Mapping for wheelchair users: route navigation in urban spaces

Navigation around urban areas is often constraining for the mobility-impaired due to the fabric of the urban landscape, and there is a need to provide maps tailored to individual abilities. Barriers to effective navigation, such as slope, surface type and dropped kerbs, differ for able-bodied pedestrians and wheelchair users. This study identifies and quantifies such differences, and develops a Geographical Information Systems (GIS) network model for the creation of accessibility maps for wheelchair users. The measurement of barriers uses Digital Elevation Models, calculation of rolling resistance, and surveys in the field using hand-held GIS. A spatial database has been constructed which contains the pedestrian route network and barriers to navigation. A GIS application runs the model, providing a user-friendly interface to define and calculate routes through the pedestrian route network that take account of impedances to accessibility. The model, application and interface has been tested with wheelchair users and the route selection provides a good correspondence with patterns of route finding already established through experience. The interface and individually tailored maps generated, provide a tool suitable to assist wheelchair users new to an area; to enable better navigation for existing users, and a means for planners to consider the way in which access is restricted for wheelchair users in their designs for more inclusive urban environments.