| Title |
Fiber-optic Goniometer to Measure Knee Joint Angle for the Diagnosis of Gait Disturbance |
| Authors |
김선근(Kim, S.G.) ; 신상훈(Shin, S.H.) ; 전다영(Jeon, D.) ; 홍승한(Hong, S.H.) ; 심혁인(Sim, H.I.) ; 장경원(Jang, K.W.) ; 유욱재(Yoo, W.J.) ; 이봉수(Lee, B.) |
| DOI |
https://doi.org/10.5370/KIEE.2013.62.7.1009 |
| Keywords |
Fiber-optic sensor ; Goniometer ; Joint angle ; Gait disturbance ; Knee joint |
| Abstract |
In this study, we developed a fiber-optic goniometer for the continuous measurement of knee joint angle which provides important medical information on Alzheimer's disease. The fiber-optic goniometer is composed of a light-emitting diode (LED), a plastic optical fiber (POF), and a voltage output photodiode (PD). As a sensing part of the fiber-optic goniometer, a unclad fiber with regular intervals of 1 mm was fabricated to improve efficiency of bending loss according to the angle variation of knee joint. The emitting light with a center wavelength of 470 nm from a LED is guided by a POF to the PD, the transmitted light is then attenuated by the bending loss inside the bent POF. The intensity variation of the light transmitted from the POF gives rise to a change in output voltage in the fiber-optic goniometer. Therefore, we measured the real-time output voltage of the proposed fiber-optic goniometer using the unclad fiber according to the knee joint angle. Through the repeated experiments, the fiber-optic goniometer shows that it has a reversibility and a wide measurable angle range. |