The idea that leverages RFID labels for location determination and direction guidance

1. The idea that leverages RFID labels for location determination and direction guidance Suk chan Kang

2. Outline • Motivation • Why RFID for this idea? • Components • Feature • Prototype Trinetra System • RFID Shelf/Rack Label for location determination • RFID Label orientation and its direction coordinate • The guidance from different source • The absolute and local direction coordinate • Sample RFID deployment file format • Procedure for the direction guidance (1-6) • Toy simulator (1-2) • Toy simulator simulation procedure(1-6) • Conclusion

3. Go straight by 10 walks. Turn to the right. Go straight by 15 walks. Turn to the left. Go straight by 10 walks. Dig it !! Motivation • Impressed by guidance style of old treasure map • Cost-effective, convenient direction guidance for the destination • Better independence for the user, without bothering the store clerks • Synergy effect when used with other devices like bar code reader to discriminate between different products

4. Why RFID for this idea? • Relatively higher cost than that of bar-code • Baracoda’s IDBlue RFID-scanning pen has only 4cm-long reading distance ! • However • Basic, cheap RFID tag does suffice for this idea • No requirement of line-of-sight reading of the tags

5. Components • RFID label deployment data file indigenous for each store • Item database of the store that matches the items and their RFID shelf label • Smart phone • Passive RFID label • Passive RFID reader • Micro phone • Bluetooth headset • Speech-to-text software to issue the commands • Text-to-speech software to inform the user of the resulting messages

6. Feature • RFID-based aisle and shelf-level guidance and identification • Immunity for re-stocking and relocation • Most information is in the file to be stored in smart phone • Only needs to reconfigure the matching between items and their position(in the form of RFID number) in deployment file whenever the store updates its item data base • Can guide the user again even if the user happens to deviate from the desired routing

7. Prototype Trinetra System

8. RFID Shelf/Rack Label for location determination RFID Shelf/Rack Label for location determination

9. 9 12 6 12 9 3 3 6 RFID Label orientation and its direction coordinate • Every RFID Label is intuitively assigned its own indigenous local orientation in 12 division format • The direction coordinate of 12 division of a RFID label varies RFID by RFID • The direction which points at 12 o’clock is the direction of the side that RFID label faces

10. 9 6 12 3 3 12 6 9 The guidance from different source The same destination, different direction guidance, depending on the user’s position Rack destination Go to the 11 o’clock direction ! Go to the 4 o’clock direction ! View from the ceiling

11. 12 (North) 9 3 6 (South) 9 6 12 3 The absolute and local direction coordinate • The smart phone software should know the relation between the absolute coordinate and the local coordinate • This information is specified in RFID deployment file as the item “fdir” Absolute 12 division coordinate Local 12 division coordinate In this example, the local 12 o’clock points 3 o’clock direction in absolute coordinate

12. Sample RFID deployment file format #sNode x y fdir attri Enb Wnb Snb Nnb [sNode begin] sNode0 100 100 3 Norm 1 -1 15 -1 sNode1 150 100 6 Norm 2 0 16 -1 sNode2 200 100 9 Hole 3 1 17 -1 sNode3 250 100 3 Norm 4 2 18 -1 ………. sNode75 100 350 3 Norm 76 -1 90 60 sNode76 150 350 12 Norm 77 75 91 61 sNode77 200 350 9 Norm 78 76 92 62 [sNode end] *Fdir: The orientation that this RFID tag’s 12 o’clock faces, in absolute direction coordination *Attri: Attribute. Hole or Normal *Enb: East neighbor RFID tag id number -1 means no neighbor in that direction *Wnb: West neighbor RFID tag id number -1 means no neighbor in that direction *Snb: South neighbor RFID tag id number -1 means no neighbor in that direction *Nnb: North neighbor RFID tag id number -1 means no neighbor in that direction

13. Procedure for the direction guidance (1) • 1. Check and download a up to the date RFID label deployment file for a shop when entering the shop Brand new RFID deployment file

14. “RFID 100” Procedure for the direction guidance (2) • 2. Search for the item over the item data base of the store and get the RFID number of the destination where the items are waiting for the user • The user can use speech to text software for conveniently issue the command to smart phone “Orange juice”

15. Procedure for the direction guidance (3) • 3. Set the RFID taken in procedure 2 to the destination “Set destination 100”

16. Procedure for the direction guidance (4) • 4. Identify where the user is now, by reading the nearest RFID label around the user “RFID 9 is now set to your position”

17. Procedure for the direction guidance (5) • 5. Let the smart phone tell the user the routing • The software in the smart phone will use “shortest path algorithm” such as that of dijkstra • The smart phone will guide you to the destination in piece wise manner • The direction would be of 12 division format • The distance would be of the multiple of unit distance such as “5 walks” or “10 hops” “Tell me the rouging” “Turn to the 7 o’clock” “Go straight by 10 walks” “Turn …”

18. Procedure for the direction guidance (6) • 6. Iterate 4 to 5 until the user gets to the destination successfully • Even If the user would ever deviates, it is alright because the smart phone will suggest a new shortest path from where the user is now, to the destination

19. Toy simulator (1) • Simulates the previous procedure from (3) to (6) • Written in C++ by using Qt 3.3.4 library on Linux Platform • Uses Dijkstra’s shortest path algorithm • You can see the demo “avi” format file and source file at this address: (please click!) • You can compile it on Linux or Cygwin by typing: • >make clean; • >qmake; • >make clean; • Please just invoke “./rfidguidance &”

20. Toy simulator (2) Speech to text input Text to speech output User RFID label Routing line Rack Destination Routing hop list Local direction clock Absolute direction clock

21. Toy simulator simulation procedure(1) Node 0 Node 85 (not shown) Text to speech output message tells: “Node 85 is now destination” Speech to text input commanded: “set destination 85”

22. Toy simulator simulation procedure(2) “Go to the 9’oclock direction by 8 hops” Absolute direction clock always points at the absolute 12’oclock (It does not move) The short hand points at the side this RFIDlabel faces The direction for guidance routing at this label is 9 o’clock when compared with the short hand

23. Toy simulator simulation procedure(3) “Go to the 9’oclock direction by 2 hops” Node 85 When the user seems to have deviated, the user has only to tell “show routing” again

24. Toy simulator simulation procedure(4) “Go to the 3’oclock direction by 5 hops”

25. Toy simulator simulation procedure(5) “Go to the 0’oclock direction by 1 hops” The direction for guidance routing at this label (84)and the side this label faces are the same

26. Toy simulator simulation procedure(6) “You have already reached your destination !!”

27. Conclusion • RFID label based location determination and direction guidance • Better degree of freedom for the user, not disturbing the store clerk • Relatively robust for physical re-stocking and relocation