BlindAid: a Virtual
Exploration Tool for
People who are Blind
O. Lahav, Ph.D., D. Schloerb, Ph.D., S.
Kumar, and M. A. Srinivasan, Ph.D
Touch Lab, RLE, MIT
CT13, San Diego, June 2008
The Theory
Spatial cognitive map
Blinds’ exploration
Knowledge technology
The Theory
Blinds’ cognitive map
Spatial cognitive map
Blinds’ exploration
Knowledge technology
KT devices for spatial
cognitive mapping
O&M KT devices for blind
BlindAid System
2004 - present
(NEI - R21)
Research Aims
1.
Design and develop a VE system for users
who are blind
2.
Conduct experiments on the usability of the VE
system
BlindAid System - Conclusion
Clear
Avoid overload processing
Back to simple
Intuitive
Based on previous knowledge
The Learning Mode – User Interface
The Learning Mode – Researcher
Interface
Methodology – Participants
The study included four total blind participants
41-53 years old; one participant was congenitally
blind; one was female
Methodology – Research Instruments
Implementation Instruments:
Unknown simulated space (13 virtual environments)
Exploration task
Collection of the Data Instruments:
Observations
Usability questionnaire
Open interview
Modeling kit
Computer log
Research Studies
First study - Haptic properties
Second study - Audio properties
Third study - Exploration tools
First Study – Haptic Properties
Which haptic feedback properties used in the VE
strongly affected people who are blind?
The VE consisted of 20 objects of three types:
Different stiffness properties ‘S’ (soft-hard)
Different texture properties ‘T’ (smooth-rigid)
Different stiffness+texture properties ‘S+T’
First Study – Haptic Properties
Seven objects randomly chosen over six
VEs
First Study – Haptic Properties –
Result
All participants preferred objects with ‘S’ properties then
‘T’ or ‘S+T’ properties
All seven ‘S’ objects were listed as preferable
Participants preferred objects with ‘T’ properties only with
large height irrespective of the type of bump
First Study – Haptic Properties –
Result
All participants preferred a limited number of
feedbacks:
Different haptic feedbacks (wall,window, and door)
Hard objects and soft objects
Designation of area or objects with safety issues
Second Study - Audio Properties
Which audio feedback properties used in the VE
strongly affected people who are blind?
Audio type: mono, stereo, or stereo with rotation
Component’s description: short or long
Hearcon versa audio-labeled
Background sound
Second Study – Audio Properties
Six VEs
Second Study – Audio Properties –
Result
Three participants chose stereo.
Stereo helped them determine which direction to go
and provided more orientation to the overall space.
The stereo-rotation was an additional variable that
they needed to track.
They continually needed to imagine their orientation
at the time they heard the audio feedback.
Second Study – Audio Properties –
Result
The short component’s description and hearcon need
to be clear, recognizable, and short, without the need
to process it.
The ability to have background sound (e.g., street
noise) continuously with the stereo effect was
effective and needed.
The participants did not report feeling overloaded by
the audio effect or try to avoid interaction with the VE
components.
Third Study – Exploration Tools
What are the exploration tools that maximized the
participants’ exploration performance in the VE?
Move the VE workspace:
Using the arrow keys
Using the phantom button
Install and recall landmarks by:
User
Researcher
Zoom in - Zoom out (eliminate objects)
Third Study – Exploration Tools
Third Study – Exploration Tools –
Result
Each of the four participants chose to use the phantom
button:
Much more intuitive and a natural motion for the
participants
More immediately associated with the white cane
Sense of having control over movements
Did not have to take their hands off the Phantom
Able to drag the workspace at an angle
BlindAid System - Conclusion
Clear
Avoid overload processing
Back to simple
Intuitive and a natural
Based on previous knowledge
BlindAid System - Future
To Collect spatial information in advance (Mapquest)
Integrating the system in traditional O&M trainee
BlindAid System – Acknowledgments
The participants
NIH / NEI - R21
Jay Desloge
Carroll Center for the Blind