Design and implementation of a hybrid FLC + PID controller for pressure control of sleep devices

Sleep apnea is a breathing disorder that occurs when the airway is completely or partially blocked during sleep. Patients with sleep apnea use sleep devices while sleeping at night. Patients should use this device within the pressure range prescribed by doctors. For this reason, the quality of the pressure control of the air supplied to the patient from the sleep devices is very important. The control of this pressure is carried out by controlling the rotation speed of the blower motor in the sleep devices. In this study, PID controller, FLC and Hybrid FLC + PID Controller (HFLCPIDC) were designed to control the rotation speed of the blower motor and hence the pressure of the sleep device. The pressure value read from the pressure sensor at the output of the sleep device and the target pressure value adjusted on the touch panel of the sleep device were used as input parameters of these controllers. As a result of the experimental studies, it was observed that the sudden pressure change in the sleep device was stabilized at 504 ms with the PID controller, at 1575 ms with the FLC and at 484 ms with the HFLCPIDC. In addition, FLC and HFLCPIDC were able to balance the pressure at the output of the device more successfully than the PID controller. It is recommended to use HFLCPIDC for pressure control of sleep devices, as it both reacts very quickly to sudden pressure changes and can keep the pressure in balance in the best way.