Abstract
A method of controlling a respiratory system is proposed for the maintenance of a desired alveolar CO2-concentration with the elimination of the effect of irregular metabolic rate change. This method is based on the model matching technique under the condition that a respiratory system is only partly described by Volterra series. That is, the contribution of air ventilation rate change to alveolar CO2-concentration is regarded to be partially described by an input-output relation using finite order Volterra series; while that of metabolic rate change cannot be recognized at all. Based on such a limited knowledge of the controlled object, two kinds of control systems; one with cascade compensation and the other with feedback compensation are designed by computer-aided partial model matching technique with a given reference model. They provide a robust control against possible parameter deviation caused by the difference of individual patients, measurement error and chronic change which are characteristic in biological subsystems. That assures an application of the proposed method to a clinical control of respiration.
