Improving reverse geocoding: Localization of blind pedestrians using conversational UI

Geolocation services suffer from low precision in urban environments mainly due to sky occlusion and signal reflections from buildings, which is the key disadvantage of current navigation assistive aids for blind pedestrians. We designed a method that improves reverse geocoding to the level, at which the system can differentiate sides of the street where the blind user is traveling. By implementing a conversational user interface to ask the user about important landmarks and in combination with coarse location and heading, we achieved a usable, accessible and acceptable solution. The number of address points candidates can be reduced by 50 % to those on the corresponding side of the street. A qualitative field study with six visually impaired participants confirmed acceptance by the user group and accessibility and usability of the method.