Effects of Continuous Auditory Feedback on Drawing Trajectory-Based Finger Gestures

Abstract

The well-known “fat finger” issue limits the interaction performance of trajectory-based finger gestures. To alleviate this issue, this work focuses on the possibility of using additional continuous auditory feedback to assist trajectory-based finger gestures. First, the experiment validated that, with the visual feedback only, the bare fingertip led to more errors in drawing of intersectional points, endpoints of closed gestures, and gestural length and shape variability compared to when the finger-attached pen was used. Then, we designed different types of auditory feedback (discrete beep, static, gradual) to provide additional information on the spatial relationship between finger-contact point and the endpoints or intersections of predefined gestures. An experiment that evaluates the effects of individual or combination of designed auditory feedback on trajectory-based finger gestures was conducted. These results show a few differences between them. However, a combination of gradual (amplitude and frequency) continuous sound and beep reached the highest drawing accuracy for trajectory-based finger gestures, which is similar to that of a finger-attached pen. This research offers insights and implications for the future design of continuous auditory feedback on small touchscreens.