Development Of A Noninvasive Respiratory Airway Synchronous Open Device

Currently, artificial airway is a commonly used way to solve the problem of the breathing airway atresia in the process of critically ill patients’treatment. However, this approach may lead to a variety of side effects for patients, such as sympathetic stimulation reflex, airway injury, infection. In severe cases it may endanger life. In order to reduce the safety risks of the establishment of artificial airway for the patients, this paper proposes a solution about a non-invasive respiratory airway synchronous open device. By the non-invasive way, it will solve the problem of patient’s breathing airway atresia.Based on the analysis of various methods of airway open, this paper proposes a design scheme about a non-invasive respiratory airway synchronous open device based on jaw lifting method. The design scheme uses the method of driving mechanism reciprocating to lift the jaw and implement airway open with noninvasive. The speed of lift movement can synchronize with the patient breathing signal. This paper completed the mechanical system and monitoring system design of non-invasive respiratory airway synchronous open device.In the mechanical system design, firstly, based on the body size analysis of the head face and skull structure, the design parameters of non-invasive respiratory airway synchronous open device is determined. Then, this paper proposes a design scheme that the mandible lift mechanism contains a multi-degree of freedom. Using the 3D modeling software SolidWorks completed the virtual prototyping of non-invasive respiratory airway synchronous open device. The mechanical structure is composed of the X direction adjustment mechanism, Z direction adjustment mechanism, the sphere hinge mechanism, lift mechanism and other components. During operation, the X direction adjustment mechanism, Z direction adjustment mechanism and spherical hinge mechanism can adjust position and lock according to the different characteristics of the patient. The lift mechanism located at the end of adjustment mechanism conduct reciprocation movement by motor. Through this way, it opens the human respiratory airways. To ensure the safe use, spherical hinge uses quick-locking and release mechanism based on solenoid and pinch return spring.Using ADAMS software performs a dynamic simulation analysis to the X and Z direction adjustment mechanism and spherical hinge structure. It cleared the movement law of lifts mechanism and the situation of parts’ external force. Using ANSYS15.0 finite element software analy the stress-stain of the key structure of respiratory airway open device and verified that the structural design was reasonable.In measurement and control system design, the breathe detection and motion control system is developed based on SCM STC12C5608AD. Pressure transmitter TS-800-FY is selected as the respiratory signal measuring sensor. Current/voltage converter module is selected to convert 4-20mA current signal which pressure transmitter output, into the signal that microcontroller can be collected. Maxon EPOS224/2EC is chose as a motor drive module. It can send instructions through the microcontroller to drive motors and achieve motion control.Preliminary model tests show that the design of non-invasive respiratory airway synchronous open device is reasonable and the desired result is achieved. The research provides a viable solution to open the patient’s breathing airways with noninvasive.The research lays the foundation for non-invasive respiratory airway synchronous open device eventually into clinical trials.