Numerical Modelling of Capacitive Electrodes for Biomedical Signals Measurement

Surface electromyography (sEMG) uses noninvasive technique of measuring muscle action potentials on the skin surface. Numerical methods are often the first step in such a process of electrodes and biomedical electronic systems design. Thoughtful simulation, that precedes physical implementation, may speed up the product development, foreseeing its potential deficiencies in the earliest phase. Familiarisation with all the possibilities of such platforms and considerate model design in distinctively defined steps is the key to time, memory, processing power and money savings. The goal of this research is to explore the impact of the size and shape of capacitive electrode on the quality of capacitive coupling. For this purpose, the COMSOL Multiphysics software is used. In the past thirty years, a considerable number of papers have been dedicated to the implementation of various biceps muscle anatomy approximations. The primary issue of such finite element method models are realistic representations of the generation of action potentials in muscle units and their propagation through tissues and skin. In this paper, a concentric cylinder model of upper arm is proposed in order to allow stationary analysis of electrical field distribution on the electrode-fabric interface based on multiple parameters, such as electrode shape and distance or thickness and dielectric permittivity of fabric.