Tactile distance feedback for firefighters: design and preliminary evaluation of a sensory augmentation glove

In this paper, we describe the design and preliminary evaluation of a vibrotactile glove for distance display in low vision search contexts. Specifically, this glove was developed for firefighting applications in which users experience compromised vision due to a combination of smoke and low ambient light levels. The glove maps an ultrasonic rangefinder to a pair of vibrating motors on the dorsal surface of the hand. Initial perceptibility testing with 15 participants showed participants were consistently able to detect the presence and absence of obstacles in a gap-detection task (93% correct detection) and to detect relative changes in the proximity of an obstacle (74% correct identification of relative position). Mapping tactile stimuli to absolute position was more challenging, with an accuracy rate of 57% (adjusted to 89% within one unit of actual position). Challenges to implementation of the concept include response time-lag, challenges of absolute judgment, and width of the sensor signal cone.