Electrical modeling of respiratory system and identification of two common COPD diseases through stability analysis technique

摘要

This paper proposes an electrical model of the respiratory system for the diagnosis of very common ventilatory diseases, like bronchitis and emphysema, under chronic obstructive pulmonary disease (COPD). Here we have developed an electrical model which is analogous to the physiological structure of the human respiratory system. The model comprises of passive electrical components (R, L and C). The input impedance is derived from the electrical model. Different time-domain responses are observed from the impedance to study the respiratory tract and alveoli conditions for qualitative assessment of bronchitis (due to narrowed bronchial tubes) and emphysema (due to air pollutants, smoking etc.) respectively. For each of the diseases, we have considered its different qualitative stages or levels e.g. average, good and poor for productive analysis. Finally, from the stability point of view, the root locus technique has been incorporated to monitor the condition of the affected respiratory system. These root locus plots also support the expected clinical phenomena from respiratory system for healthy and COPD affected subjects.