASED UPON ELECTRONIC TAGS

• US 20110273275A1
• Filed: 11/09/2009
• Published: 11/10/2011
• Est. Priority Date: 11/07/2008
• Status: Active Grant

• Current Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Original Assignee: Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno
• Inventors: Merriënboer, Simon Adrianus Van, Neef, Reinder Martinus, Ruizenaar, Marcel Gregorius Anthonius
• Granted Patent: US 8,779,897 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders

Abstract

A method of producing location information relating to articles (e.g. 9_o) utilizes tag devices (1₀, 1₁1₂, • • •)• The method comprises the steps of: • the tag devices (e.g. I₀), when in each other'"'"'s proximity, exchanging identification data and storing the time and date of the exchange together with the identification data of the other tag device, and also storing data relating to previous exchanges, • the tag devices, when in the proximity of an information collection device (e.g. 2_o), communicating the stored times and dates together with the stored identification data to an information collection device, • the information collection device (2₀) transmitting the times and dates and the identification data received from the tag devices to a central processing device (3), and • the central processing device (3) deriving location information from the times and dates and the identification data. Each tag device (e.g. 1_o), during each encounter with another tag device (e.g. 1₁), also exchanges and stores encounter data relating to previous encounters, such that the encounter data which each tag device communicates to an information collection device (e.g. 2_o) may relate to encounters of a plurality of tag devices.

Claims

1. A method of producing location information relating to articles (9₀, 9₁, . . . ) provided with tag devices (1₀, 1₁, . . . ), each tag device comprising a memory unit (11) for storing unique identification data (ID₀, ID₁, . . . ) associated with the respective tag device, a first communication unit (12) for communicating with other tag devices when in their proximity, and a clock unit (13), the method comprising the steps of:

a tag device (e.g. 1₀), during an encounter with another tag device (e.g. 1₁), exchanging identification data (ID₀, ID₁) and storing the time and date (e.g. T1, D1) of the exchange together with the identification data as encounter data (ED),

a tag device (e.g. 1₁), when in the proximity of an information collection device (e.g. 2₀) comprising a memory (21) and a second communication unit (23), communicating the stored encounter data (ED) to the information collection device,

the information collection device (2₀) communicating the encounter data (ED) received from tag devices to a processing device, and

the processing device (3) deriving location information from the encounter data (ED),

characterised in that each tag device (e.g. 1₀), during each encounter with another tag device (e.g. 1₁), also exchanges and stores encounter data (ED) relating to previous encounters, such that the encounter data (ED) which each tag device (e.g. 1₀) communicates to an information collection device (e.g. 2₀) may relate to encounters of a plurality of tag devices (1₀, 1₁, 1₂, . . . ).

2. The method according to claim 1, wherein each tag device (e.g. 1₀), during each encounter with another tag device (e.g. 1₁), exchanges all stored encounter data (ED) but stores only any new encounter data.

3. The method according to claim 1, wherein the information collection device (2) is constituted by a fixed station.

4. The method according to claim 1, wherein the information collection device (e.g. 2₀) is constituted by a dedicated tag device.

5. The method according to claim 1, wherein the information collection device (e.g. 2₀) transmits the encounter data (ED) in batches.

6. The method according to claim 1, wherein a tag device (e.g. 1₀) deletes stored encounter data (ED) once they have been communicated to an information collection device (e.g. 2₀).

7. The method according to claim 1, wherein an information collection device (e.g. 2₀) deletes stored encounter data once they have been communicated to a processing device (3).

8. The method according to claim 1, wherein the step of deriving location information comprises the following sub-steps:

using identification data (e.g. ID₀) to select encounter data (ED) relating to a particular tag device (e.g. 1₀),

using the times and dates of exchanges involving the same tag device to produce a set of possible locations at those times and dates,

using the same encounter data (ED) to identify the other tag devices involved in the exchanges represented by the encounter data, and

using any known start positions of the same and other tag devices to reduce the set of possible locations and to produce a most probable location at the times and dates.

9. The method according to claim 8, wherein the most probable location is determined for the earliest first time and date and is then used to determine the most probable location for the next time and date.

10. The method according to claim 1, wherein the step of deriving location information involves a Bayesian belief network.

11. The method according to claim 10, wherein the step of deriving location information comprises the sub-steps of:

defining, for each tag device (e.g. 1₀) and each point in time (T0, T1, . . . ), variables (Q0₀, Q0₁, . . . , Q1₀, Q1₁, . . . ) which represent the probabilities of the particular tag device being at a certain location at the particular point in time, and

updating said variables by using encounter data (ED).

12. A computer program product for carrying out the method according to claim 1.

20. A tag device (e.g. 1₀) for use in the method according to claim 1, the tag device comprising:

a memory unit (11) for storing identification data associated with the tag device,

a communication unit (12) for communicating with other tag devices, and

a clock unit (13),

the tag device being arranged for, when in the proximity of an information collection device (e.g. 2₀), communicating the stored encounter data (ED) to the information collection device,

characterised by being arranged for additionally exchanging and storing, during each encounter with another tag device (e.g. 1₁), encounter data (ED) relating to previous encounters, such that the encounter data (ED) which each tag device (e.g. 1₀) communicates to an information collection device (e.g. 2₀) may relate to encounters of a plurality of tag devices (1₀, 1₁, 1₂, . . . ).

21. An information collection device (e.g. 2₀) for use in the method according to claim 1, the information collection device (e.g. 2₀) comprising a memory (21), a first communication unit (22) and a second communication unit (23), and being arranged for receiving and storing encounter data (ED) from tag devices (1₀, 1₁, . . . ) and communicating the stored encounter data (ED) to a processing device (3).

22. A processing device (3) for use in the method according to claim 1, the processing device comprising a memory unit (31), a communication unit (33) and a processing unit (35) and being arranged for processing encounter data (ED) received from tag devices (1₀, 1₁, . . . ) and for deriving location data from the encounter data.

13. A system for producing location information relating to articles (e.g. 9₀), the system comprising:

tag devices (1₀, 1₁, 1₂ . . . ) comprising a memory unit (11) for storing unique identification data (ID) associated with the respective tag device, a first communication unit (12) for communicating with other tag devices, and a clock unit (13),

at least one information collection device (e.g. 2₀) comprising a memory (21) and a second communication unit (23), and

a processing device (3) comprising a memory unit (31) and a processing unit (35) for processing encounter data (ED) received from the tag devices (1₀, 1₁, 1₂, . . . ) and for deriving location data from the encounter data,

wherein the at least one information collection device (e.g. 2₀) is arranged for communicating the encounter data (ED) received from the tag devices to the processing device (3),

characterised in that each tag device (e.g. 1₀) is arranged for additionally exchanging and storing, during each encounter with another tag device (e.g. 1₁), encounter data (ED) relating to previous encounters, such that the encounter data (ED) which each tag device (e.g. 1₀) communicates to an information collection device (e.g. 2₀) may relate to encounters of a plurality of tag devices (1₀, 1₁, 1₂, . . . ).

14. The system according to claim 13, wherein each tag device (e.g. 1₀), during each encounter with another tag device (e.g. 1₁), exchanges all stored encounter data (ED) but stores only any new encounter data.

15. The system according to claim 13, wherein at least one information collection device (e.g. 2₀) is constituted by a fixed station.

16. The system according to claim 13, wherein the at least one information collection device (e.g. 2₀) is constituted by a dedicated tag device.

17. The system according to claim 13, wherein the processing device (3) is arranged for:

using identification data (e.g. ID₀) to select encounter data (ED) relating to a particular tag device (e.g. 1₀),

using the times and dates of exchanges involving the same tag device to produce a set of possible locations at those times and dates,

using the same encounter data (ED) to identify the other tag devices involved in the exchanges represented by the encounter data, and

using any known start positions of the same and other tag devices to reduce the set of possible locations and to produce a most probable location at the times and dates.

18. The system according to claim 13, wherein the step of deriving location information involves a Bayesian belief network.

19. The system according to claim 18, wherein the processing device (3) is arranged for:

defining, for each tag device (e.g. 1₀) and each point in time (T0, T1, . . . ), variables (Q0₀, Q0₁, . . . , Q1₀, Q1₁, . . . ) which represent the probabilities of the particular tag device being at a certain location at the particular point in time, and

updating said variables by using encounter data (ED).