Wearable Urban Mobility Assistive Device for Visually Impaired Pedestrians Using a Smartphone and a Tactile-Foot Interface

This paper reports on the progress of a wearable assistive technology (AT) device designed to enhance the independent, safe, and efficient mobility of blind and visually impaired pedestrians in outdoor environments. Such device exploits the smartphone’s positioning and computing capabilities to locate and guide users along urban settings. The necessary navigation instructions to reach a destination are encoded as vibrating patterns which are conveyed to the user via a foot-placed tactile interface. To determine the performance of the proposed AT device, two user experiments were conducted. The first one requested a group of 20 voluntary normally sighted subjects to recognize the feedback provided by the tactile-foot interface. The results showed recognition rates over 93%. The second experiment involved two blind voluntary subjects which were assisted to find target destinations along public urban pathways. Results show that the subjects successfully accomplished the task and suggest that blind and visually impaired pedes-trians might find the AT device and its concept approach useful, friendly, fast to master, and easy to use

HaptiSole: Wearable Haptic System in Vibrotactile Guidance Shoes for Visually Impaired Wayfinding

During the last decade, several Electronic Orientation Aids devices have been proposed to solve the autonomy problems of visually impaired people. When hearing is considered the primary sense for Visually Impaired people (VI) and it is generally loaded with the environment, the use of tactile sense can be considered a solution to transmit directional information. This paper presents a new wearable haptic system based on four motors implemented in shoes, while six directions can be played. This study aims to introduce an interface design and investigate an appropriate means of spatial information delivery through haptic sense. The first experiment of the proposed system was performed with 15 users in an indoor environment. The results showed that the users were able to recognize, with high accuracy, the directions displayed on their feet. The second experiment was conducted in an outdoor environment with five blindfolded users who were guided along 120 meters. The users, guided only by the haptic system, successfully reached their destinations. The potential of tactile-foot stimulation to help VI understand Electronic Orientation Aids (EOA) instructions was discussed, and future challenges were defined

Taux : a system for evaluating sound feedback in navigational tasks

This thesis presents the design and development of an evaluation system for generating audio displays that provide feedback to persons performing navigation tasks. It first develops the need for such a system by describing existing wayfinding solutions, investigating new electronic location-based methods that have the potential of changing these solutions and examining research conducted on relevant audio information representation techniques. An evaluation system that supports the manipulation of two basic classes of audio display is then described. Based on prior work on wayfinding with audio display, research questions are developed that investigate the viability of different audio displays. These are used to generate hypotheses and develop an experiment which evaluates four variations of audio display for wayfinding. Questions are also formulated that evaluate a baseline condition that utilizes visual feedback. An experiment which tests these hypotheses on sighted users is then described. Results from the experiment suggest that spatial audio combined with spoken hints is the best approach of the approaches comparing spatial audio. The test experiment results also suggest that muting a varying audio signal when a subject is on course did not improve performance. The system and method are then refined. A second experiment is conducted with improved displays and an improved experiment methodology. After adding blindfolds for sighted subjects and increasing the difficulty of navigation tasks by reducing the arrival radius, similar comparisons were observed. Overall, the two experiments demonstrate the viability of the prototyping tool for testing and refining multiple different audio display combinations for navigational tasks. The detailed contributions of this work and future research opportunities conclude this thesis

An Orientation & Mobility Aid for People with Visual Impairments

Orientierung&Mobilität (O&M) umfasst eine Reihe von Techniken für Menschen mit Sehschädigungen, die ihnen helfen, sich im Alltag zurechtzufinden. Dennoch benötigen sie einen umfangreichen und sehr aufwendigen Einzelunterricht mit O&M Lehrern, um diese Techniken in ihre täglichen Abläufe zu integrieren. Während einige dieser Techniken assistive Technologien benutzen, wie zum Beispiel den Blinden-Langstock, Points of Interest Datenbanken oder ein Kompass gestütztes Orientierungssystem, existiert eine unscheinbare Kommunikationslücke zwischen verfügbaren Hilfsmitteln und Navigationssystemen. In den letzten Jahren sind mobile Rechensysteme, insbesondere Smartphones, allgegenwärtig geworden. Dies eröffnet modernen Techniken des maschinellen Sehens die Möglichkeit, den menschlichen Sehsinn bei Problemen im Alltag zu unterstützen, die durch ein nicht barrierefreies Design entstanden sind. Dennoch muss mit besonderer Sorgfalt vorgegangen werden, um dabei nicht mit den speziellen persönlichen Kompetenzen und antrainierten Verhaltensweisen zu kollidieren, oder schlimmstenfalls O&M Techniken sogar zu widersprechen. In dieser Dissertation identifizieren wir eine räumliche und systembedingte Lücke zwischen Orientierungshilfen und Navigationssystemen für Menschen mit Sehschädigung. Die räumliche Lücke existiert hauptsächlich, da assistive Orientierungshilfen, wie zum Beispiel der Blinden-Langstock, nur dabei helfen können, die Umgebung in einem limitierten Bereich wahrzunehmen, während Navigationsinformationen nur sehr weitläufig gehalten sind. Zusätzlich entsteht diese Lücke auch systembedingt zwischen diesen beiden Komponenten — der Blinden-Langstock kennt die Route nicht, während ein Navigationssystem nahegelegene Hindernisse oder O&M Techniken nicht weiter betrachtet. Daher schlagen wir verschiedene Ansätze zum Schließen dieser Lücke vor, um die Verbindung und Kommunikation zwischen Orientierungshilfen und Navigationsinformationen zu verbessern und betrachten das Problem dabei aus beiden Richtungen. Um nützliche relevante Informationen bereitzustellen, identifizieren wir zuerst die bedeutendsten Anforderungen an assistive Systeme und erstellen einige Schlüsselkonzepte, die wir bei unseren Algorithmen und Prototypen beachten. Existierende assistive Systeme zur Orientierung basieren hauptsächlich auf globalen Navigationssatellitensystemen. Wir versuchen, diese zu verbessern, indem wir einen auf Leitlinien basierenden Routing Algorithmus erstellen, der auf individuelle Bedürfnisse anpassbar ist und diese berücksichtigt. Generierte Routen sind zwar unmerklich länger, aber auch viel sicherer, gemäß den in Zusammenarbeit mit O&M Lehrern erstellten objektiven Kriterien. Außerdem verbessern wir die Verfügbarkeit von relevanten georeferenzierten Datenbanken, die für ein derartiges bedarfsgerechtes Routing benötigt werden. Zu diesem Zweck erstellen wir einen maschinellen Lernansatz, mit dem wir Zebrastreifen in Luftbildern erkennen, was auch über Ländergrenzen hinweg funktioniert, und verbessern dabei den Stand der Technik. Um den Nutzen von Mobilitätsassistenz durch maschinelles Sehen zu optimieren, erstellen wir O&M Techniken nachempfundene Ansätze, um die räumliche Wahrnehmung der unmittelbaren Umgebung zu erhöhen. Zuerst betrachten wir dazu die verfügbare Freifläche und informieren auch über mögliche Hindernisse. Weiterhin erstellen wir einen neuartigen Ansatz, um die verfügbaren Leitlinien zu erkennen und genau zu lokalisieren, und erzeugen virtuelle Leitlinien, welche Unterbrechungen überbrücken und bereits frühzeitig Informationen über die nächste Leitlinie bereitstellen. Abschließend verbessern wir die Zugänglichkeit von Fußgängerübergängen, insbesondere Zebrastreifen und Fußgängerampeln, mit einem Deep Learning Ansatz. Um zu analysieren, ob unsere erstellten Ansätze und Algorithmen einen tatsächlichen Mehrwert für Menschen mit Sehschädigung erzeugen, vollziehen wir ein kleines Wizard-of-Oz-Experiment zu unserem bedarfsgerechten Routing — mit einem sehr ermutigendem Ergebnis. Weiterhin führen wir eine umfangreichere Studie mit verschiedenen Komponenten und dem Fokus auf Fußgängerübergänge durch. Obwohl unsere statistischen Auswertungen nur eine geringfügige Verbesserung aufzeigen, beeinflußt durch technische Probleme mit dem ersten Prototypen und einer zu geringen Eingewöhnungszeit der Probanden an das System, bekommen wir viel versprechende Kommentare von fast allen Studienteilnehmern. Dies zeigt, daß wir bereits einen wichtigen ersten Schritt zum Schließen der identifizierten Lücke geleistet haben und Orientierung&Mobilität für Menschen mit Sehschädigung damit verbessern konnten

3D oceanographic data compression using 3D-ODETLAP

This paper describes a 3D environmental data compression technique for oceanographic datasets. With proper point selection, our method approximates uncompressed marine data using an over-determined system of linear equations based on, but essentially different from, the Laplacian partial differential equation. Then this approximation is refined via an error metric. These two steps work alternatively until a predefined satisfying approximation is found. Using several different datasets and metrics, we demonstrate that our method has an excellent compression ratio. To further evaluate our method, we compare it with 3D-SPIHT. 3D-ODETLAP averages 20% better compression than 3D-SPIHT on our eight test datasets, from World Ocean Atlas 2005. Our method provides up to approximately six times better compression on datasets with relatively small variance. Meanwhile, with the same approximate mean error, we demonstrate a significantly smaller maximum error compared to 3D-SPIHT and provide a feature to keep the maximum error under a user-defined limit

Assessment of Audio Interfaces for use in Smartphone Based Spatial Learning Systems for the Blind

Recent advancements in the field of indoor positioning and mobile computing promise development of smart phone based indoor navigation systems. Currently, the preliminary implementations of such systems only use visual interfaces—meaning that they are inaccessible to blind and low vision users. According to the World Health Organization, about 39 million people in the world are blind. This necessitates the need for development and evaluation of non-visual interfaces for indoor navigation systems that support safe and efficient spatial learning and navigation behavior. This thesis research has empirically evaluated several different approaches through which spatial information about the environment can be conveyed through audio. In the first experiment, blindfolded participants standing at an origin in a lab learned the distance and azimuth of target objects that were specified by four audio modes. The first three modes were perceptual interfaces and did not require cognitive mediation on the part of the user. The fourth mode was a non-perceptual mode where object descriptions were given via spatial language using clockface angles. After learning the targets through the four modes, the participants spatially updated the position of the targets and localized them by walking to each of them from two indirect waypoints. The results also indicate hand motion triggered mode to be better than the head motion triggered mode and comparable to auditory snapshot. In the second experiment, blindfolded participants learned target object arrays with two spatial audio modes and a visual mode. In the first mode, head tracking was enabled, whereas in the second mode hand tracking was enabled. In the third mode, serving as a control, the participants were allowed to learn the targets visually. We again compared spatial updating performance with these modes and found no significant performance differences between modes. These results indicate that we can develop 3D audio interfaces on sensor rich off the shelf smartphone devices, without the need of expensive head tracking hardware. Finally, a third study, evaluated room layout learning performance by blindfolded participants with an android smartphone. Three perceptual and one non-perceptual mode were tested for cognitive map development. As expected the perceptual interfaces performed significantly better than the non-perceptual language based mode in an allocentric pointing judgment and in overall subjective rating. In sum, the perceptual interfaces led to better spatial learning performance and higher user ratings. Also there is no significant difference in a cognitive map developed through spatial audio based on tracking user’s head or hand. These results have important implications as they support development of accessible perceptually driven interfaces for smartphones

Walking and Walkability: Is Wayfinding a Missing Link? Implications for Public Health Practice

Research on walking and walkability has yet to focus on wayfinding, the interactive, problem-solving process by which people use environmental information to locate themselves and navigate through various settings

Architecture for the visually impaired : design of a Society for the Blind.

Thesis (M.Arch.)-University of KwaZulu-Natal, Durban, 2008.This dissertation documents the research involved in determining an appropriate response for the design of a building which serves to provide tools for empowerment and independence for blind and partially sighted people. Primary and secondary data collection methods are used. Secondary data collection forms the majority of information gathered focusing on precedent and case studies. The studies investigate how buildings are currently occupied, discussing the differences between buildings that have been specifically designed for the visually impaired and those that have not. Analysis observes the problems that exist and what solutions have been proposed to overcome these. Design criteria can focus on detail design exclusively; however the building in its entirety can be custom-designed to meet the needs of the visually impaired user. This dissertation explores architecture as a sensory experience, highlighting findings that can be used when designing buildings specifically for visually impaired users. The visually impaired rely heavily on their senses enabling them to interpret their surroundings. This research includes an exploration into the use of the senses within the built environment and how we as sighted designers can understand, interpret and contribute to a visually impaired person's experience of the built environment. The research concludes on an appropriate response to designing for visually impaired people. Conclusions are drawn and a design brief for a facility for a Society for the Blind derived

Tactile Displays for Pedestrian Navigation

Existing pedestrian navigation systems are mainly visual-based, sometimes with an addition of audio guidance. However, previous research has reported that visual-based navigation systems require a high level of cognitive efforts, contributing to errors and delays. Furthermore, in many situations a person’s visual and auditory channels may be compromised due to environmental factors or may be occupied by other important tasks. Some research has suggested that the tactile sense can effectively be used for interfaces to support navigation tasks. However, many fundamental design and usability issues with pedestrian tactile navigation displays are yet to be investigated. This dissertation investigates human-computer interaction aspects associated with the design of tactile pedestrian navigation systems. More specifically, it addresses the following questions: What may be appropriate forms of wearable devices? What types of spatial information should such systems provide to pedestrians? How do people use spatial information for different navigation purposes? How can we effectively represent such information via tactile stimuli? And how do tactile navigation systems perform? A series of empirical studies was carried out to (1) investigate the effects of tactile signal properties and manipulation on the human perception of spatial data, (2) find out the effective form of wearable displays for navigation tasks, and (3) explore a number of potential tactile representation techniques for spatial data, specifically representing directions and landmarks. Questionnaires and interviews were used to gather information on the use of landmarks amongst people navigating urban environments for different purposes. Analysis of the results of these studies provided implications for the design of tactile pedestrian navigation systems, which we incorporated in a prototype. Finally, field trials were carried out to evaluate the design and address usability issues and performance-related benefits and challenges. The thesis develops an understanding of how to represent spatial information via the tactile channel and provides suggestions for the design and implementation of tactile pedestrian navigation systems. In addition, the thesis classifies the use of various types of landmarks for different navigation purposes. These contributions are developed throughout the thesis building upon an integrated series of empirical studies.EThOS - Electronic Theses Online ServiceGBUnited Kingdo