Application Of Fiber Bragg Grating Sensors In Health Monitoring

Compared to traditional sensor，the sensor based on fiber Bragg grating (FBG) havemany advantages such as light weight, small size, high sensitivity, immunity toelectromagnetic interference, resistance to corrosion and easy to build sensor network.Therefore FBG-based sensors are widely applied. With the gradual improvement of people’sliving standards and increasing of the medical conditions, the problem of aging populationbecome more serious and many countries have entered or are about to enter an aging society.The aging population is becoming a global social and economic challenge. Therefore, it isvery important if we can monitor the health status of the aging population real time andmake the appropriate intervention timely by using the optical fiber sensing technology,which can improve the quality of life and save health care resources.The main content of this paper is the application of FBG sensors in medical and healthmonitoring. This thesis contains the following two main contents：(1) A sleep quality real time monitoring system based on FBG is designed andimplemented. A new optical fiber grating pressure sensor structure is designed based on theprinciple of flat diaphragm sensitizing. The proposed scheme achieves a high sensitivitysense of the pressure. Secondly, wavelength division multiplexing (WDM) technique isutilized to form the sensor network on the basis of combining20FBGs with different peakwavelength. Fiber grating sensor demodulation instrument (Micron Optics SM-125) is usedto achieve a frequency of2Hz data collection and then connected to the computer, so thehardware architecture of the sleep quality monitoring system is completed. Finally, by usingLabVIEW program modules for real-time analysis and computing of the collectedexperimental data, the sleep quality real time monitoring system with two functions ofmonitoring times of turnover per unit time and the sleep position are realized.(2) The second part is designed to measure the frequency of respiratory system.Because breathing will produce a corresponding change in the body according to the law ofthe chest circumference, we make a wearable fiber grating strain sensor with a simplestructure. Then the measured data is analyzed and processed in time domain. By theverification of experiment, we achieve a rapid and accurate measurement of the frequency ofhuman respiration, a maximum120breathing can be measured within a minute.