A multimodal smartphone interface for active perception by visually impaired

The diffuse availability of mobile devices, such as smartphones and tablets, has the potential to bring substantial benefits to the people with sensory impairments. The solution proposed in this paper is part of an ongoing effort to create an accurate obstacle and hazard detector for the visually impaired, which is embedded in a hand-held device. In particular, it presents a proof of concept for a multimodal interface to control the orientation of a smartphone's camera, while being held by a person, using a combination of vocal messages, 3D sounds and vibrations. The solution, which is to be evaluated experimentally by users, will enable further research in the area of active vision with human-in-the-loop, with potential application to mobile assistive devices for indoor navigation of visually impaired people

Investigating design issues of context-aware mobile guides for people with visual impairments

While mobile wayfinding systems for visually impaired people offer huge potential, most insufficiently address the differences between visual impairments and contextual environments, and offer very little context-awareness - usability issues of which are vital in supporting independent mobility. Participants experiencing a loss of central vision, loss of peripheral vision, and total vision loss made up three groups. Our multidisciplinary model of context was used to design a user study, which involved asking participants to walk to pre-determined outdoor and indoor landmarks. Significant differences were found between groups relating to information requirements, and the environmental cues encoded and used to orientate and navigate. The study also found differences between indoor and outdoor contexts. It was concluded that what is meaningful to one form of visual impairment is incidental to another. These issues need to be captured and accounted for if wayfinding systems are to be usable

Perceptual impact of environmental factors in sighted and visually impaired individuals

To a visually impaired individual the physical world presents many challenges. For a person with impaired sight, wayfinding through a complex environment is fraught with dangers, both actual and imagined. The current generation of mobility aids have the possibility of addressing a broad range of physical issues through technological solutions. The perception of difficulty however, can mean that many visually impaired individuals are fearful or uncomfortable about independent mobility or travel. In this context it becomes necessary to discover exactly what environments, environmental factors or items constitute a ‘perception of difficulty’ in the individuals mental landscape and may trigger a negative response before they interact with the physical environment. This paper reports on research, which sought to ascertain what levels of perceptual difficulties specific environments and factors presented to individuals. The research was conducted with both visually impaired and sighted groups and compared differences and similarities in perceptual difficulty between these two groups

A pathway to independence : wayfinding systems which adapt to a visually impaired person's context

Despite an increased amount of technologies and systems designed to address the navigational requirements of the visually impaired community of approximately 7.4 million in Europe, current research has failed to sufficiently address the human issues associated to their design and use. As more types of sensing technologies are developed to facilitate visually impaired travellers for different navigational purposes (local vs. distant and indoor vs. outdoor), an effective process of synchronisation is required. This synchronisation is represented through context-aware computing, which allows contextual information to not just be sensed (like most current wayfinding systems), but also adapted, discovered and augmented. In this paper, three user studies concerning the suitability of different types of navigational information for visually impaired and sighted people are described. For such systems to be effective, human cognitive maps, models and intentions need to be the focus of further research, in order to provide information that is tailored to a user's task, situation or environment. Methodologies aimed at establishing these issues need to be demonstrated through a multidisciplinary framework

TUGS – The tactile user guidance system

The Electronic System and Information Technology Research Group at Brunel University has designed a multifaceted navigation system for blind and visually impaired pedestrians. The primary operation of the system mimics the advantages of an informed sighted guide by using Global Positioning Systems and remote (sighted on the user) video cameras as navigational sensors. The information generated is streamed to a central control centre. This allows the system to operate in a fully automatic or operator assisted mode dependent on the users requirements. Initially the system used an audio link to transfer information to the user, however this has proved problematic. Clear unimpeded access to ambient sound is vital for visually impaired and blind pedestrians, both for efficient wayfinding and safety. Any system which has a continuing dialogue with the user, for example, navigational instructions received through an audio link, interferes with the users ability to process ambient sounds. To solve this problem a novel Tactile User Guidance System (TUGS) with vibrating actuators, has been designed and experimentally tested. In this paper we present the design and experimental verification of TUGS with both visually impaired and sighted users. Although we have taken the visually impaired user as the ‘worst case scenario’ a practical ability to transfer information through the tactile sense has considerable value to other groups who may find themselves in restricted or overloaded visual or audio situations. These groups include; front line responders in the emergency services, railroad workers, pilots and remote vehicle operators