Influence of indentation test factors on the mechanical response of the skin

Abstract

This study proposes in vivo tests and design of experiments to determine the influence of experimental factors on the mechanical response of the soft tissue. The experimental factors considered are: room temperature (A), indentation velocity (B), indenter temperature (C), pump pressure (D) and muscle activation (E). An inverse method was developed to obtain the constants for constitutive equations of a multilayer biological model (skin, hypodermis, and muscle) through the use of indentation tests in combination with a finite element method. For each combination of the experimental factors, two groups of constants were established from the inverse method. Sixteen combinations of experimental conditions and their corresponding constants for the Mooney-Rivlin constitutive equations were obtained to be used in further numerical models. The factor D and factor interactions ADE, CDE, and ACDE were statistically significant with respect to skin mechanical response. Therefore, it can be concluded that there is not a current equation able to represent the mechanical properties of the skin under all the experimental conditions considered in this study.

An inverse method for elastic constants identification of two-layer hyperelastic bodies with suction loading

“…The difference between the measured displacements and the displacements from the FE model were minimized through the inverse FE method to identify material parameters of the reduced polynomial hyperelastic model for each layer. Isaza et al (2019) 14 employed a combination of indentation tests and inverse FE method to characterize mechanical behavior of skin as a two-layer hyperelastic material. The indentation test was simulated in the ABAQUS FE software and by comparing the force-displacement curves obtained from experiments and simulations, the material parameters of the Mooney-Rivlin hyperelastic model were calculated for each layer.…”

Multidimensional outline of experimental techniques for human skin tribology: A scoping review

“…Depending on the anatomical region, nature of test specimen, and objective of study, the following testing techniques for mechanical properties of human skin is reported in literature such as indentation, [7][8][9][10][11] suction, 12 optical coherence tomography (OCT) 13 etc.…”