Visually-impaired Users Research Articles

CHALLENGES FOR BLIND AND VISION IMPAIRED USERS OF A VISUAL QUESTION ANSWERING TOOL: IMPLICATIONS FOR AGING ADULTS

Recent technological developments provide individuals with vision impairment the transformative ability to upload pictures they take and promptly receive descriptions from remote workers. This study aimed to: identify challenges for visually impaired individuals to use such technology to obtain health-related information and provide recommendations for crowd-workers and the future development of assistive artificial intelligence (AI) design. In spring and summer of 2019, we analyzed 265 images of medication packages submitted by users of a visual question answering (VQA) application called VizWiz -- a smartphone application that provides near realtime assistance to visually impaired users by employing crowd-workers. We developed a 4-category coding scheme to analyze image quality, with two independent coders achieving excellent intercoder reliability (85%-95%). Of the 265 images, we found less than half were legible (46%), contained clear indicators for information sought (40%), or had minimum background noise (40%); while only a small percentage contained complete information (6%). Through thematic analysis of the data, we also highlight seven challenges with queries submitted by vision impaired users . Based on our findings, we make recommendations for the future design of VQA technologies, such as VizWiz, for visually impaired users. We also suggest that there is both great need and potential for user-centered design research to significantly enhance such assistive technologies. While this study did not focus exclusively on data submitted by aging adults, many VizWiz users are, in fact, aging adults, and such assistive technologies have strong implications for the design of assistive technology for this age group.

Am I missing something?

People with a visual impairment are more likely to experience social isolation as an effect of their vision loss. Social media can particularly benefit these users, but it is of concern if it cannot be fully and successfully used. This study was instigated at the request of an advisory group of visual impaired users and experts. The aim of the study was to investigate potential accessibility issues visually impaired users could encounter when using social media. A major concern was over missing content embedded in images on social media sites. A subsequent evaluation of Facebook posts carried out by a group of student participants demonstrated that nearly half of images considered contained embedded text, which would be inaccessible to visually impaired users. Despite efforts by social media companies to improve accessibility, any text present in images is not presented in an accessible way to visually impaired users. This research demonstrated the inequality that can arise from partial accessibility and the requirement to consider accessibility at all stages of design and development.

Testing a Shape-Changing Haptic Navigation Device With Vision-Impaired and Sighted Audiences in an Immersive Theater Setting

Flatland was an immersive “in-the-wild” experimental theater and technology project, undertaken with the goal of developing systems that could assist “real-world” pedestrian navigation for both vision-impaired (VI) and sighted individuals, while also exploring inclusive and equivalent cultural experiences for VI and sighted audiences. A novel shape-changing handheld haptic navigation device, the “Animotus,” was developed. The device has the ability to modify its form in the user's grasp to communicate heading and proximity to navigational targets. Flatland provided a unique opportunity to comparatively study the use of novel navigation devices with a large group of individuals (79 sighted, 15 VI) who were primarily attending a theater production rather than an experimental study. In this paper, we present our findings on comparing the navigation performance (measured in terms of efficiency, average pace, and time facing targets) and opinions of VI and sighted users of the Animotus as they negotiated the 112 m2 production environment. Differences in navigation performance were nonsignificant across VI and sighted individuals and a similar range of opinions on device function and engagement spanned both groups. We believe more structured device familiarization, particularly for VI users, could improve performance and incorrect technology expectations (such as obstacle avoidance capability), which influenced overall opinion. This paper is intended to aid the development of future inclusive technologies and cultural experiences.

Ticker: An Adaptive Single-Switch Text Entry Method for Visually Impaired Users.

Ticker is a probabilistic stereophonic single-switch text entry method for visually-impaired users with motor disabilities who rely on single-switch scanning systems to communicate. Such scanning systems are sensitive to a variety of noise sources, which are inevitably introduced in practical use of single-switch systems. Ticker uses a novel interaction model based on stereophonic sound coupled with statistical models for robust inference of the user's intended text in the presence of noise. As a consequence of its design, Ticker is resilient to noise and therefore a practical solution for single-switch scanning systems. Ticker's performance is validated using a combination of simulations and empirical user studies.

Unifying Terrain Awareness for the Visually Impaired through Real-Time Semantic Segmentation.

Navigational assistance aims to help visually-impaired people to ambulate the environment safely and independently. This topic becomes challenging as it requires detecting a wide variety of scenes to provide higher level assistive awareness. Vision-based technologies with monocular detectors or depth sensors have sprung up within several years of research. These separate approaches have achieved remarkable results with relatively low processing time and have improved the mobility of impaired people to a large extent. However, running all detectors jointly increases the latency and burdens the computational resources. In this paper, we put forward seizing pixel-wise semantic segmentation to cover navigation-related perception needs in a unified way. This is critical not only for the terrain awareness regarding traversable areas, sidewalks, stairs and water hazards, but also for the avoidance of short-range obstacles, fast-approaching pedestrians and vehicles. The core of our unification proposal is a deep architecture, aimed at attaining efficient semantic understanding. We have integrated the approach in a wearable navigation system by incorporating robust depth segmentation. A comprehensive set of experiments prove the qualified accuracy over state-of-the-art methods while maintaining real-time speed. We also present a closed-loop field test involving real visually-impaired users, demonstrating the effectivity and versatility of the assistive framework.

A Highly Accurate and Reliable Data Fusion Framework for Guiding the Visually Impaired

The world has approximately 253 million visually impaired (VI) people according to a report by the world health organization (WHO) in 2014. Thirty-six million people are estimated to be blind. According to WHO, 217 million people are estimated to have moderate to severe visual impairment. An important factor that motivated this research is the fact that 90% of VI people live in developing countries. Several systems were designed to improve the quality of the life of VI people and support their mobility. Unfortunately, none of these systems are considered to be a complete solution for VI people and these systems are very expensive. We present in this paper an intelligent framework for supporting VI people. The proposed work integrates sensor-based and computer vision-based techniques to provide an accurate and economical solution. These techniques allow us to detect multiple objects and enhance the accuracy of the collision avoidance system. In addition, we introduce a novel obstacle avoidance algorithm based on the image depth information and fuzzy logic. By using the fuzzy logic, we were able to provide precise information to help the VI user in avoiding front obstacles. The system has been deployed and tested in real-time scenarios. An accuracy of 98% was obtained for detecting objects and 100% accuracy in avoiding the detected objects.

UNIVERSITY WEBSITE ACCESSIBILITY FOR TOTALLY BLIND USERS

Researchers have discovered significant faults in the accessibility of university websites, especially for visually-impaired users. To determine the requirements for totally blind users, this study conducted a comprehensive literature review and accessibility evaluation on 15 Palestinian university websites. The determined factors were used in designing an accessible web page prototype. An online questionnaire was constructed to evaluate the accessibility of the prototype from the blind users’ perspective. From the evaluation of 16 blind participants, it was found that the prototype was highly accessible (mean score 4.19). The regression analysis test was utilised to determine the relationship between the items and the main principles of accessibility. The results show that there are statistically significant differences between these items. In conclusion, the accessibility factors have been indirectly validated.

A GPU-accelerated real-time contextual awareness application for the visually impaired on Google’s project Tango device

An application for the recently introduced Google Project Tango Tablet Development Kit to assist visually impaired (VI) users in understanding their environmental context by identifying and locating multiple faces and objects in their vicinity in real-time is presented. CUDA-based GPU-accelerated algorithms would be utilized to detect and recognize faces and objects from the visual data, while the locations of these entities relative to the user would be estimated from the depth data acquired via the tablet. The interaction would be speech based with the user being offered several options for requesting information about the identities and/or relative locations of face and objects. The aim is to create a portable, affordable, power-efficient, standalone assistive application to increase the autonomy of VI users which can run in real time on the device itself.

Promoting interactive television (iTV) accessibility: an adapted service for users with visual impairments

In spite of the wide dissemination of technologies and digital resources, people with special needs still find barriers and difficulties in accessing and using many of the information technology services currently available. This problem is particularly critical in usage scenarios involving mass media devices like television (TV), particularly taking in consideration its interactive format with all advanced features it brings. In this context, the creation of inclusion strategies becomes essential for increasing digital literacy and citizens' capacity to participate in different areas using advanced services such as interactive television (iTV). In this framework, this paper introduces a study from the Portuguese context regarding universal design issues on the iTV scope, which aims at the conceptualization, prototyping and validation of an iTV service specifically designed to look on visually impaired users' needs. With the development of this iTV service, the authors intend to allow access to adapted television content (such as audio described content) to visually impaired users (VIU), as well as making its user interface accessible for this type of users. The methodology of this study was based on the grounded theory (in the first stage) and the evaluative study method (in the second and third stage). In the first stage, the difficulties and needs of VIU as consumers of television contents and audio description services were identified. In the second stage, the adapted iTV prototype was conceptualized and developed. Regarding the third stage, it included the prototyped service evaluation by a group of visually impaired participants. In the end of the study, the participants who were involved in the prototype tests showed satisfaction with the features offered by the system as well as with the design of its interface.

Audio Description in Interactive Television (iTV): Proposal of a Collaborative and Voluntary Approach

Audio description (AD) is a media feature especially designed for visually impaired people to enable the access, via audio, to the description of visual content, such as television programs or movies, in which a narrator orally describes the visual scenes that are not perceptible by these users. Without this feature, unfortunately not available on a large scale, visually impaired users (VIU) have major difficulties in taking the best benefit of television contents.Currently, the production of AD is a costly and complex process, achieving only the minimum requirements mandated by what TV law obliges. However, the current technological convergence paradigm provides great opportunities to enhance this process, leveraging the number of AD and bringing relevant socio-economic impacts.In this context, this paper aims to describe some key steps to support the participatory development of a cross-platform prototype, which enable collaborative and voluntary creation of AD in an inclusive approach. A special focus is given to a preliminary test aiming to understand how the target audience responds to the designed collaborative strategy. Based on a qualitative evaluation, we found that volunteers were satisfied with the procedure used to create AD and visually impaired users felt that this AD assisted them.

Designing Media for Visually-Impaired Users of Refreshable Touch Displays: Possibilities and Pitfalls.

This paper discusses issues of importance to designers of media for visually impaired users. The paper considers the influence of human factors on the effectiveness of presentation as well as the strengths and weaknesses of tactile, vibrotactile, haptic, and multimodal methods of rendering maps, graphs, and models. The authors, all of whom are visually impaired researchers in this domain, present findings from their own work and work of many others who have contributed to the current understanding of how to prepare and render images for both hard-copy and technology-mediated presentation of Braille and tangible graphics.

Web challenges faced by blind and vision impaired users in libraries of Delhi

Purpose – The purpose of this paper is to analyse the challenges faced by blind/vision-impaired users during the web access in the leading academic and special libraries of Delhi, India. Design/methodology/approach – Survey methodology has been used as the basic research tool for data collection with the help of questionnaire. A total of 125 users surveyed in all the five libraries are selected randomly on the basis of willingness of the users to participate in the survey with the experience of working in digital environment. The survey results were tabulated and analysed with descriptive statistics methods using Excel software and “Stata version 11”. Findings – There are various barriers faced by blind/vision-impaired users in the libraries of Delhi (India) during the “web access” with the help of assistive technologies as assistive technology like “Screen Readers” available today are “somewhat compatible” with the web. The facility of “web-based catalogue” is generally lacking in Delhi libraries. Research limitations/implications – The paper does not offer a comprehensive set of web accessibility issues, concentrating instead on the most common problems as epitome of this study. Practical implications – The paper raises awareness of web accessibility issues in libraries of Delhi, India. Originality/value – The paper highlights the web accessibility issues faced by blind/vision-impaired users of leading academic and special libraries of India including the users’ recommendations for the accessible web page/website design for the first time.

Aerial obstacle detection with 3-D mobile devices.

In this paper, we present a novel approach for aerial obstacle detection (e.g., branches or awnings) using a 3-D smartphone in the context of the visually impaired (VI) people assistance. This kind of obstacles are especially challenging because they cannot be detected by the walking stick or the guide dog.The algorithm captures the 3-D data of the scene through stereo vision. To our knowledge, this is the first work that presents a technology able to obtain real 3-D measures with smartphones in real time. The orientation sensors of the device (magnetometer and accelerometer) are used to approximate the walking direction of the user, in order to look for the obstacles only in such a direction. The obtained 3-D data are compressed and then linearized for detecting the potential obstacles. Potential obstacles are tracked in order to accumulate enough evidence to alert the user only when a real obstacle is found.In the experimental section, we show the results of the algorithm in several situations using real data and helped by VI users.

Tactile and bone-conduction auditory brain computer interface for vision and hearing impaired users

BackgroundThe paper presents a report on the recently developed BCI alternative for users suffering from impaired vision (lack of focus or eye-movements) or from the so-called “ear-blocking-syndrome” (limited hearing). We report on our recent studies of the extents to which vibrotactile stimuli delivered to the head of a user can serve as a platform for a brain computer interface (BCI) paradigm. New methodIn the proposed tactile and bone-conduction auditory BCI novel multiple head positions are used to evoke combined somatosensory and auditory (via the bone conduction effect) P300 brain responses, in order to define a multimodal tactile and bone-conduction auditory brain computer interface (tbcaBCI). In order to further remove EEG interferences and to improve P300 response classification synchrosqueezing transform (SST) is applied. SST outperforms the classical time–frequency analysis methods of the non-linear and non-stationary signals such as EEG. The proposed method is also computationally more effective comparing to the empirical mode decomposition. The SST filtering allows for online EEG preprocessing application which is essential in the case of BCI. ResultsExperimental results with healthy BCI-naive users performing online tbcaBCI, validate the paradigm, while the feasibility of the concept is illuminated through information transfer rate case studies. Comparison with existing method(s)We present a comparison of the proposed SST-based preprocessing method, combined with a logistic regression (LR) classifier, together with classical preprocessing and LDA-based classification BCI techniques. ConclusionsThe proposed tbcaBCI paradigm together with data-driven preprocessing methods are a step forward in robust BCI applications research.

A wearable multipoint ultrasonic travel aids for visually impaired

In 2010, the World Health Organization estimates that there were about 285 million people in the world with disabling eyesight loss (246 millions are visually impaired (VI) and 39 millions are totally blind). For such users, hits during mobility tasks are the reason of major concerns and can reduce the quality of their life. The white cane is the primary device used by the majority of blind or VI users to explore and possibly avoid obstacles; it can monitor only the ground (< 1m) and it does not provide protection for the legs, the trunk and the head. In this paper, authors propose a novel stand-alone Electronic Travel Aid (ETA) device for obstacle detection based on multi- sensing (by 4 ultrasonic transducers) and a microcontroller. Portability, simplicity, reduced dimensions and cost are among the major pros of the reported system, which can detect and localize (angular position and distance from the user) obstacles eventually present in the volume in front of him and on the ground in front of him.

Multimodal eyes-free exploration of maps

Touch It, Key It, Speak It (Tikisi) is a software framework for accessible exploration of graphical information by vision impaired users. Multimodal input to Tikisi is through multitouch gestures, keystrokes, and spoken commands; output is generated speech. The key insight in Tikisi is the decoupling of input and output resolutions achieved by a virtual, variable-resolution grid overlaid on an application, which supports touch-based exploration of graphics at different levels of granularity. Using Tikisi For Maps, a vision impaired user can run a finger over a geographical map and issue commands to center, rescale, or zoom the map; to go to specific locations such as cities or states; to find features such as water/land boundaries; and to summarize contextual spatial information at a location. In this paper we describe the architecture and implementation of Tikisi and the capabilities of Tikisi For Maps. We discuss the results of a preliminary formative usability study carried out on the use of the system.

Assistive obstacle detection and navigation devices for vision-impaired users

Quality of life for the visually impaired is an urgent worldwide issue that needs to be addressed. Obstacle detection is one of the most important navigation tasks for the visually impaired. In this research, a novel range sensor placement scheme is proposed in this paper for the development of obstacle detection devices. Based on this scheme, two prototypes have been developed targeting at different user groups. This paper discusses the design issues, functional modules and the evaluation tests carried out for both prototypes.Implications for RehabilitationVisual impairment problem is becoming more severe due to the worldwide ageing population. Individuals with visual impairment require assistance from assistive devices in daily navigation tasks.Traditional assistive devices that assist navigation may have certain drawbacks, such as the limited sensing range of a white cane.Obstacle detection devices applying the range sensor technology can identify road conditions with a higher sensing range to notify the users of potential dangers in advance.

Lists, Spatial Practice and Assistive Technologies for the Blind

Lists, Spatial Practice and Assistive Technologies for the Blind

Fast and independent access to map directions for people who are blind

This article presents an automatic approach, complete with a prototype system, to supporting fast and independent access to online maps for local navigation by people with visual impairment. With user-inputted start and end addresses from a keyboard, the approach first queries MapQuest (www.mapquest.com) for obtaining the walking directions and the corresponding map image. Then, it automatically converts the obtained information in a form that can be reproduced immediately through a tactile printer, and subsequently generates an SVG (Scalable Vector Graphics) file, which associates textual descriptions of the directions with a recreated tactile map. The tactile hard copy can be placed on a touchpad which is connected to a computer. With the generated SVG file opened in the computer, a user can explore the tactile map by hands, receiving instant audio feedback of the directions by pressing certain regions with special tactile patterns. This approach supports instant queries of walking directions without requiring tedious manual conversion by a sighted professional. The audio-tactile patterns, the adaptive representation scheme and the blind-friendly user interface are specifically designed for the visually-impaired users. Results from experimental evaluation based on a group of users with visual impairment suggest that the proposed approach is effective for providing blind computer users with independent access to geographic directions.

Learning by E-Learning for Visually Impaired Students: Opportunities or Again Marginalisation?

In recent years, e-learning has become a valuable tool for an increasing number of visually impaired (VI) learners. The benefits of this technology include: (1) remote learning for VI students; (2) the possibility for teachers living far from schools or universities to provide remote instructional assistance to VI students; and (3) continuing education for VI adults. A number of studies confirm that VI students appreciate the advantages of e-learning systems, but they also have to face several challenges in pursuing their education through the e-learning mode. E-learning can be a valuable opportunity for VI users if suitable education methods and appropriate technologies are used. Hence, it is crucial to identify the needs and requirements of the target community in order to create a system that fulfils their expectations. This article describes the experiences of Indian VI learners with e-learning, throws light on the problems often encountered by them when using assistive technology and proposes guidelines for designers in order to develop more accessible e-learning systems.