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A glove developed by researchers at the Georgia Institute of Technology improves the human sense of touch using a concept called stochastic resonance. That concept, adding a bit of white noise to a person’s sensory signals, has been shown to improve sight, hearing, balance, and touch, but this is the first wearable device that implements the concept.
The glove surrounds the tip of the index finger with a pair of actuators made of layers of lead zirconate titanate. These layers of piezoelectric material generate high-frequency vibrations when electric signals are applied. The palm side of the glove that covers the finger is left alone so the person wearing the glove can manipulate objects.
In tests, researchers applied vibrations ranging from 0 to 150% of the glove wearers’ vibration amplitude thresholds. That is the level at which the wearer can just begin to feel the actuators vibrating. Test subjects then carried out standard sensory and motor-skill tasks, including two-point discrimination, single-point touch, texture discrimination, and grasp tests. The subjects performed statistically better on all tests when vibrations were applied. In the single-point touch test, for example, subjects reported whether they could feel a filament placed on the fingertip. With vibrational stimuli, subjects could detect lighter-weight filaments.
In the future, such devices might be used to restore tactile senses to people with peripheral nerve damage. They could also aid individuals with jobs that require skills in manipulation or texture discrimination.