Toward Non-visual Graphics Representations on Vibratory Touchscreens: Shape Exploration and Identification

Considerable advancements in vibratory and auditory feedback have transformed the touchscreen from a simple visual input/output device to one that is highly interactive and multimodal. While auditory feedback is useful in tasks where dictation is sufficient, it can be tedious and limited in tasks that require interpretation of graphics. In this work, we focus on exploration procedures, identification accuracy of graphics, and how repetition at smaller scales may help users identify similar graphics when only vibratory feedback is used on touchscreens. We conducted shape identification tasks with 56 blindfolded participants. Results suggest users are able to reliably identify basic 2D shapes within 90 s using only haptic feedback. Users were also able to identify smaller shapes with thin vibrating borders at rates comparable to their larger counterparts after being exposed to the larger shapes first. We also make observations on successful exploratory procedures employed and compare approaches among users. These findings serve to inform non-visual interface design using haptic feedback capabilities on touchscreens.