Design and Simulation of FBG Based Sensor for Positioning Guan in Pulse Diagnosis

In Traditional Chinese Medicine (TCM), the radial artery on the medial side of the radial styloid process is called Guan, where the pulse wave is felt and analyzed for diagnosis. However, most of the current research on digitalization of TCM pulse diagnosis lacks discussion of the positioning of Guan, and the existing few positioning methods also have some problems. This paper proposes a sensor structure based on FBG, which can detect the fluctuation of radial styloid process and pulse force through two contact ends, so as to determine the position of Gao Gu and radial artery, and realize the purpose of positioning Guan. The finite element simulation analysis was carried out for the designed sensor. The simulation results show that the input pressure and the input displacement are respectively proportional to the change of FBG wavelength. The displacement sensitivity of the sensor is 574.86 pm/mm, the input displacement range is
$0\sim 3\text{mm}$
, the pressure sensitivity is 1561.65 pm/N, and the input pressure range is
$0\sim 2.5\mathrm{N}$
, which can meet the needs of detecting the radial styloid process and radial artery pulse.