Geoscience Reference
In-Depth Information
reported by end-users, can be linked to a location in the network as estab-
lished by the attributes cataloged in the localized gazetteer, and presented
on an existing base map or in an assistive technology environment. For
mobile applications, a vision-impaired pedestrian with a Geographic In-
formation System (GIS) and a Global Positioning System (GPS)-enabled
assistive device can receive an alert or warning about proximity to reported
obstacles. This warning might include other information, such as alternative
paths and relative directions to proceed, also referenced through the local-
ized gazetteer. This research provides insight into challenges associated
with integrating user-contributed geospatial information into a comprehen-
sive system for use by the blind or vision-impaired.
1- Background and Objectives
The International Cartographic Association (ICA) Commission on Maps
and Graphics for the Blind and Vision-Impaired People has been an impor-
tant outlet for publication associated with tactile map production and use.
Many papers focus on design, production, and evaluation (i.e., Tatham
1991, Eriksson 2001, and Perkins 2001) while a few others focus more
broadly on issues such as standardization (Tatham 2001) and assistive geo-
technology (Coulson et al. 1991). In Coulson et al, the authors emphasize
that existing geotechnology can be used to automate the production of tac-
tile maps. This is an important starting point, because assistive environ-
ments that can quickly and automatically incorporate additions and
changes to an environment are particularly useful for individuals navigat-
ing through space. Transitory obstacles that present a hazard or barrier to
navigation are a distinct challenge, because they generally appear as un-
planned events and cannot generally be depicted with a standard tactile
map environment, where updates may take several days or perhaps weeks.
Because hazards and obstacles appear and change often, it is important
to use sources of data that are frequently contributed and have temporal
relevance.
Dr. Michael Goodchild, in his 2009 keynote address to the Association of
American Geographers (AAG), described the value of user-contributed or
volunteered geographic information (VGI), citing two of the most impor-
tant aspects 1) its leveraging local geographic expertise for wider purposes
and 2) its temporal relevance (2009a). Goodchild developed the concept of
user-contributed geographic information and identified it as an important
