The geta sandals a footprint location tracking system
This presentation is the property of its rightful owner.
Sponsored Links
1 / 22

The GETA Sandals: A Footprint Location Tracking System PowerPoint PPT Presentation


  • 106 Views
  • Uploaded on
  • Presentation posted in: General

The GETA Sandals: A Footprint Location Tracking System. Kenji Okuda, Shun-yuan Yeh , Chon-in Wu, Keng-hao Chang, and Hao-hua Chu National Taiwan University. What is GETA?. a kind of the traditional Japanese sandals. Outline. Motivation Related works Basic idea

Download Presentation

The GETA Sandals: A Footprint Location Tracking System

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


The geta sandals a footprint location tracking system

The GETA Sandals: A Footprint Location Tracking System

Kenji Okuda, Shun-yuan Yeh, Chon-in Wu, Keng-hao Chang, and Hao-hua Chu

National Taiwan University


What is geta

What is GETA?

  • a kind of the traditional Japanese sandals


Outline

Outline

  • Motivation

  • Related works

  • Basic idea

  • Design, implementation and evaluation

    • (three versions try and error)

  • Conclusion

  • Current works


Motivation

Motivation

  • Infrastructure cost (barriers for the user)

    (deployment, calibration, maintain)

    • Active Badge: IR receivers

    • Active BAT: Ultrasonic receivers + RF

    • Cricket: Ultrasonic beacons + RF

    • RADAR: WiFi network

    • Smart floor: pressure sensors

  • Goal

    • Infrastructure free

      (not succeed so far in this paper-> low infrastructure)

    • High accuracy


Related works

Related Works

  • Lee et al. proposed a method

    • by recognizing a sequence of incremental motions.

      • E.g. 5 steps north followed by 14 steps east.

    • Only can tell from place to place

      • e.g. living room, bedroom

  • Point research provides a vehicle self-tracking system


Basic idea of foot print approach

Basic idea of Foot-print Approach

( 180, 200 )

S5

S4

Sp

S3

S2

Sp=S1+S2+S3+S4+S5

S1

( 0, 0 )


How to sum up those vectors mathematically

(x2, y2)

θ

Coordinate system 2

(xc2, yc2)

(xc1, yc1)

Coordinate system 1

How to sum up those vectors mathematically

Coordinate system 1’

Need coordinate transformation for each left foot step.

(x1, y1)


Three try and error versions

Three try-and-error versions


Design version i

Ultrasonic Receivers

Ultrasonic Transmitters

Bottom view

side view

Design version I


Why using two transmitters

Can be rotated!!

d3

d4

d1

d2

Why using two transmitters

P2 (Unknown)

(fixed)

T1

fixed

P1 (known)


Why using two transmitters1

Why using two transmitters

Can Not be rotated any more !

P2 (determined)

T2

T1

P1 (known)


Problems of design i

Problems of Design I

  • Poor accuracy!

    • The interference of the signals from two transmitters.

      • Measures the incorrect vectors

      • Miss-detection of the user’s steps

      • All the calculations become failure.

  • Can not distinguish the user is moving forward or backward!


Design version ii

Orientation Sensor

Pressure sensor

Ultrasonic Transmitter

Ultrasonic Receivers

Bottom view

side view

Design version II


Design ii performance evaluation

Design II Performance Evaluation


Two main error sources

P1

Real path

Calculated path

Error Displacement

Two Main Error Sources

Fig1. Ultrasonic device err

Fig2. Orientation sensor err

θerr

P2

P1

Real path

Calculated path

Error Displacement

Error

P2

Steps


The solution of design ii

Passive RFID tag

The solution of design II

Adds a RFID reader in the GETA and put some tags in the environment.

Calculated Path of the user

Real Path of the user


Design version iii

Orientation Sensor

RFID Reader

Pressure Sensor

Ultrasonic Receivers board (with 2 Ultrasonic receivers)

Ultrasonic transmitter

Design version III


Hardware sensors of design iii

Hardware Sensors of Design III

  • Pressure sensors

    • Phidgets

  • Ultrasonic device

    • NAVINote (an electronic pen product)

    • Resolution : 0.2 mm

  • Orientation sensor

    • InterSense InterTrax2

    • Resolution : 0.02 degree

  • RFID Reader

    • SkyeTek M1

    • Read range: ~5cm


Design iii performance evaluation

The positioning error under different tag density over the walking distance.

Design III Performance Evaluation


Conclusion

Conclusion

  • A interesting self tracking method.

  • Low infrastructure cost.

  • The error of the orientation dominants our system accuracy.

  • Still have some limitations

    • E.g. climbing the stairs, walking crossover..


Current works

Current Works

  • Increase the accuracy

    (reducing the orientation error)

  • Solve the obstruction problem

  • Going down/up stair problem

  • Enhance the wearability (wireless)


Thank you

Thank you

Questions?

or send me E-mail

[email protected]

Thank you !


  • Login