FingerTalkie: Designing a Low-Cost Finger-Worn Device for Interactive Audio Labeling of Tactile Diagrams.

Traditional tactile diagrams for the visually-impaired (VI) use short Braille keys and annotations to provide additional information in separate Braille legend pages. Frequent navigation between the tactile diagram and the annex pages during the diagram exploration results in low efficiency in diagram comprehension. We present the design of FingerTalkie, a finger-worn device that uses discrete colors on a color-tagged tactile diagram for interactive audio labeling of the graphical elements. Through an iterative design process involving 8 VI users, we designed a unique offset point-and-click technique that enables the bimanual exploration of the diagrams without hindering the tactile perception of the fingertips. Unlike existing camera-based and finger-worn audio-tactile devices, FingerTalkie supports one-finger interaction and can work in any lighting conditions without calibration. We conducted a controlled experiment with 12 blind-folded sighted users to evaluate the usability of the device. Further, a focus-group interview with 8 VI users shows their appreciation for the FingerTalkie’s ease of use, support for two-hand exploration, and its potential in improving the efficiency of comprehending tactile diagrams by replacing Braille labels.