Author(s):
James Robert Marston* - University of California Santa Barbara
Jack L Loomis - UCSB Psychology
Reginald G Golledge - UCSB Geography
Roberta L Klatzky - CMU Psychology
Abstract:
Purpose: We summarize the results of 4 experiments with a Personal Guidance System (Loomis, 1985) that provides blind people with navigational information. This information is presented through various displays that give the user direct perceptual information, including virtual sound, about the environment. http://www.geog.ucsb.edu/pgs/main.htm
Method: Blind people walked and navigated routes through various environments (around a city block, a park, and completely open areas). The time to reach the final waypoint and any errors were recorded. An electronic compass was used to provide the system with a person's facing or hand-pointing direction. Various outputs were evaluated, including headphones that delivered virtual sound, a haptic pointer interface that delivered information through a speaker, an ear-bud that used tone cues, and a vibrotactile device that provided on and off-course information.
Results: Virtual sound coming from headphones produced the fastest travel times and the highest ratings from users, but all participants were able to complete all experimental tasks regardless of the amount of external environmental cues available and the type of interface used. Even without virtual sound or spoken language, users found the final point just by heeding a vibration signal on the wrist. Participants also were able to seamlessly transfer from using GPS signals to another locating device. Precise locations such as a bus stop pole could be easily located. Faster travelers queried the system for directional information less often the slower or less confident participants.
