Investigation of Single Segment Side-Polished Optical Fiber Sensor for Shoulder Joint Monitoring

Shoulder monitoring is an important stage in the diagnosis and treatment process of affected patients. Current devices available in the clinical environment for this application are focusing on flexible ruler or manual goniometer, which are prone to measurement error. Alternative approaches including accelerometer, magnetometer, strain sensor and inertial measurement unit (IMU) are subject to reading error, susceptible to output drift, has bulky overall size and difficult to be attached on the human body (via adhesive or garment). To solve this issue, this paper presents the use of an optical fiber sensor (OFS) based on intensity modulation technique via single segment side-polished fiber. Based on the experimental study, the proposed method can be utilized to measure an angle between 0deg. and 90 deg. Additional optical sensors can be added to increase the sensor’s range of motion that is sufficient for shoulder joint measurement.