Keep in Touch: Combining Touch Interaction with Thumb-to-Finger µGestures for People with Visual Impairment
In 24th ACM International Conference on Multimodal Interaction (ICMI 2022). pages 105–116. 2022.
Gauthier Faisandaz, Alix Goguey, Christophe Jouffrais, Laurence Nigay
Résumé
We present a set of 8 thumb-to-finger microgestures (TTF μGestures) that can be used as an additional modality to enrich touch interaction in eyes-free situations. TTF μGestures possess characteristics especially suited for people with visual impairment (PVI). They have never been studied specifically for PVI to improve accessibility of touchscreen devices. We studied a set of 33 common TTF μGestures to determine which are feasible and usable without seeing while the index is touching a surface. We found that the constrained position of the hand and the absence of vision prevent participants from being able to efficiently target a specific phalanx. Thus, we propose a set of 8 TTF μGestures (6 taps, 2 swipes) balancing resiliency (i.e., low error-rate) and expressivity (i.e., number of possible inputs): as a dimension combined with the touch modality, it would realistically multiply the touch command space by eight. Within our set of 8 TTF μGestures, we chose a subset of 4 μGestures (2 taps and 2 swipes) and implemented an exploration scenario of an audio-tactile map with a raised-line overlay on a touchscreen and tested it with 7 PVI. Their feedback was positive on the potential benefits of TTF μGestures in enhancing the touch modality and supporting PVI interaction with touchscreen devices