Design and Implementation of a Bi-level Positive Airway Pressure Control System

• Main Authors: Chih-Sung Chen, 陳志松
• Other Authors: 蔡清池
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/99236569453414021102

碩士 === 國立中興大學 === 電機工程學系所 === 95 === This paper presents a two degree-of-freedom control method for achieving bi-level positive airway pressure （Bi-PAP）of an obstructive sleep apnea (OSA) treatment system. A closed-loop DC brushless motor together with a blower and an airway module is controlled by a PI controller and then implemented using a microchip (dsPIC30F3010). With this closed-loop airway controlled module, a mathematical model of the overall open-loop system is established based on the input-output data and its system parameters are sequentially determined using the recursive least-squares (RLS) approach. A two degree-of-freedom (DOF) controller, including a nonlinear feedforward controller and a gain scheduling proportional-integral-derivative (PID) feedback controller is proposed to follow the desired bi-level pressure setpoints. Human breathing periods, including inhalation and exhalation, are estimated in order to automatically provide appropriate inhalation time for the patient. Through experimental results, the proposed control method is shown useful in achieving bi-level airway pressure tracking.