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Electrovibration has been used extensively with touchscreens and other rigid objects. We propose extending electrovibration to wearables such as wristbands, jewelry and clothing, and present an exploration of the resulting design space and preliminary experimentation with haptic prototypes made of flexible materials and conductive textiles.

We describe the graduate-level CanHap 501 (wiki.canhaptics.ca) course, an introduction to the inception, creation and evaluation of haptic and multimodal human-computer interfaces. The course covers perceptual and attentional foundations, and emphasizes control and/or display of computed sensations and environments through haptic devices to users’ sense of touch for the purpose of haptic communication—e.g., signalling, social and affective touch, and sharing of control between humans and smart systems.

This paper describes the design, construction, and initial evaluation of a handheld information device that supports combined tactile and graphical interaction. The design comprises a liquid crystal graphic display co-located with a miniature, low-power, distributed tactile transducer. This transducer can create electronically-controlled lateral skin deformation patterns which give the sensation of sliding over small shapes. It is integrated within a slider mechanism to control scrolling. It also functions as a detent when pushing on it. Tactile feedback and the combination of visual and tactile feedback in a mobile context enable the development of new functions, such as multimodal navigation within large graphic spaces

When a progressive wave of localized deformations occurs tangentially on the fingerpad skin, one typically experiences the illusion of a small object sliding on it. This effect was investigated because of its potential application to the display of Braille. A device was constructed that could produce such deformation patterns along a line. Blind subjects' ability to read truncated Braille characters (‘○○’, ‘○•’, ‘•○’, and ‘••’) using the device was experimentally tested and compared to their performance with a conventional Braille medium. While subjects could identify two-character strings with a high rate of success, several factors need to be addressed before a display based on this principle can become practical.

Scrolling interactions are an important aspect of the design of usable touchscreen interfaces, particularly for handheld devices that can only display a limited amount of information at once. Using a touchscreen capable of dynamically altering its surface friction, we explore the design space of haptically-augmented scrolling interactions and investigate programmable friction's ability to provide appropriate feedback in envisioned usage scenarios. We performed five user experiments to evaluate respectively the identifiability of a set of iconic detents, the countability of detents, the perception of detent density, the synchronization of tactile feedback to on-screen events, and the optimal friction pattern for a spring-like resistance. The results of these experiments provide valuable information that will inform the design of scrolling interactions that leverage programmable friction for an improved user experience.

Touch interactions have refreshed some of the 'glowing enthusiasm' of thirty years ago for direct manipulation interfaces. However, today's touch technologies, whose interactions are supported by graphics, sounds or crude clicks, have a tactile sameness and gaps in usability. We use a Large Area Tactile Pattern Display (LATPaD) to examine design possibilities and outcomes when touch interactions are enhanced with variable surface friction. In a series of four studies, we first confirm that variable friction gives significant performance advantages in low-level targeting activities. We then explore the design space of variable friction interface controls and assess user reactions. Most importantly, we demonstrate that variable friction can have a positive impact on the enjoyment, engagement and sense of realism experienced by users of touch interfaces.

Rich tactile interaction with control surfaces has been compromised in the transition to touch interfaces. This paper discusses new haptic effects that restore physicality to touch interaction by dynamically altering a touchscreen's frictional properties.

Raised line patterns are used extensively in the design of tactile graphics for persons with visual impairments. A tactile stroke pattern was therefore developed to enable the rendering of vector graphics by lateral skin deformation. The stroke pattern defines a transversal profile and a longitudinal texture which provide tactile feedback while respectively crossing over the stroke and tracing its length. The stroke pattern is demonstrated with the rendering of lines, circles and polygons, and is extensible to other vector graphics primitives such as curves. The parametric nature of the stroke allows the representation of distinctive line types and the online adjustment of line thickness and other parameters according to user preferences and capabilities. The stroke pattern was informally evaluated with four visually impaired volunteers.

This paper presents preliminary work towards the development and evaluation of a practical refreshable tactile graphics system for the display of tactile maps, diagrams and graphs for people with visual impairments. Refreshable tactile graphics were dynamically produced by laterally deforming the skin of a finger using the STReSS2 tactile display. Tactile features were displayed over an 11x6 cm virtual surface by controlling the tactile sensations produced by the fingerpad-sized tactile display as it was moved on a planar carrier. Three tactile rendering methods were used to respectively produce virtual gratings, dots and vibrating patterns. These tactile features were used alone or in combination to display shapes and textures. The ability of the system to produce tactile graphics elements was evaluated in five experiments, each conducted with 10 sighted subjects. The first four evaluated the perception of simple shapes, grating orientations, and grating spatial frequencies. The fifth experiment combined these elements and showed that tactile icons composed of both vibrating contours and grated textures can be identified. The fifth experiment was repeated with 6 visually impaired subjects with results suggesting that similar performance should be expected from that user group.

Earlier work with a 1D tactile transducer demonstrated that lateral skin deformation is sufficient to produce sensations similar to those felt when brushing a finger against a line of Braille dots. Here, we extend this work to the display of complete 6-dot Braille characters using a general purpose 2D tactile transducer called STReSS2. The legibility of the produced Braille was evaluated by asking seven expert Braille readers to identify meaningless 5-letter strings as well as familiar words. Results indicate that reading was difficult but possible for most individuals. The superposition of texture to the sensation of a dot improved performance. The results contain much information to guide the design of a specialized Braille display operating by lateral skin deformation. They also suggest that rendering for contrast rather than realism may facilitate Braille reading when using a weak tactile transducer

A computer implementation of a classic memory card game was adapted to rely on touch rather than vision. Instead of memorizing pictures on cards, players explore tactile graphics on a computer-generated virtual surface. Tactile sensations are created by controlling dynamic, distributed lateral strain patterns on a fingerpad in contact with a tactile display called STRESS2. The tactile graphics are explored by moving the device within the workspace of a 2D planar carrier. Three tactile rendering methods were developed and used to create distinct tactile memory cards. The haptic memory game showcases the capabilities of this novel tactile display technology.