Vulture: a mid-air word-gesture keyboard

TY - GEN

T1 - Vulture

T2 - The 32nd Conference on Human Factors in Computing Systems

AU - Markussen, Anders

AU - Jakobsen, Mikkel Rønne

AU - Hornbæk, Kasper

PY - 2014

Y1 - 2014

N2 - Word-gesture keyboards enable fast text entry by letting users draw the shape of a word on the input surface. Such keyboards have been used extensively for touch devices, but not in mid-air, even though their fluent gestural input seems well suited for this modality. We present Vulture, a word-gesture keyboard for mid-air operation. Vulture adapts touch based word-gesture algorithms to work in midair, projects users' movement onto the display, and uses pinch as a word delimiter. A first 10-session study suggests text-entry rates of 20.6 Words Per Minute (WPM) and finds hand-movement speed to be the primary predictor of WPM. A second study shows that with training on a few phrases, participants do 28.1 WPM, 59% of the text-entry rate of direct touch input. Participants' recall of trained gestures in mid-air was low, suggesting that visual feedback is important but also limits performance. Based on data from the studies, we discuss improvements to Vulture and some alternative designs for mid-air text entry.

AB - Word-gesture keyboards enable fast text entry by letting users draw the shape of a word on the input surface. Such keyboards have been used extensively for touch devices, but not in mid-air, even though their fluent gestural input seems well suited for this modality. We present Vulture, a word-gesture keyboard for mid-air operation. Vulture adapts touch based word-gesture algorithms to work in midair, projects users' movement onto the display, and uses pinch as a word delimiter. A first 10-session study suggests text-entry rates of 20.6 Words Per Minute (WPM) and finds hand-movement speed to be the primary predictor of WPM. A second study shows that with training on a few phrases, participants do 28.1 WPM, 59% of the text-entry rate of direct touch input. Participants' recall of trained gestures in mid-air was low, suggesting that visual feedback is important but also limits performance. Based on data from the studies, we discuss improvements to Vulture and some alternative designs for mid-air text entry.

KW - freehand interaction, in-air interaction, mid-air interaction, shape writing, text entry, word-gesture keyboard

U2 - 10.1145/2556288.2556964

DO - 10.1145/2556288.2556964

M3 - Article in proceedings

SN - 978-1-4503-2473-1

SP - 1073

EP - 1082

BT - Proceedings of the SIGCHI Conference on Human Factors in Computing Systems

PB - Association for Computing Machinery

Y2 - 26 April 2014 through 1 May 2014

ER -