Relationship between the Structure of Finger Tissue and the Location of Tactile Receptors (3rd Report, Results of Contact Analysis between a Finger and a Rough Plate)

Contact condition between a cross section of a finger and a plane plate was analyzed in our previous study. In this study, transient dynamic response of the human finger skin and strain energy distribution at the tactile receptors are calculated when the finger is in contact with sinusoidal wave representing the surface roughness of objects. Especially, the effect of epidermal ridges, velocity of the finger movement and wavelength of the sinusoidal wave on the tactile sensation are focused. FE (finite element) model using measured geometric and material properties of an actual index finger is used. The contact between the finger with/without the epidermal ridges and the sinusoidal wave moved in the tangential direction after indented in the normal direction is calculated. It is found that Meissner's corpuscles are largely in relation with the detection of surface roughness, Merkel's discs do not detect the surface roughness when the wavelength is small. It is also found that the epidermal ridges change the pattern of strain energy density near the Meissner's corpuscles.