“Did you see Bob?”: Human Localization using Mobile Phones Ionut Constandache

1. “Did you see Bob?”: Human Localization using Mobile Phones IonutConstandache Co-authors: XuanBao, Martin Azizyan, and Romit Roy Choudhury

2. Localization Technologies • Outdoor Driving directions  GPS, Skyhook • Indoor Localization in office  Cricket, Radar,BAT • Energy-Efficient Continuous localization  EnLoc, RAPS • Logical Context-aware ads  SurroundSense

3. Localization Technologies • Outdoor Driving directions  GPS, Skyhook • Indoor Localization in office  Cricket, Radar,BAT • Energy-Efficient Continuous localization  EnLoc, RAPS • Logical Context-aware ads  SurroundSense Human Localization: Guiding a user to finding another person

4. Usage Scenario Bob Alice

5. Usage Scenario Where is Bob? Please escort me to Bob. Bob Alice

6. Usage Scenario Where is Bob? Please escort me to Bob. Bob Alice

7. Usage Scenario Where is Bob? Please escort me to Bob. Bob Alice Provide an electronic Escortsystem.

8. Usage Scenario 20 steps North 5 steps East Bob N Alice’s Phone

9. Usage Scenario Alice’s Phone

10. Usage Scenario Bob Alice’s Phone

11. Human Localization • Finding Bob in unfamiliar place (E.g. library, mall, engineering building)

12. Human Localization • Finding Bob in unfamiliar place (E.g. library, mall, engineering building)

13. Human Localization • Finding Bob in unfamiliar place (E.g. library, mall, engineering building) • Better for Alice to be escorted to Bob

14. Human Localization • Finding Bob in unfamiliar place (E.g. library, mall, engineering building) • Better for Alice to be escorted to Bob Challenges: • Bob’s location unknown

15. Human Localization • Finding Bob in unfamiliar place (E.g. library, mall, engineering building) • Better for Alice to be escorted to Bob Challenges: • Bob’s location unknown Even if known still require … • WALK-able routes to Bob

16. Human Localization • Finding Bob in unfamiliar place (E.g. library, mall, engineering building) • Better for Alice to be escorted to Bob Challenges: • Bob’s location unknown Even if known still require … • WALK-able routes to Bob • Once in his vicinity, identify Bob

17. Can current localization schemes help?

18. Can current localization schemes help? too heavy on requirements … • Infrastructure: specialized hardware (e.g. Cricket, BAT, etc.) or • War-driving: build fingerprint DB (e.g. Radar, Skyhook, etc.)

19. Can current localization schemes help? too heavy on requirements … • Infrastructure: specialized hardware (e.g. Cricket, BAT, etc.) or • War-driving: build fingerprint DB (e.g. Radar, Skyhook, etc.) … need lightweight localization solution

20. Contents • Escort • Evaluation • Limitations and Future Work • Conclusion

21. Contents • Escort • Evaluation • Limitations and Future Work • Conclusion

22. Our Solution • Accelerometers/compasses track human movements • Standard sensors in mobile phones • Each user has a trail trail

23. Our Solution • Accelerometers/compasses track human movements • Standard sensors in mobile phones • Each user has a trail trail stepi, directioni > = TRAIL <

24. Our Solution • Accelerometers/compasses track human movements • Standard sensors in mobile phones • Each user has a trail trail

25. Our Solution • Deploy coordinate system to localize users • Any (fixed) location can be the origin • N, E directions are the Y, X axises E Origin N

26. Our Solution • Users join the coordinate system • When passing the origin • At encounters with users already in the system E (0,0) Origin N

27. Our Solution • Users join the coordinate system • When passing the origin • At encounters with users already in the system (x,y) E Origin N

28. Our Solution • Users join the coordinate system • When passing the origin • At encounters with users already in the system (x,y) (x,y) E Origin N

29. How does Escorting work?

30. How does Escorting work? C B A D

31. Escort Service Cloud A’s Trail C B A D

32. Escort Service Cloud A’s Trail C B A D

33. Escort Service Cloud C B A D

34. Escort Service Cloud C B A D

35. Escort Service Cloud C B IBC A IBD D IAC

36. Escort Service Cloud C B IBC A IBD D IAC

37. Trail Graph Escort Service Cloud B C IBC A IBD IAC D C B IBC A IBD D IAC

38. Trail Graph C B IBC IAC D A IBD

39. Escort along the Trail Graph C IAC D Bob Alice B A IBC IBD

40. Escort along the Trail Graph C IAC D Bob Alice B A IBC IBD

41. Escort along the Trail Graph C IAC D Bob Alice B A IBC IBD

42. Escort along the Trail Graph C IAC D Bob Alice Alice guided along user trails: Trails need to be accurate B A IBC IBD WALK-able routes

43. Challenges • Trails drift: acc. missed steps, compass biases t2 t1

44. Challenges • Trails drift: acc. missed steps, compass biases t2 t1

45. Challenges • Trails drift: acc. missed steps, compass biases t2 t1

46. Challenges • Trails drift: acc. missed steps, compass biases t2 t1

47. Challenges • Trails drift: acc. missed steps, compass biases t2 θ Compass bias t1

48. Challenges • Trails drift: acc. missed steps, compass biases t2 t1

49. Challenges • Trails drift: acc. missed steps, compass biases t2 t1

50. Challenges • Trails drift: acc. missed steps, compass biases t2 t1