High-Precision Flow Control for Lung Simulator

The lung simulator is essential in studying ventilation modes and improving man-machine synchronization. In this paper, a robust integral of the sign of the error (RISE) control with disturbance compensation is proposed for the flow regulation problem of the lung simulator suffering from modeling uncertainties. This controller effectively combines extended state observer (ESO) and RISE control. Disturbance is observed by ESO and compensated in a feedforward way. RISE is synthesized to suppress residual uncertainties to further improve system performance. The introduction of ESO frees RISE from the high switching gain and avoids the chattering phenomenon. The effectiveness of the controller is proved by the simulation in Matlab/Simulink, which shows that it can improve the accuracy of the lung simulator to simulate the 26 maximum expiratory flow curves recommended by the American Thoracic Society.