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 Design and develop a VE system for users who are blind Conduct experiments on the usability of the VE system
BlindAid System - Conclusion Avoid overload processing Clear Back to simple Intuitive Based on previous knowledge
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– 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 In a complex VE the participants used mostly their own landmarks, and they usually installed two of their own.
BlindAid System - Conclusion Avoid overload processing Clear 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