<XML><RECORDS><RECORD><REFERENCE_TYPE>3</REFERENCE_TYPE><REFNUM>8938</REFNUM><AUTHORS><AUTHOR>McGookin,D.K.</AUTHOR><AUTHOR>Gibbs,M.</AUTHOR><AUTHOR>Nivala,A-M.</AUTHOR><AUTHOR>Brewster,S.A.</AUTHOR></AUTHORS><YEAR>2007</YEAR><TITLE>Initial Development of a PDA Mobility Aid for Visually Impaired People</TITLE><PLACE_PUBLISHED>proceedings of INTERACT 2007</PLACE_PUBLISHED><PUBLISHER>IEEE</PUBLISHER><LABEL>McGookin:2007:8938</LABEL><ABSTRACT>We discuss requirements surrounding a mobile navigation system for visually impaired people. We describe an initial prototype based on a PDA using GPS location tracking. This prototype has so far failed to provide reliable location detection, due to the use of GPS in built up environments. We discuss how our system may improve detection by switching between a range of different location tracking technologies. However, we conclude that there may still be times when these technologies fail, and more work is needed on how to support the user in such circumstances.</ABSTRACT></RECORD></RECORDS></XML>