Identification of Fluidic Element Models to Simulate the Short-Term Baroreflex

Mathematical models of two fluidic elements, a centrifugal pump and an electrical controlled proportional valve, have been developed to simulate the short-term baroreflex of the cardiovascular system in the mock circulatory system. A black-box modeling technique was used to identify the pressure-flow relationships for the fluidic elements through least-squares fit to the experimental data. A two-stage regression analysis was applied to the data to identify the model structures and the corresponding parameters. Both models performed well with errors less than 5% in identification and validation tests. Performance of the models in producing control commands in terms of pump speed and valve gap was also evaluated. Both models were able to specify pump speed and valve gap accurately with a small error less than 3% in response to the cardiac output and systemic resistance output of the baroreflex algorithm. These models will be used as part of the control algorithm in a mock circulatory system to simulate the baroreflex for arterial blood pressure regulation