Laterotactile Rendering of Vector Graphics with the Stroke Pattern

Abstract. 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. Key words: assistive technology, visual impairment, tactile graphics, tactile display, haptic rendering, laterotactile renderin

Interactive audio-tactile maps for visually impaired people

International audienceVisually impaired people face important challenges related to orientation and mobility. Indeed, 56% of visually impaired people in France declared having problems concerning autonomous mobility. These problems often mean that visually impaired people travel less, which influences their personal and professional life and can lead to exclusion from society. Therefore this issue presents a social challenge as well as an important research area. Accessible geographic maps are helpful for acquiring knowledge about a city's or neighborhood's configuration, as well as selecting a route to reach a destination. Traditionally, raised-line paper maps with braille text have been used. These maps have proved to be efficient for the acquisition of spatial knowledge by visually impaired people. Yet, these maps possess significant limitations. For instance, due to the specificities of the tactile sense only a limited amount of information can be displayed on a single map, which dramatically increases the number of maps that are needed. For the same reason, it is difficult to represent specific information such as distances. Finally, braille labels are used for textual descriptions but only a small percentage of the visually impaired population reads braille. In France 15% of blind people are braille readers and only 10% can read and write. In the United States, fewer than 10% of the legally blind people are braille readers and only 10% of blind children actually learn braille. Recent technological advances have enabled the design of interactive maps with the aim to overcome these limitations. Indeed, interactive maps have the potential to provide a broad spectrum of the population with spatial knowledge, irrespective of age, impairment, skill level, or other factors. To this regard, they might be an efficient means for providing visually impaired people with access to geospatial information. In this paper we give an overview of our research on making geographic maps accessible to visually impaired people

Towards the creation of a tactile version of the Self-Assessment Manikin (T-SAM) for the emotional assessment of visually impaired people

The Self-Assessment Manikin (SAM) is one of the most extensively used instruments in the situational assessment of the emotional state in experimental or clinical contexts of emotional induction. However, there is no instrument of this kind adapted for blind or visually impaired people. In this paper, we present the results of the preliminary validation of a tactile adaptation of the SAM, the Tactile Self-Assessment Manikin (T-SAM). For this purpose, 5 people with visual disabilities participated in a focus group in which the usability of this adaptation was evaluated, as well as its usefulness in representing the valence and arousal subscales of the original instrument. The analysis of the content of this focus group suggests a pertinent content validity, while the participants correctly understood both the purpose of the instrument, and the tactile representations of valence and activation constructs created by the research team. However, the difficulty of blind people from birth to understand the graphic representation of an emotional facial expression was detected, which represents a limitation to control in future steps in the validation of T-SAM

Visual-Tactile Image Representation For The Visually Impaired Using Braille Device

Nowadays Internet usage is dramatically increasing all over the world and the information dissemination and acquisition is easier for sighted users. Unfortunately, visually impaired are still facing difficulties in interaction with websites. Particularly, screen reader is unable to facilitate disabled users to identify images such as basic geometric shapes. Inability to identify the shapes displayed on the screen creates restriction to interact and comprehend the content of websites for visually impaired. Thus, this project examines earlier researches and eases the web interaction of the blind people by identifying the shape of visual image converted into tactile representation using Braille device. For further investigation of the hypotheses, qualitative and quantitative method is used. The study findings are addressed to build a system that tackles the issue that screen reader is unable to address. System evaluation is executed upon producing the prototype of the system which comprises of user testing. The system is expected to improve understanding the content of webpage and enhance the interaction of visually impaired with web. Future recommendations and further findings will be discussed when system prototype milestone is fulfilled

Touch-Screen Technology for the Dynamic Display of 2D Spatial Information Without Vision: Promise and Progress

Many developers wish to capitalize on touch-screen technology for developing aids for the blind, particularly by incorporating vibrotactile stimulation to convey patterns on their surfaces, which otherwise are featureless. Our belief is that they will need to take into account basic research on haptic perception in designing these graphics interfaces. We point out constraints and limitations in haptic processing that affect the use of these devices. We also suggest ways to use sound to augment basic information from touch, and we include evaluation data from users of a touch-screen device with vibrotactile and auditory feedback that we have been developing, called a vibro-audio interface

Analysis of Product Architectures of Pin Array Technologies for Tactile Displays

Refreshable tactile displays based on pin array technologies have a significant impact on the education of children with visual impairments, but they are prohibitively expensive. To better understand their design and the reason for the high cost, we created a database and analyzed the product architectures of 67 unique pin array technologies from literature and patents. We qualitatively coded their functional elements and analyzed the physical parts that execute the functions. Our findings highlight that pin array surfaces aim to achieve three key functions, i.e., raise and lower pins, lock pins, and create a large array. We also contribute a concise morphological chart that organises the various mechanisms for these three functions. Based on this, we discuss the reasons for the high cost and complexity of these surface haptic technologies and infer why larger displays and more affordable devices are not available. Our findings can be used to design new mechanisms for more affordable and scalable pin array display systems

Designing a New Tactile Display Technology and its Disability Interactions

People with visual impairments have a strong desire for a refreshable tactile interface that can provide immediate access to full page of Braille and tactile graphics. Regrettably, existing devices come at a considerable expense and remain out of reach for many. The exorbitant costs associated with current tactile displays stem from their intricate design and the multitude of components needed for their construction. This underscores the pressing need for technological innovation that can enhance tactile displays, making them more accessible and available to individuals with visual impairments. This research thesis delves into the development of a novel tactile display technology known as Tacilia. This technology's necessity and prerequisites are informed by in-depth qualitative engagements with students who have visual impairments, alongside a systematic analysis of the prevailing architectures underpinning existing tactile display technologies. The evolution of Tacilia unfolds through iterative processes encompassing conceptualisation, prototyping, and evaluation. With Tacilia, three distinct products and interactive experiences are explored, empowering individuals to manually draw tactile graphics, generate digitally designed media through printing, and display these creations on a dynamic pin array display. This innovation underscores Tacilia's capability to streamline the creation of refreshable tactile displays, rendering them more fitting, usable, and economically viable for people with visual impairments

Making Graphical Information Accessible Without Vision Using Touch-based Devices

Accessing graphical material such as graphs, figures, maps, and images is a major challenge for blind and visually impaired people. The traditional approaches that have addressed this issue have been plagued with various shortcomings (such as use of unintuitive sensory translation rules, prohibitive costs and limited portability), all hindering progress in reaching the blind and visually-impaired users. This thesis addresses aspects of these shortcomings, by designing and experimentally evaluating an intuitive approach —called a vibro-audio interface— for non-visual access to graphical material. The approach is based on commercially available touch-based devices (such as smartphones and tablets) where hand and finger movements over the display provide position and orientation cues by synchronously triggering vibration patterns, speech output and auditory cues, whenever an on-screen visual element is touched. Three human behavioral studies (Exp 1, 2, and 3) assessed usability of the vibro-audio interface by investigating whether its use leads to development of an accurate spatial representation of the graphical information being conveyed. Results demonstrated efficacy of the interface and importantly, showed that performance was functionally equivalent with that found using traditional hardcopy tactile graphics, which are the gold standard of non-visual graphical learning. One limitation of this approach is the limited screen real estate of commercial touch-screen devices. This means large and deep format graphics (e.g., maps) will not fit within the screen. Panning and zooming operations are traditional techniques to deal with this challenge but, performing these operations without vision (i.e., using touch) represents several computational challenges relating both to cognitive constraints of the user and technological constraints of the interface. To address these issues, two human behavioral experiments were conducted, that assessed the influence of panning (Exp 4) and zooming (Exp 5) operations in non-visual learning of graphical material and its related human factors. Results from experiments 4 and 5 indicated that the incorporation of panning and zooming operations enhances the non-visual learning process and leads to development of more accurate spatial representation. Together, this thesis demonstrates that the proposed approach —using a vibro-audio interface— is a viable multimodal solution for presenting dynamic graphical information to blind and visually-impaired persons and supporting development of accurate spatial representations of otherwise inaccessible graphical materials

Haptics: state of the art survey

This paper presents a novel approach to the understanding of Haptic and its related fields where haptics is used extensively like in display systems, communication, different types of haptic devices, and interconnection of haptic displays where virtual environment should feel like equivalent physical systems. There have been escalating research interests on areas relating to haptic modality in recent years, towards multiple fields. However, there seems to be limited studies in determining the various subfields and interfacing and related information on haptic user interfaces and its influence on the fields mentioned. This paper aims to bring forth the theory behind the essence of Haptics and its Subfields like haptic interfaces and its applications

Tactile audio responsive intelligent system

For people with visual impairments, information encoded in a visual format creates certain barriers. To alleviate this, a large volume of research has been conducted in the field of assistive technology. In our work, we developed a special system that makes educational materials more accessible. The system consists of three components: the pre-labelled tactile graphics, an interactive labelling web tool and the phone application. Tactile graphics are used at schools for the blind and allow the students to understand non-textual information by touch. The digital version of the graphics first needs to be labelled by teachers using the developed web tool. Then, the phone app, which is based on the Android platform, will accompany those graphics with the audio descriptions. The fundamental purpose of the developed app is to allow the user to gain information without sighted assistance. We also conducted a study to evaluate the system. First, the structured interview was carried out to gather data about the participant’s experience with the tactile graphics and mobile devices. Next, quantitative measurements were obtained through a series of experiments. Subsequently, a post-experimental session was carried out to record the participants’ thoughts and opinions about the system. The results of the experiments demonstrated that the proposed mobile application allows the users to explore the graphics more efficiently