Simulação de sinais de EMG e modelagem de impedância muscular no LTSpice
Data
2023-07-13
Tipo
Trabalho de conclusão de curso
Título da Revista
ISSN da Revista
Título de Volume
Resumo
Os biopotenciais são sinais elétricos produzidos
por células e tecidos vivos do corpo humano, que podem ser
medidos e analisados para fins médicos, de pesquisa ou de
diagnóstico. Esses sinais são gerados pela atividade elétrica nas
células nervosas, musculares e cardíacas, e podem ser
detectados e registrados através de eletrodos colocados na pele
ou dentro do corpo. A modelagem de circuitos é uma etapa
fundamental para obter uma boa aproximação dos parâmetros
e sinais dos biopotenciais musculares. Através da modelagem, é
possível equivaler os tecidos do corpo humano a componentes
elétricos, como resistores e capacitores, devido às propriedades
de impedância e condutividade dos tecidos. Assim, o trabalho se
baseia na utilização do software de uso livre LTSpice para
modelagem e simulação do tecido muscular e visualizar os
efeitos que o tecido com características saudáveis ou patológicas
causam em um sinal de EMG retirado de um banco de dados.
Levando em consideração como principal parâmetro o circuito
equivalente ao tecido condutor, foi possível verificar a influência
deste tanto na amplitude quanto na frequência do sinal. Com a
ausência de trabalhos que disponibilizem dados como
capacitância e resistência do tecido muscular patológicos, tais
valores foram sugeridos pelos autores e posteriormente
analisados. As simulações permitiram observar o quanto o
tecido condutor pode influenciar no sinal de EMG,
demonstrando ser uma ferramenta de aplicação de análise de
sinais biológicos para estudantes de áreas afins.
Biopotentials are electrical signals produced by living cells and tissues in the human body, which can be measured and analyzed for medical, research, or diagnostic purposes. These signals are generated by the electrical activity in nerve, muscle, and cardiac cells, and can be detected and recorded through electrodes placed on the skin or inside the body. Circuit modeling is a fundamental step in obtaining a good approximation of the parameters and signals of muscle biopotentials. Through modeling, it is possible to equate human body tissues to electrical components, such as resistors and capacitors, due to the impedance and conductivity properties of tissues. Thus, this work is based on the use of the free LTSpice software for modeling and simulation of muscle tissue and visualizing the effects that tissue with healthy or pathological characteristics cause on an EMG signal taken from a database. Taking into account as the main parameter the equivalent circuit to the conductive tissue, it was possible to verify the influence of this both on the amplitude and frequency of the signal. With the absence of works that provide data such as capacitance and resistance of pathological muscle tissue, such values were suggested by the authors and subsequently analyzed. The simulations allowed to observe how much the conductive tissue can influence the EMG signal, demonstrating to be a tool for the application of biological signal analysis for students in related areas.
Biopotentials are electrical signals produced by living cells and tissues in the human body, which can be measured and analyzed for medical, research, or diagnostic purposes. These signals are generated by the electrical activity in nerve, muscle, and cardiac cells, and can be detected and recorded through electrodes placed on the skin or inside the body. Circuit modeling is a fundamental step in obtaining a good approximation of the parameters and signals of muscle biopotentials. Through modeling, it is possible to equate human body tissues to electrical components, such as resistors and capacitors, due to the impedance and conductivity properties of tissues. Thus, this work is based on the use of the free LTSpice software for modeling and simulation of muscle tissue and visualizing the effects that tissue with healthy or pathological characteristics cause on an EMG signal taken from a database. Taking into account as the main parameter the equivalent circuit to the conductive tissue, it was possible to verify the influence of this both on the amplitude and frequency of the signal. With the absence of works that provide data such as capacitance and resistance of pathological muscle tissue, such values were suggested by the authors and subsequently analyzed. The simulations allowed to observe how much the conductive tissue can influence the EMG signal, demonstrating to be a tool for the application of biological signal analysis for students in related areas.