主被动一体式模拟肺设计与测试

Artificial lung simulator is an indispensable key instrument for ventilators' design, development and performance testing. Currently, most lung simulators are passive models at home and abroad, simulating only the passive respiratory function of the human body without autonomous respiratory consciousness and with fixed respiratory mechanical parameters. To solve the above problems, an integrated active-passive lung simulator with continuously adjustable respiratory mechanical parameter was designed in this paper. Firstly, the shape structure of the artificial lung simulator was designed and processed, and the lung simulator driving system based on a stepping motor was developed. Secondly, a LabVIEW-based upper computer control software was designed for the drive control of the stepper motor and the feedback processing of the pressure and flow signals. Finally, an overall experimental platform was built to simulate three basic human breathing modes, namely, fast breathing, calm breathing, and deep breathing for active breathing mode, showing the error within 0.05% between the measured tidal volume and the target tidal volume. And then, a lung simulator compliance control method was designed based on the PID control to achieve the following control under different compliance of passive breathing mode and maintaining the error of target compliance within 15%.