Evaluation of orientation interfaces for wearable computers

The authors employed wearable technology in the development of an orientation aid for people with severe visual impairment. These people need a means of remaining oriented to their environment as they work their way along using their cane or dog guide. A wearable computer was used as the base for evaluating three novel orientation interfaces that resulted from the suggestions of 20 subjects in a previous study. These were: a virtual sound beacon, digitized speech, and a tapping interface. Street crossing was used as a critical orientation situation for interface testing. Significant results were: 1) the tapping interface was usable by all under all conditions, 2) speech was sometimes confusing and not always usable, and 3) the virtual beacons were preferred by many for many situations, but were not usable in very noisy environments or by people with hearing impairments in one or both ears. Investigators concluded the best interface may be one that combines tactile cues with an improved speech output format.