The Mechanical Property of the Coiled Axon of Meissner Corpuscles for Human Tactile Sensing and its Application to a Biomimetic Tactile Sensor with a Helical Structure

In this paper, we investigate the roles of helical nerve axons of Meissner corpuscles, one of the mechanoreceptors for human tactile sensation. Two properties of the coiled structure for detecting the mechanical deformation of an elastic skin are shown. Firstly, the coiled structure has a property of transforming of shear and stretch deformations of the elastic skin into stretch and shear deformations of the surface of the line of the coil. In essence, stretch and shear deformations are tranposed by the coiled structure. Thus, the transducers on the surface of the line of the coil can separately detect stretch and shear deformation of the elastic skin. Secondly, the impedance of the coiled structure is much smaller than the impedance of the line of the coil itself. Therefore, the impedance of the sensory structure can be matched to the impedance of the elastic skin. Based on these two properties of the coiled nerve structure of the Meissner corpuscles, biomimetic coiled tactile sensor is proposed.