Nonlinear Adaptive Control of a Piston Pump Mock Ventricle

High-performance control system for a piston pump mock ventricle is developed in this research to accurately reproduce the native ventricle's pumping dynamics and to secure the physiological feasibility of the cardiovascular circulatory simulator (CCS). The challenges are that a piston pump mock ventricle has inherent parameter uncertainties of check valve resistances, high bandwidth pressure dynamics, and hard nonlinearity due to check valves. To overcome these difficulties, a nonlinear adaptive control scheme is presented in this paper. A hardware CCS is constructed based on the electrical-analog reference model of the cardiovascular circulatory system and the mathematical model of the hardware was derived using fluidic element modeling and the parameter identification experiments. The adaptive controller was designed based on the derived model. Experimental results show that the adaptive control achieved outstanding control performance in spite of the parameter uncertainties and yielded a good match with the reference model behavior. As a result, high quality elastance curve over the whole cardiac cycle was made possible at the level that has never been achieved.