Investigation of reciprocating friction characteristics between different bionic surfaces of prosthesis materials and skin

Abstract

In this study, three types of bionic texture surfaces were designed, based on the microstructure of tree frog and gecko feet, for two typical prosthetic substrates: silicone rubber and thermoplastic polyurethane elastomer (TPU). The surface energy of all bionic texture surfaces, and the relative displacement and energy dissipation of the reciprocating friction between these bionic surfaces and skin, were investigated. The results revealed that the bionic texture of the prosthetic socket surface had an obvious influence on the surface characteristics and reciprocating characteristics of friction with the skin. According to the comprehensive weight rating method, the optimal bionic textures for the silicone rubber substrate were a regular hexagonal prism and a quadrangular prism; for the TPU substrate, only the regular quadrangular prism texture was optimal. These textures can effectively increase the surface energy of the surface of the prosthetic socket, thereby increasing its adhesion to skin and reducing the dissipation of friction energy when it interacts with the stump. This bionic prosthetic socket surface design helps improve the adaptation between the prosthetic socket and the stump.