Concept study of a nonlinear mechanical lung simulator

The aim of this study is to design an anatomically-oriented simulator for lung dynamics and gas exchange in the lungs; to be used for ventilator tests and especially for automated prototypes. It has to demonstrate arbitrary reactions according to specified disease patterns that are realized via respiratory mechanics models, even including nonlinearity. The simulator is a combination of piston cylinders and controlled by an FPGA based real time controller platform. This controller has standard Ethernet interfaces to PC-s, where a graphically programmed interface allows the user to change parameters and even their individual Matlab code. This concept emphasizes on gas exchange as well; by generating some specific tidal expiratory CO2 curves via a specified internal gas mixture into cylinder combinations. The architecture of an anatomically oriented lung simulator has been derived and the first components have been manufactured and tested. A control scheme has been discussed and is recently put under development. First steps towards a robust and accurate reproduction of nonlinear dynamic responses by a simulator interacting with a ventilator have been made.