System complex bio inspired – Mathematical modeling of human skin via Bond Graph

Abstract

This work describes a mathematical modelling proposal of the interaction between human skin and needle during the perforation, in order to analyze the parameters and responses of the system. The methodology employed was the selection of the thoracic region of the body, since the skin presents mechanical properties that can vary according to the region of the body and shows a non-linear behavior. Most of the perforations occur in this region. To measure the mechanical properties of the skin and variables inherent in the model by means of a mathematical representation able to simulate the deformations that occur during the process, we use the Bond Graph technique, a unified representation of dynamical systems. The results obtained provide a dynamic analysis of the variables interference in the system – what makes it possible to obtain the model due to the need to develop a prototype similar to human skin with such dynamic features for testing with needles. It is concluded that the unit impulse response and the response with initial conditions of the system modeled by Bond Graph is a system bound input bound output. However, the actual parameters of human skin were considered a limitation, which contributes to assign errors to the responses obtained, which is also a function of the modeling method adopted, since as verified, there are certain differences between the final matrix obtained by different methods.

Keywords: modeling, skin, Bond Graph.