User-centred design in the development of a navigational aid for blind travellers

Modem technology can assist disabled people in two ways: either technology can be used to design devices specifically to meet the needs of disabled people, or technology that is already used by able-bodied people can be adapted to become usable by disabled people. This paper presents an example of the former. The MoBIC (Mobility of Blind People Interacting with Computers) project is developing a new navigational aid which gives blind travellers navigational information based on the new technologies of geographical information systems (GIS) and the global positioning system (GPS) of satellites. The aid includes two components: a pre-journey planning system and a system which will assist travellers on journeys. The process by which initial prototypes for the system were developed is outlined and the elicitation of user requirements is discussed. Some results of initial evaluations conducted in the United Kingdom and the first field trials conducted in Germany are also presented.