Development of a Hydraulic Model of the Microcontrolled Human Circulatory System

Abstract

Cardiovascular diseases are the leading cause of deaths worldwide, causing more than 15.2 million deaths in 2016 alone. Thus, the need for intervention is clear so that these worrying numbers can be reversed. In this sense, a collective effort is needed in the areas of research and development of treatments for these cardiopathies. The purpose of this work is to develop a microcontrolled didactic bench that reproduces the behavior of the human circulatory system (HCS). The prototype will be able to elucidate the concepts involved in the dynamics of the flow and blood pressure of the systemic circulation. The basic elements that constitute the bench are a reservoir, a compliance chamber, a hydraulic piston pump driven by a direct current motor and a gate valve. All actuator elements and sensors are interconnected by a control system that can be accessed by a computer. The hydraulic circuit is based on the Windkessel model, which explains the transformation of the pulsatile flow of the heart into a virtually constant flow. The bench is capable of simulating scenarios of this phenomenon with parametric pressure variations between 40 and 210 mmHg and heart rate from 70 to 100 bpm. After the development of the bench, it was subjected to tests with fixed values of ejection volume and engine rotation for hypotension, normotension and hypertension, according to the norm ISO 5840-3:2013. The experimental data obtained from the bench were compared to the values ​​of the systolic and diastolic pressure ranges reported in the literature.