A Finite Element Modeling Study on the Fingertip Deformation under Pressure Stimulation

Abstract

Pressure stimulus causes skin deformation and tactile sensation on the fingertip. Both theoretical approach and experimental technique may be used to investigate the relationship between the deformation and the sensation. Building an appropriate skin model is the most important step for further theoretical and experimental analysis. In this paper, a two dimensional (2D) fingertip biomechanical model employing finite element (FE) method is proposed based on the physiological structure of skin. With biomechanical and electrophysiological simulations, the predicted distributions of the strain energy density (SED) and the stress/strain are obtained. The relation between the predicted biomechanical responses of the subcutaneous tissue and the discharged rate reported in the literatures are investigated. The results show that the soft tissues of fingertips are very sensitive to the external stimulus, and the spatial distribution characteristics of SED within soft tissues can explain the evoked charging rate of mechanoreceptors effectively. The simulation data of the proposed FE model is highly consistent with the verified data.