Blind People Interacting with Large Touch Surfaces: Strategies for One-handed and Two-handed Exploration

“Research has tried to improve these interfaces by leveraging gesture-based interaction, including understanding the preference and performance of both new and reference gestures [16], presenting new text-entry methods [12, 21] and browsing the interface using multitouch actions [15].”

“Research has tried to improve these interfaces by leveraging gesture-based interaction, including understanding the preference and performance of both new and reference gestures [16], presenting new text-entry methods [12, 21] and browsing the interface using multitouch actions [15].”

“Unlike Kane et al’s count task [17], each of our target instances had the same name and required the user to maintain awareness of the visited targets.”

“Research has tried to improve these interfaces by leveraging gesture-based interaction, including understanding the preference and performance of both new and reference gestures [16], presenting new text-entry methods [12, 21] and browsing the interface using multitouch actions [15].”

“interactions [13], we devised a two-hand alternative of Explore by Touch.”

“…solutions include the use of sonification to convey geometric information [31]; two-handed map exploration on tabletops with simultaneous audio feedback [10]; touchscreens with raised-line overlays [5]; and software overlays that ease the access to spatially structured elements in the map [12].”

“They could explore the map with both hands, as they are accustomed to [19], when they did not request any audio information.”

“However, interactive maps usually require larger devices and/or tactile overlays (Ducasse et al., 2018; Guerreiro et al., 2015; Kane et al., 2011) and most virtual navigation solutions require specialized equipment (Kreimeier and Götzelmann, 2019; Yatani et al., 2012; Zhao et al., 2018).”

“Blind people perform common activities either through direct exploration [20], text-entry [47], gesture-based [9], and multiple selections [64] on a smartphone.”

“apply the explore by touch approach to ’see’ their surroundings through their skilled touch perception capabilities [17, 29].”

“We have also aggregated shape and line exploration strategies observed across multiple experiments and found that users employed additional techniques including making crosses at vertex points to find connecting line segments (B) and scanning horizontally across the shape to uncover symmetry (C) [29, 72].”

“The blind people are using smartphones either through direct exploration (Guerreiro et al. 2015), text-entry (Oliveira et al. 2011), gesture-based (Buzzi et al. 2016), multiple selections, and braille-to-smartphone integration (Kane et al. 2008; Southern et al. 2012).”

“) to follow finger movement over a digital map, and render the content with auditory or vibrational feedback [2, 6, 5, 10, 25].”

“Researchers have drawn attention to the human–computer interaction (HCI) of touchscreen gestures of visually impaired people, including gesture performance and preferences [4, 25], the usability differences between onehanded gestures and two-handed gestures [14], and the development of new interactive gestures [6, 46].”

“…have investigated the exploration strategies for real and virtual tactile shapes and graphics in 2D (Rovira et al., 2011; Vinter et al., 2012; Bara, 2014; Guerreiro et al., 2015; Tennison and Gorlewicz, 2016; Bardot et al., 2017; Tekli et al., 2018; Bahrin et al., 2019; Vinter et al., 2020).”

“[18] observed various two-handed strategies including symmetrical hand movements when exploring the graphic.”

“In a different context, we supported two-handed exploration of large touch surfaces [Guerreiro et al. 2015a] using a similar approach.”

“in a more recent study on tabletop exploration by people with visual impairment [11].”

“In addition to further studies on the virtual cursors presented here, recorded data with this plug-in will be used to define web GUI design recommendations for alternative pointing devices such as a keyboard, to improve previous work on estimating the beginning of pointing trajectories [12], and to build a predictive…”

“Users were instructed to use both hands for research purposes because locating targets on a touchscreen with both hands is more efficient [32].”

“Others leverage touchscreen displays with audio-haptic feedback, enabling virtual previews on widely available smartphones [15, 23, 25, 35, 36, 38, 61, 67, 68, 92, 100, 107].”

“BLV individuals could employ non-technological mitigation strategies, such as seeking assistance from sighted people [59], organizing their environments to memorize object locations [13], or using touch exploration to navigate their surroundings [27, 74].”

“In addition, we coded whether the participant maintained an anchor hand on the exhibit during hovering, as prior work highlights the importance of anchoring [27, 68]: • An anchor hand remained in contact with the exhibit (Y) • No anchor hand; both hands lifted away (X) A sequence such as B–SY–”

“Other solutions try to combine 2D movements with audio feedback to simulate map exploration on tabletops [9], or use mobile applications to virtually discover an area through 3D audio [8], [10], [11].”

“This is supported by some studies on adult participants showing that blind individuals benefit more from using both hands during tactile exploration and size representation of familiar objects compared to sighted peers (Guerreiro et al. 2015; Morash et al. 2014; Smith et al. 2005).”

“For example, Guerreiro et al. mentioned several areas of improvement with new input and navigation techniques for visually impaired users (Guerreiro et al., 2015).”

“Users with blindness or low vision also employ the sides and corners of a device as spatial references (Guerreiro et al. 2015).”

“ce or via a separate wearable. Similar technologies have also been designed to support users for whom the visual channel is restricted or blocked (i.e., individuals who are blind and visuallyimpaired [7, 18, 19, 22, 27], with the aim of substituting or complementing visual feedback with other forms of accessible infor…”

“, individuals who are blind and visually-impaired [5], [13], [14], [17], [21]).”

“Blind people perform common activities either through direct exploration [18], text entry [19], gesture-based [20] and multi-touch interaction [21] on smartphones and smartwatches.”

“Blind people now can easily identify objects, navigate, read documents, and explore the environment [18], text entry [19] by using mobile phone applications.”

“An experimental study with blind subjects showed that it is time-consuming for blind people to locate the targets on a large touch surface (Guerreiro et al., 2015).”