Exploring User Requirements for Non-visual Mobile Navigation Systems

This paper describes an explorative user study of how two different user groups experience current, as well as envisioned new mobile navigation systems. Two groups have been the primary target in this study; a group of elderly people and a group of relatively young university students that were visually impaired. The study consisted of three parts: a focus group/test, a diary study and a design workshop where the users envisioned new kinds of interaction with mobile navigation systems by building and demonstrating low-fi prototypes. Information about user requirements for these types of applications is obtained and we observe features in the study design which are relevant for a wider range of mobile services

A Formal Approach to Computer Aided 2D Graphical Design for Blind People

The growth of computer aided drawing systems for blind people (CADB) has long been recognised and has increased in interest within the assistive technology research area. The representation of pictorial data by blind and visually impaired (BVI) people has recently gathered momentum with research and development; however, a survey of published literature on CADB reveals that only marginal research has been focused on the use of a formal approach for on screen spatial orientation, creation and reuse of graphics artefacts. To realise the full potential of CADB, such systems should possess attributes of usability, spatial navigation and shape creation features without which blind users drawing activities are less likely to be achieved. As a result of this, usable, effective and self-reliant CADB have arisen from new assistive Technology (AT) research. This thesis contributes a novel, abstract, formal approach that facilitates BVI users to navigate on the screen, create computer graphics/diagrams using 2D shapes and user-defined images. Moreover, the research addresses the specific issues involved with user language by formulating specific rules that make BVI user interaction with the drawing effective and easier. The formal approach proposed here is descriptive and it is specified at a level of abstraction above the concrete level of system technologies. The proposed approach is unique in problem modelling and syntheses of an abstract computer-based graphics/drawings using a formal set of user interaction commands. This technology has been applied to enable blind users to independently construct drawings to satisfy their specific needs without recourse to a specific technology and without the intervention of support workers. The specification aims to be the foundation for a system scope, investigation guidelines and user-initiated command-driven interaction. Such an approach will allow system designers and developers to proceed with greater conceptual clarity than it is possible with current technologies that is built on concrete system-driven prototypes. In addition to the scope of the research the proposed model has been verified by various types of blind users who have independently constructed drawings to satisfy their specific needs without the intervention of support workers. The effectiveness and usability of the proposed approach has been compared against conventional non-command driven drawing systems by different types of blind users. The results confirm that the abstract formal approach proposed here using command-driven means in the context of CADB enables greater comprehension by BVI users. The innovation can be used for both educational and training purposes. The research, thereby sustaining the claim that the abstract formal approach taken allows for the greater comprehension of the command-driven means in the context of CADB, and how the specification aid the design of such a system

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