BrailleSketch: A Gesture-based Text Entry Method for People with Visual Impairments

Abstract

In this paper, we present BrailleSketch, a gesture-based text input method on touchscreen smartphones for people with visual impairments. To input a letter with BrailleSketch, a user simply sketches a gesture that passes through all dots in the corresponding Braille code for that letter. BrailleSketch allows users to place their fingers anywhere on the screen to begin a gesture and draw the Braille code in many ways. To encourage users to type faster, BrailleSketch does not provide immediate letter-level audio feedback but instead provides word-level audio feedback. It uses an auto-correction algorithm to correct typing errors. Our evaluation of the method with ten participants with visual impairments who each completed five typing sessions shows that BrailleSketch supports a text entry speed of 14.53 word per min (wpm) with 10.6% error. Moreover, our data suggests that the speed had not begun to plateau yet by the last typing session and can continue to improve. Our evaluation also demonstrates the positive effect of the reduced audio feedback and the auto-correction algorithm.