Emergency situations such as trying to escape heavy smoke from fire could leave the sense of touch as the only way to find an exit. Rather than trying to look at a smartphone screen, a smartwatch — alerted by the same alarms — begins “speaking” through the wearer’s skin, giving directions with coded vibrations, squeezes, and tugs with meanings as clear as spoken words. In other scenarios, a surgeon or a pilot might find it useful to have another channel of communication.
This technology has been developed using haptic sense to interact with technology such as robots, prosthetic limbs, or stroke rehabilitation software. Since skin covers the entire body and has many kinds of receptors in it, the skin is an underutilized channel of information.
Soft, wearable devices were developed that allow direct touch-based communications from nearby robots, bypassing visual clutter and noise to quickly and clearly communicate. These wearable devices could be part of a uniform like a sleeve, glove, watch-band, or belt. By delivering a range of haptic cues — like a hard or soft squeeze, or a stretch of the skin in a particular direction and place, it may be possible to build a significant “vocabulary” of sensations that carry specific meanings. For example, the technology would allow people to feel the robots around them and clearly understand what the robots are about to do and where they are about to be.
Demonstrations showed that users needed less than two hours of training to learn to “feel” most words that were transmitted by a haptic armband. The Multisensory Interface of Stretch, Squeeze, and Integrated Vibrotactile Elements (MISSIVE) consists of two bands that fit around the upper arm. One of these can gently squeeze like a blood-pressure cuff and can also slightly stretch or tug the skin in one direction. The second band has vibrotactile motors — the same vibrating alarms used in most cellphones — at the front, back, left, and right sides of the arm.
Using these cues in combination, a vocabulary of 23 of the most common vocal sounds for English speakers was created. These sounds, called phonemes, are used in combination to make words; for example, the words “ouch” and “chow” contain the same two phonemes — ow and ch — in different order. Communicating with phonemes is faster than spelling words letter by letter, and subjects don’t need to know how a word is spelled — only how it’s pronounced.