Improvement of tactile sensitivity by stochastic resonance effect--applications to surgical grasping forceps.

This paper reports experimental results on a surgical grasping forceps with a vibration actuator that enhances a tactile perception ability. A short-time exposure of tactile receptors to sub-sensory white-noise vibration is known to improve perception ability. This phenomenon, called stochastic resonance (SR) in the somatosensory system, is expected to enhance the sense of touch when the weak vibration is applied to a fingertip, and thereby improve associated motor skills. A lead zirconate titanate (PZT) actuator was attached on the grip of surgical grasping forceps. A passive sensory test has been conducted for healthy subjects to confirm the efficacy of the device. Statistical significance has been observed when appropriate noise is applied. To investigate the effect of the noise intensity, a summing network of FitzHugh-Nagumo model neurons was built. The simulation results showed that a network with relatively large units can improve the detection capability of the input signal.