Haptic Line Drawings for Blind Persons

Calle Sjöström, Henrik Danielsson, Charlotte Magnusson, Kirsten Rassmus-Gröhn
Presented at Vision 2002, Göteborg, Sweden, 21-25 July 2002


Certec has been working with touch-based interfaces - haptic interfaces - since 1995, exploring the possibilities they can offer people with different kinds of disabilities. A haptic interface transmits forces to your hand or fingers in a way that mimics the sensation of touching real objects. This makes it possible for a person to touch virtual objects, much like a sighted person can see objects or pictures on a computer screen.

The purpose of this study was to see if and how a haptic interface can be used to give blind persons access to line drawings and similar computer based graphics. User tests with 25 blind users from Sweden and Italy was carried out with the Phantom device from SensAble Technologies.

The tests included mathematical curves, haptic picture relieves and haptic floor plans.

The results were dependent upon both tasks and individual differences. Almost all users could feel and understand the mathematical curves. Approximately half of the users could identify the haptic picture relieves without contextual cues whereas more than 80% could identify parts of the drawing given that they were told what was depicted. More than 80% of the users could find a specific room in the floor plan. The users had quite different preferences for negative relief compared to positive relief, which can be compared with tactile maps that mostly are presented in positive relief.

The implications of this research could be new ways for blind persons to get access to graphical information, even on the internet.

Presentation slides (420 KB)