Paper Reading #29 : Usable Gestures for Blind People: Understanding Preference and Performance

Reference Information
Usable gestures for blind people: understanding preference and performance by Shaun K. Kane, Jacob O. Wobbrock, and Richard E. Ladner
 Published in the CHI '11 Proceedings of the 2011 annual conference on Human factors in computing systems.

Author Bios

• Shaun K. Kane is currently an Assistant Professor at the University of Maryland
• Jacob O. Wobbrock is currently an Associate Professor at the University of Washington.
• Richard E. Ladner is currently a Professor at the University of Washington

Summary

Hypothesis
That blind people have different wants from a touch based system than people with sight.
Methods 
1) 10 blind and 10 sighted participants were asked to take part in the first study that asked them to perform 2 possible gestures to perform a specific action that was read by a moderator. The gesture was performed and recorded on a Lenovo tablet PC and the participants were encouraged to explain their gesture as they performed it. After creating the gestures, participants were asked to rate the effectiveness of their gestures on a Likert scale.
2) The second study consisted of the same setup as the first and used the same participants only this time they were all asked to perform the same gestures for certain actions and rate them on a Likert scale.
 
Results
In the first test the researchers found that a blind person's gesture has more strokes than the sighted person. Also the blind people made more use of the edges in the tablet when positioning his/her gestures. Multi touch gestures were more occasionally used compared to the sight people as well. The second test saw very little difference in how easily the users recreated the gestures between the blind and the sighted. It was also seen that blind people made bigger overall gestures compared to the sighted people. It was also noted that blind users took much longer to perform the gestures and tended to be less straight.
 
Contents

Accessible touch screens still present challenges to both users and designers. Users must be able to learn new touch screen applications quickly and effectively, while designers must be able to implement accessible touch screen interaction techniques for a diverse range of devices and applications. Because most user interface designers are sighted, they may have a limited understanding of how blind people experience technology.Authors argue that accessible touch screen interfaces can be improved substantially if designers can better understand how blind people actually use touch screens.

The authors conduct two user studies that explore how blind and sighted people interact with touch screens and then presents design principles based on results.

 

Discussion
I thought the authors did a good job of doing what they set out to do. I think making touch based interfaces for blind people is a really cool thing to do.