ASSISTIVE TECHNOLOGIES ON MOBILE DEVICES FOR PEOPLE WITH VISUAL IMPAIRMENTS

Spatial understanding and cognitive mapping are challenging tasks for people with visual impairments. The goal of this work is to leverage computer vision and spatial understanding techniques along with audio-haptic proprioceptive interaction paradigms for assisting people with visual impairments in spatial comprehension and memorization. Abstract space exploration in the field of assistive didactics is tackled through tactile exploration and audio feedback resulting in two solutions. The first one focuses on math learning in primary education while the second one focuses on function graph tactile exploration and sonification. In the field of spatial comprehension during way-finding for people with visual impairments, computer vision and spatial reasoning techniques are used for detecting visual cues such as zebra pedestrian crossings and for safely guiding the user with respect to the detected elements. Suitable interaction paradigms based on sonification and haptic feedback are designed to assist the user efficiently and quickly during the navigation

Outdoor Localization Using BLE RSSI and Accessible Pedestrian Signals for the Visually Impaired at Intersections

One of the major challenges for blind and visually impaired (BVI) people is traveling safely to cross intersections on foot. Many countries are now generating audible signals at crossings for visually impaired people to help with this problem. However, these accessible pedestrian signals can result in confusion for visually impaired people as they do not know which signal must be interpreted for traveling multiple crosses in complex road architecture. To solve this problem, we propose an assistive system called CAS (Crossing Assistance System) which extends the principle of the BLE (Bluetooth Low Energy) RSSI (Received Signal Strength Indicator) signal for outdoor and indoor location tracking and overcomes the intrinsic limitation of outdoor noise to enable us to locate the user effectively. We installed the system on a real-world intersection and collected a set of data for demonstrating the feasibility of outdoor RSSI tracking in a series of two studies. In the first study, our goal was to show the feasibility of using outdoor RSSI on the localization of four zones. We used a k-nearest neighbors (kNN) method and showed it led to 99.8% accuracy. In the second study, we extended our work to a more complex setup with nine zones, evaluated both the kNN and an additional method, a Support Vector Machine (SVM) with various RSSI features for classification. We found that the SVM performed best using the RSSI average, standard deviation, median, interquartile range (IQR) of the RSSI over a 5 s window. The best method can localize people with 97.7% accuracy. We conclude this paper by discussing how our system can impact navigation for BVI users in outdoor and indoor setups and what are the implications of these findings on the design of both wearable and traffic assistive technology for blind pedestrian navigation

SLAM for Visually Impaired People: A Survey

In recent decades, several assistive technologies for visually impaired and blind (VIB) people have been developed to improve their ability to navigate independently and safely. At the same time, simultaneous localization and mapping (SLAM) techniques have become sufficiently robust and efficient to be adopted in the development of assistive technologies. In this paper, we first report the results of an anonymous survey conducted with VIB people to understand their experience and needs; we focus on digital assistive technologies that help them with indoor and outdoor navigation. Then, we present a literature review of assistive technologies based on SLAM. We discuss proposed approaches and indicate their pros and cons. We conclude by presenting future opportunities and challenges in this domain.Comment: 26 pages, 5 tables, 3 figure

Touch- and Walkable Virtual Reality to Support Blind and Visually Impaired Peoples‘ Building Exploration in the Context of Orientation and Mobility

Der Zugang zu digitalen Inhalten und Informationen wird immer wichtiger für eine erfolgreiche Teilnahme an der heutigen, zunehmend digitalisierten Zivilgesellschaft. Solche Informationen werden meist visuell präsentiert, was den Zugang für blinde und sehbehinderte Menschen einschränkt. Die grundlegendste Barriere ist oft die elementare Orientierung und Mobilität (und folglich die soziale Mobilität), einschließlich der Erlangung von Kenntnissen über unbekannte Gebäude vor deren Besuch. Um solche Barrieren zu überbrücken, sollten technische Hilfsmittel entwickelt und eingesetzt werden. Es ist ein Kompromiss zwischen technologisch niedrigschwellig zugänglichen und verbreitbaren Hilfsmitteln und interaktiv-adaptiven, aber komplexen Systemen erforderlich. Die Anpassung der Technologie der virtuellen Realität (VR) umfasst ein breites Spektrum an Entwicklungs- und Entscheidungsoptionen. Die Hauptvorteile der VR-Technologie sind die erhöhte Interaktivität, die Aktualisierbarkeit und die Möglichkeit, virtuelle Räume und Modelle als Abbilder von realen Räumen zu erkunden, ohne dass reale Gefahren und die begrenzte Verfügbarkeit von sehenden Helfern auftreten. Virtuelle Objekte und Umgebungen haben jedoch keine physische Beschaffenheit. Ziel dieser Arbeit ist es daher zu erforschen, welche VR-Interaktionsformen sinnvoll sind (d.h. ein angemessenes Verbreitungspotenzial bieten), um virtuelle Repräsentationen realer Gebäude im Kontext von Orientierung und Mobilität berührbar oder begehbar zu machen. Obwohl es bereits inhaltlich und technisch disjunkte Entwicklungen und Evaluationen zur VR-Technologie gibt, fehlt es an empirischer Evidenz. Zusätzlich bietet diese Arbeit einen Überblick über die verschiedenen Interaktionen. Nach einer Betrachtung der menschlichen Physiologie, Hilfsmittel (z.B. taktile Karten) und technologischen Eigenschaften wird der aktuelle Stand der Technik von VR vorgestellt und die Anwendung für blinde und sehbehinderte Nutzer und der Weg dorthin durch die Einführung einer neuartigen Taxonomie diskutiert. Neben der Interaktion selbst werden Merkmale des Nutzers und des Geräts, der Anwendungskontext oder die nutzerzentrierte Entwicklung bzw. Evaluation als Klassifikatoren herangezogen. Begründet und motiviert werden die folgenden Kapitel durch explorative Ansätze, d.h. im Bereich 'small scale' (mit sogenannten Datenhandschuhen) und im Bereich 'large scale' (mit einer avatargesteuerten VR-Fortbewegung). Die folgenden Kapitel führen empirische Studien mit blinden und sehbehinderten Nutzern durch und geben einen formativen Einblick, wie virtuelle Objekte in Reichweite der Hände mit haptischem Feedback erfasst werden können und wie verschiedene Arten der VR-Fortbewegung zur Erkundung virtueller Umgebungen eingesetzt werden können. Daraus werden geräteunabhängige technologische Möglichkeiten und auch Herausforderungen für weitere Verbesserungen abgeleitet. Auf der Grundlage dieser Erkenntnisse kann sich die weitere Forschung auf Aspekte wie die spezifische Gestaltung interaktiver Elemente, zeitlich und räumlich kollaborative Anwendungsszenarien und die Evaluation eines gesamten Anwendungsworkflows (d.h. Scannen der realen Umgebung und virtuelle Erkundung zu Trainingszwecken sowie die Gestaltung der gesamten Anwendung in einer langfristig barrierefreien Weise) konzentrieren.Access to digital content and information is becoming increasingly important for successful participation in today's increasingly digitized civil society. Such information is mostly presented visually, which restricts access for blind and visually impaired people. The most fundamental barrier is often basic orientation and mobility (and consequently, social mobility), including gaining knowledge about unknown buildings before visiting them. To bridge such barriers, technological aids should be developed and deployed. A trade-off is needed between technologically low-threshold accessible and disseminable aids and interactive-adaptive but complex systems. The adaptation of virtual reality (VR) technology spans a wide range of development and decision options. The main benefits of VR technology are increased interactivity, updatability, and the possibility to explore virtual spaces as proxies of real ones without real-world hazards and the limited availability of sighted assistants. However, virtual objects and environments have no physicality. Therefore, this thesis aims to research which VR interaction forms are reasonable (i.e., offering a reasonable dissemination potential) to make virtual representations of real buildings touchable or walkable in the context of orientation and mobility. Although there are already content and technology disjunctive developments and evaluations on VR technology, there is a lack of empirical evidence. Additionally, this thesis provides a survey between different interactions. Having considered the human physiology, assistive media (e.g., tactile maps), and technological characteristics, the current state of the art of VR is introduced, and the application for blind and visually impaired users and the way to get there is discussed by introducing a novel taxonomy. In addition to the interaction itself, characteristics of the user and the device, the application context, or the user-centered development respectively evaluation are used as classifiers. Thus, the following chapters are justified and motivated by explorative approaches, i.e., in the group of 'small scale' (using so-called data gloves) and in the scale of 'large scale' (using an avatar-controlled VR locomotion) approaches. The following chapters conduct empirical studies with blind and visually impaired users and give formative insight into how virtual objects within hands' reach can be grasped using haptic feedback and how different kinds of VR locomotion implementation can be applied to explore virtual environments. Thus, device-independent technological possibilities and also challenges for further improvements are derived. On the basis of this knowledge, subsequent research can be focused on aspects such as the specific design of interactive elements, temporally and spatially collaborative application scenarios, and the evaluation of an entire application workflow (i.e., scanning the real environment and exploring it virtually for training purposes, as well as designing the entire application in a long-term accessible manner)

Computer Vision-Powered Applications for Interpreting and Interacting with Movement

Movement and our ability to perceive it are core elements of the human experience. To bridge the gap between artificial intelligence research and the daily lives of people, this thesis explores leveraging advancements in the field of computer vision to enhance human experiences related to movement. Through two projects, I leverage computer vision to aid Blind and Low Vision (BLV) people in perceiving sports gameplay, and provide navigation assistance for pedestrians in outdoor urban environments. I present Front Row, a system that enables BLV viewers to interpret tennis matches through immersive audio cues, along with StreetNav, a system that repurposes street cameras for real-time, precise outdoor navigation assistance and environmental awareness. User studies and technical evaluations demonstrate the potential of these systems in augmenting people’s experiences perceiving and interacting with movement. This exploration also uncovers challenges in deploying such solutions along with opportunities in the design of future technologies. Keywords: human-centered computing, accessibility, computer vision, outdoor navigatio

Ontology of accessibility in the context of wayfinding for people with disabilities.

There is evidence that objects in and of the built environment function as barriers or facilitators to accessibility for people with disabilities. Although there are many existing sources of information about accessibility, they often lack clear criteria to describe accessibility, explanations of barriers and facilitators to mobility, and coverage of multiple physical environments. Researchers have argued that wayfinding services (e.g., Google Maps) can help people with disabilities prepare to travel through the built environment, yet current wayfinding services include little to no information about accessibility. This dissertation aims to study accessibility, in the context of wayfinding, in indoor, outdoor and transitional environments for people who travel in wheelchairs and people with low to no vision. To this end, a qualitative ontological analysis of multiple sources of information regarding accessibility was conducted including analyses of important categories associated with accessible wayfinding; different information providers’ views on accessibility; and specific barriers and facilitators to accessibility. The results indicate that (1) people with low to no vision and people who travel in wheelchairs have different core wayfinding information needs, (2) a gap exists between the information people with disabilities and researchers provide on accessibility and that provided by standard guidelines, and (3) conceptualizing accessibility requires capturing actions performed by people with disabilities during every day travel along with characteristics of environmental objects. The resulting ontology could be leveraged to generate new criteria describing accessibility, new routing algorithms, or to attach provenance to existing accessibility criteria. The findings have implications for people who design wayfinding services and collaborative maps and people collaboratively collecting data on the accessibility of specific places

A competencies framework of visual impairments for enabling shared understanding in design

Existing work in Human Computer Interaction and accessibility research has long sought to investigate the experiences of people with visual impairments in order to address their needs through technology design and integrate their participation into different stages of the design process. Yet challenges remain regarding how disabilities are framed in technology design and the extent of involvement of disabled people within it. Furthermore, accessibility is often considered a specialised job and misunderstandings or assumptions about visually impaired people’s experiences and needs occur outside dedicated fields. This thesis presents an ethnomethodology-informed design critique for supporting awareness and shared understanding of visual impairments and accessibility that centres on their experiences, abilities, and participation in early-stage design. This work is rooted in an in-depth empirical investigation of the interactional competencies that people with visual impairments exhibit through their use of technology, which informs and shapes the concept of a Competencies Framework of Visual Impairments. Although past research has established stances for considering the individual abilities of disabled people and other social and relational factors in technology design, by drawing on ethnomethodology and its interest in situated competence this thesis employs an interactional perspective to investigate the practical accomplishments of visually impaired people. Thus, this thesis frames visual impairments in terms of competencies to be considered in the design process, rather than a deficiency or problem to be fixed through technology. Accordingly, this work favours supporting awareness and reflection rather than the design of particular solutions, which are also strongly needed for advancing accessible design at large. This PhD thesis comprises two main empirical studies branched into three different investigations. The first and second investigations are based on a four-month ethnographic study with visually impaired participants examining their everyday technology practices. The third investigation comprises the design and implementation of a workshop study developed to include people with and without visual impairments in collaborative reflections about technology and accessibility. As such, each investigation informed the ones that followed, revisiting and refining concepts and design materials throughout the thesis. Although ethnomethodology is the overarching approach running through this PhD project, each investigation has a different focus of enquiry: • The first is focused on analysing participants’ technology practices and unearthing the interactional competencies enabling them. • The second is focused on analysing technology demonstrations, which were a pervasive phenomenon recorded during fieldwork, and the work of demonstrating as exhibited by visually impaired participants. • Lastly, the third investigation defines a workshop approach employing video demonstrations and a deck of reflective design cards as building blocks for enabling shared understanding among people with and without visual impairments from different technology backgrounds; that is, users, technologists, designers, and researchers. Overall, this thesis makes several contributions to audiences within and outside academia, such as the detailed accounts of some of the main technology practices of people with visual impairments and the methodological analysis of demonstrations in empirical Human Computer Interaction and accessibility research. Moreover, the main contribution lies in the conceptualisation of a Competencies Framework of Visual Impairments from the empirical analysis of interactional competencies and their practical exhibition through demonstrations, as well as the creation and use of a deck of cards that encapsulates the competencies and external elements involved in the everyday interactional accomplishments of people with visual impairments. All these contributions are lastly brought together in the implementation of the workshop approach that enabled participants to interact with and learn from each other. Thus, this thesis builds upon and advances contemporary strands of work in Human Computer Interaction that call for re-orienting how visual impairments and, overall, disabilities are framed in technology design, and ultimately for re-shaping the design practice itself

A competencies framework of visual impairments for enabling shared understanding in design

Existing work in Human Computer Interaction and accessibility research has long sought to investigate the experiences of people with visual impairments in order to address their needs through technology design and integrate their participation into different stages of the design process. Yet challenges remain regarding how disabilities are framed in technology design and the extent of involvement of disabled people within it. Furthermore, accessibility is often considered a specialised job and misunderstandings or assumptions about visually impaired people’s experiences and needs occur outside dedicated fields. This thesis presents an ethnomethodology-informed design critique for supporting awareness and shared understanding of visual impairments and accessibility that centres on their experiences, abilities, and participation in early-stage design. This work is rooted in an in-depth empirical investigation of the interactional competencies that people with visual impairments exhibit through their use of technology, which informs and shapes the concept of a Competencies Framework of Visual Impairments. Although past research has established stances for considering the individual abilities of disabled people and other social and relational factors in technology design, by drawing on ethnomethodology and its interest in situated competence this thesis employs an interactional perspective to investigate the practical accomplishments of visually impaired people. Thus, this thesis frames visual impairments in terms of competencies to be considered in the design process, rather than a deficiency or problem to be fixed through technology. Accordingly, this work favours supporting awareness and reflection rather than the design of particular solutions, which are also strongly needed for advancing accessible design at large. This PhD thesis comprises two main empirical studies branched into three different investigations. The first and second investigations are based on a four-month ethnographic study with visually impaired participants examining their everyday technology practices. The third investigation comprises the design and implementation of a workshop study developed to include people with and without visual impairments in collaborative reflections about technology and accessibility. As such, each investigation informed the ones that followed, revisiting and refining concepts and design materials throughout the thesis. Although ethnomethodology is the overarching approach running through this PhD project, each investigation has a different focus of enquiry: • The first is focused on analysing participants’ technology practices and unearthing the interactional competencies enabling them. • The second is focused on analysing technology demonstrations, which were a pervasive phenomenon recorded during fieldwork, and the work of demonstrating as exhibited by visually impaired participants. • Lastly, the third investigation defines a workshop approach employing video demonstrations and a deck of reflective design cards as building blocks for enabling shared understanding among people with and without visual impairments from different technology backgrounds; that is, users, technologists, designers, and researchers. Overall, this thesis makes several contributions to audiences within and outside academia, such as the detailed accounts of some of the main technology practices of people with visual impairments and the methodological analysis of demonstrations in empirical Human Computer Interaction and accessibility research. Moreover, the main contribution lies in the conceptualisation of a Competencies Framework of Visual Impairments from the empirical analysis of interactional competencies and their practical exhibition through demonstrations, as well as the creation and use of a deck of cards that encapsulates the competencies and external elements involved in the everyday interactional accomplishments of people with visual impairments. All these contributions are lastly brought together in the implementation of the workshop approach that enabled participants to interact with and learn from each other. Thus, this thesis builds upon and advances contemporary strands of work in Human Computer Interaction that call for re-orienting how visual impairments and, overall, disabilities are framed in technology design, and ultimately for re-shaping the design practice itself

An investigation into automatically generated auditory route overviews and their role in strategic route planning.

PhD ThesesMaps are an integral tool for supporting travellers to preview and plan their journeys. However, the process is predominantly visual and thus inaccessible to people who are blind or visually impaired (BVI). This work investigates the usefulness and design of providing apriori overviews of pedestrian routes in audio to support BVI individuals make strategic decisions regarding their journeys and prepare for them. A user-led approach was adopted throughout, from needs-assessment and requirement gathering, to design decisions and eventually usability and usefulness evaluation. The overviews designed comprised auditory icons(AIs) to represent points of interest (PoIs), earcons for auditory brackets encapsulating repeating or extended PoIs, and speech for directions. The findings showed that the BVI users performed well in route reconstruction and recognition tasks during usability testing. The functional route information and AIs were effectively designed and useful in forming a mental model of the route, which improves with usage. The usefulness study showed that the users used this information to make strategic pre-navigation decisions, such as which route to choose, and to learn about the different features of the route. The main focus of their choices was the reason for travel. Moreover, the two major priorities for blind travellers were safety and not getting lost and the two major features of the route that affected route choice were PoIs and length of the route

Sensory Urbanism Proceedings 2008

This book contains papers from the January 2008 conference, Sensory Urbanism, held by the University of Strathclyde, Glasgow, UK. Papers deal with issues surrounding the sensory perception of urban design and how to design better for all the senses. The book is illustrated throughout, and contains 26 papers from fields including architecture, urban design, environmental psychology, urban design, planning, sound design and more