Pham Trung Quang, Hoshi Takayuki, Tanaka Yoshihiro, Sano Akihito
Department of Engineering Physics, Electronics and Mechanics, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya, Japan.
Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
PLoS One. 2017 Dec 8;12(12):e0189293. doi: 10.1371/journal.pone.0189293. eCollection 2017.
The feeling of touch is an essential human sensation. Four types of mechanoreceptors (i.e., FA-I, SA-I, FA-II, and SA-II) in human skin signalize physical properties, such as shape, size, and texture, of an object that is touched and transmit the signal to the brain. Previous studies attempted to investigate the mechanical properties of skin microstructure and their effect on mechanoreceptors by using finite element modeling. However, very few studies have focused on the three-dimensional microstructure of dermal papillae, and this is related to that of FA-I receptors. A gap exists between conventional 2D models of dermal papillae and the natural configuration, which corresponds to a complex and uneven structure with depth. In this study, the three-dimensional microstructure of dermal papillae is modeled, and the differences between two-dimensional and three-dimensional aspects of dermal papillae on the strain energy density at receptor positions are examined. The three-dimensional microstructure has a focalizing effect and a localizing effect. Results also reveal the potential usefulness of these effects for tactile sensor design, and this may improve edge discrimination.
触觉是人类必不可少的一种感觉。人类皮肤中的四种机械感受器（即I型快适应感受器、I型慢适应感受器、II型快适应感受器和II型慢适应感受器）能将所接触物体的物理特性（如形状、大小和质地）转化为信号，并将其传递给大脑。以往的研究试图通过有限元建模来研究皮肤微观结构的力学特性及其对机械感受器的影响。然而，很少有研究关注真皮乳头的三维微观结构，而这与I型快适应感受器的结构有关。传统的真皮乳头二维模型与自然形态之间存在差距，自然形态是一种复杂且具有深度的不均匀结构。在本研究中，对真皮乳头的三维微观结构进行了建模，并研究了真皮乳头二维和三维结构在感受器位置处应变能密度方面的差异。三维微观结构具有聚焦效应和定位效应。研究结果还揭示了这些效应在触觉传感器设计中的潜在用途，这可能会改善边缘辨别能力。
