A Wearable Pneumatic Platform to Automatically Assess Tactile Sensitivity

Sensory deficits caused by neurological disorders, i.e., loss of tactile sensitivity and/or limb proprioception, hinder object manipulation and precise movements, and ultimately lead to a significant slow-down in motor rehabilitation. Although sensory rehabilitation has been catching on more and more, current procedures for evaluating tactile sensitivity are still inefficient in terms of equipment portability, test execution time, and specific training required for healthcare personnel. While some automated tactile stimulation platforms have been developed for other applications, robotic systems designed to evaluate residual tactile sensitivity are still largely under explored. Here we propose a hand-wearable, pneumatically driven device, which exploits an air chamber to transmit contact forces to the user's fingertip by means of sliding pin, which can then be used to assess tactile sensitivity in a quantitative and reproducible manner. We tested the proposed platform on five healthy participants, and obtained pressure perception thresholds in the order of 0.01 bar, with a median of ~0.03 bar, which showed a good correlation (p = 0.8441) with the SemmesWeinstein test. Although these results are preliminary, they suggest the potential of the proposed device as a complementary assessment tool of tactile sensitivity.