BlindAid: a Virtual Exploration Tool for
People who are Blind
O. Lahav, Ph.D., D. Schloerb, Ph.D., O. Lahav, Ph.D., D. Schloerb, Ph.D., S. Kumar, and M. A. Srinivasan, Ph.DS. Kumar, and M. A. Srinivasan, Ph.D
Touch Lab, RLE, MITTouch Lab, RLE, MIT
CT13, San Diego, June 2008CT13, San Diego, June 2008
The Theory
Blinds’ explorationSpatial cognitive map
Knowledge technology
Spatial cognitive map
The Theory
Blinds’ cognitive map
Blinds’ exploration
Knowledge technology
O&M KT devices for blindKT devices for spatialcognitive mapping
BlindAid System2004 - present (NEI - R21)NEI - R21)
Research AimsResearch 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
Back to simple
Clear
Based on previous knowledgeIntuitive
Avoid overload processing
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 propertiesSecond study - Audio propertiesThird 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’ propertiesAll seven ‘S’ objects were listed as preferableParticipants 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
Six VEs
Second Study – Audio Properties
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 buttonInstall and recall landmarks by: User ResearcherZoom 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 angleIn a complex VE the participants used mostly their own landmarks, and they usually installed two of their own.
BlindAid System - Conclusion
Back to simple
Clear
Based on previous knowledgeIntuitive and a natural
Avoid overload processing
BlindAid System - Future
To Collect spatial information in advance (Mapquest)
Integrating the system in traditional O&M trainee
BlindAid System – Acknowledgments
The participantsNIH / NEI - R21 Jay DeslogeCarroll Center for the Blind