Voice Operated Guidance Systems for Vision Impaired People: Investigating a User-Centered Open Source Model

People who have impaired vision regularly use white canes and/or guide dogs to assist in obstacle avoidance. Guide dogs can also be of limited assistance for finding the way to a remote location, known as ??wayfinding?? Several electronic devices are currently available for providing guidance to a remote location, but these tend to be expensive, or make use of a Braille interface. This project investigated the suitability of a user centered client server approach for the development of a talking GPS system intended to fill a niche for outdoor wayfinding. The work resulted in a working prototype proof-of-concept system that uses a speech-recognition speech-synthesis interface. The prototype solution includes a custom web application which accesses the Google maps API. The system is intended to be scalable and extensible with additional features such as sensors for obstacle avoidance and access to web-based information such as weather, train or bus timetable information. The client server approach was found to be suitable for the development of this type of application

The SmartVision local navigation aid for blind and visually impaired persons

The SmartVision prototype is a small, cheap and easily wearable navigation aid for blind and visually impaired persons. Its functionality addresses global navigation for guiding the user to some destiny, and local navigation for negotiating paths, sidewalks and corridors, with avoidance of static as well as moving obstacles. Local navigation applies to both in- and outdoor situations. In this article we focus on local navigation: the detection of path borders and obstacles in front of the user and just beyond the reach of the white cane, such that the user can be assisted in centering on the path and alerted to looming hazards. Using a stereo camera worn at chest height, a portable computer in a shoulder-strapped pouch or pocket and only one earphone or small speaker, the system is inconspicuous, it is no hindrence while walking with the cane, and it does not block normal surround sounds. The vision algorithms are optimised such that the system can work at a few frames per second