Abstract

The results of several studies for portable ventilators state that it is difficult to regulate oxygen levels of fraction of inspired oxygen (FiO2) that are in accordance with what is needed directly during the implementation of oxygen therapy. Some portable ventilators cannot set the FiO2, so the ventilators work with a fixed FiO2. To overcome this problem, medical oxygen with a level of 100% is lowered by mixing with free air with an oxygen content of about 40%. Mixing is carried out using a venturi with a large/wide hole that can be adjusted using a slated disk rotated by a direct current motor. The rotation control method uses Mamdani's fuzzy logic. The results of clinically lab-scale testing show that the fuzzy logic control system is able to control the average error pressure of 10.3%, better when compared to the on-off control method, which is 14.5%. The fuzzy logic method is able to increase the accuracy of FiO2 on a portable ventilator.