A Systematic Review of Urban Navigation Systems for Visually Impaired People

Blind and Visually impaired people (BVIP) face a range of practical difficulties when undertaking outdoor journeys as pedestrians. Over the past decade, a variety of assistive devices have been researched and developed to help BVIP navigate more safely and independently. In~addition, research in overlapping domains are addressing the problem of automatic environment interpretation using computer vision and machine learning, particularly deep learning, approaches. Our aim in this article is to present a comprehensive review of research directly in, or relevant to, assistive outdoor navigation for BVIP. We breakdown the navigation area into a series of navigation phases and tasks. We then use this structure for our systematic review of research, analysing articles, methods, datasets and current limitations by task. We also provide an overview of commercial and non-commercial navigation applications targeted at BVIP. Our review contributes to the body of knowledge by providing a comprehensive, structured analysis of work in the domain, including the state of the art, and guidance on future directions. It will support both researchers and other stakeholders in the domain to establish an informed view of research progress

IO Vision – an integrated system to support the visually impaired

Security questions are one of the techniques used to recover passwords. The main limitation of security questions is that users find strong answers difficult to remember. This leads users to trade-off security for the convenience of an improved memorability. Previous research found that increased fun and enjoyment can lead to an enhanced memorability, which provides a better learning experience. Hence, we empirically investigate whether a serious game has the potential of improving the memorability of strong answers to security questions. For our serious game, we adopted the popular “4 Pics 1 word” mobile game because of its use of pictures and cues, which psychology research found to be important to help with memorability. Our findings indicate that the proposed serious game could potentially improve the memorability of answers to security questions. This potential improvement in memorability, could eventually help reduce the trade-off between usability and security in fall-back authentication

Using wrist vibrations to guide hand movement and whole body navigation

International audienceIn the absence of vision, mobility and orientation are challenging. Audio and tactile feedback can be used to guide visually impaired people. In this paper, we present two complementary studies on the use of vibrational cues for hand guidance during the exploration of itineraries on a map, and whole body-guidance in a virtual environment. Concretely, we designed wearable Arduino bracelets integrating a vibratory motor producing multiple patterns of pulses. In a first study, this bracelet was used for guiding the hand along unknown routes on an interactive tactile map. A wizard-of-Oz study with six blindfolded participants showed that tactons, vibrational patterns, may be more efficient than audio cues for indicating directions. In a second study, this bracelet was used by blindfolded participants to navigate in a virtual environment. The results presented here show that it is possible to significantly decrease travel distance with vibrational cues. To sum up, these preliminary but complementary studies suggest the interest of vibrational feedback in assistive technology for mobility and orientation for blind people

Wayfinding and Navigation for People with Disabilities Using Social Navigation Networks

To achieve safe and independent mobility, people usually depend on published information, prior experience, the knowledge of others, and/or technology to navigate unfamiliar outdoor and indoor environments. Today, due to advances in various technologies, wayfinding and navigation systems and services are commonplace and are accessible on desktop, laptop, and mobile devices. However, despite their popularity and widespread use, current wayfinding and navigation solutions often fail to address the needs of people with disabilities (PWDs). We argue that these shortcomings are primarily due to the ubiquity of the compute-centric approach adopted in these systems and services, where they do not benefit from the experience-centric approach. We propose that following a hybrid approach of combining experience-centric and compute-centric methods will overcome the shortcomings of current wayfinding and navigation solutions for PWDs

Literature Review: Orientation and Mobility Assistive Technology for Students with Visual Impairment

The development of increasingly sophisticated technology is accompanied by the discovery of new assistive devices that should be accessible to all people, including the blind in order to maintain or improve functions so as to improve welfare. This study uses a literature review method with descriptive analysis by analyzing 20 articles. The purpose of this research is to examine more related to assistive technology for the blind in navigating indoors and outdoors including buildings and the accessibility of public services. The literature search was carried out through an electronic search for publications from ERIC, Researchgate, Spingerlink, Sage, Science Direct, Google Scholar and IEEE Xplore. The results of the study describe the use of various assistive technologies for the visually impaired related to navigation in spaces or buildings and even the wider environment as well as public services that are commonly accessed by the public. Furthermore, it is related to the existence of a brief description of the assistive technology developed and the benefits of the results of the development for users

A survey on computer vision technology in Camera Based ETA devices

Electronic Travel Aid systems are expected to make impaired persons able to perform their everyday tasks such as finding an object and avoiding obstacles easier. Among ETA devices, Camera Based ETA devices are the new one and with a high potential for helping Visually Impaired Persons. With recent advances in computer science and specially computer vision, Camera Based ETA devices used several computer vision algorithms and techniques such as object recognition and stereo vision in order to help VIP to perform tasks such as reading banknotes, recognizing people and avoiding obstacles. This paper analyses and appraises a number of literatures in this area with focus on stereo vision technique. Finally, after discussing about the methods and techniques used in different literatures, it is concluded that the stereo vision is the best technique for helping VIP in their everyday navigation

Smart Assistive Technology for People with Visual Field Loss

Visual field loss results in the lack of ability to clearly see objects in the surrounding environment, which affects the ability to determine potential hazards. In visual field loss, parts of the visual field are impaired to varying degrees, while other parts may remain healthy. This defect can be debilitating, making daily life activities very stressful. Unlike blind people, people with visual field loss retain some functional vision. It would be beneficial to intelligently augment this vision by adding computer-generated information to increase the users' awareness of possible hazards by providing early notifications. This thesis introduces a smart hazard attention system to help visual field impaired people with their navigation using smart glasses and a real-time hazard classification system. This takes the form of a novel, customised, machine learning-based hazard classification system that can be integrated into wearable assistive technology such as smart glasses. The proposed solution provides early notifications based on (1) the visual status of the user and (2) the motion status of the detected object. The presented technology can detect multiple objects at the same time and classify them into different hazard types. The system design in this work consists of four modules: (1) a deep learning-based object detector to recognise static and moving objects in real-time, (2) a Kalman Filter-based multi-object tracker to track the detected objects over time to determine their motion model, (3) a Neural Network-based classifier to determine the level of danger for each hazard using its motion features extracted while the object is in the user's field of vision, and (4) a feedback generation module to translate the hazard level into a smart notification to increase user's cognitive perception using the healthy vision within the visual field. For qualitative system testing, normal and personalised defected vision models were implemented. The personalised defected vision model was created to synthesise the visual function for the people with visual field defects. Actual central and full-field test results were used to create a personalised model that is used in the feedback generation stage of this system, where the visual notifications are displayed in the user's healthy visual area. The proposed solution will enhance the quality of life for people suffering from visual field loss conditions. This non-intrusive, wearable hazard detection technology can provide obstacle avoidance solution, and prevent falls and collisions early with minimal information

Mental maps and the use of sensory information by blind and partially sighted people

This article aims to fill an important gap in the literature by reporting on blind and partially sighted people's use of spatial representations (mental maps) from their perspective and when travelling on real routes. The results presented here were obtained from semi-structured interviews with 100 blind and partially sighted people in five different countries. They are intended to answer three questions about the representation of space by blind and partially sighted people, how these representations are used to support travel, and the implications for the design of travel aids and orientation and mobility training. They show that blind and partially sighted people do have spatial representations and that a number of them explicitly use the term mental map. This article discusses the variety of approaches to spatial representations, including the sensory modalities used, the use of global or local representations, and the applications to support travel. The conclusions summarize the answers to the three questions and include a two-level preliminary classification of the spatial representations of blind and partially sighted people