Study on Fabrication of FBG Bending Sensor based on 3D-Printed Support Unit

In recent studies, structural health monitoring has been extensively investigated using fiber Bragg grating (FBG) sensors. An FBG bending sensor that simultaneously measured strain and direction through geometric combinations of three FBG sensors was analyzed in a previous study. However, we relied on manual labor as no conventional method for manufacturing this type of sensor exists. Consequently, the fabricated sensor was inconsistent and generated increased errors; hence, a method to compensate for this inconsistency is required. In this study, a new support unit was designed and manufactured to solve this problem, and a method for fabricating an FBG bending sensor using this unit was developed. Two sets of cantilever bending experimental tests, i.e., those for bending sensors manufactured using the new method and those manufactured by hand, were performed to analyze the performance of the proposed method. The experimental results showed that the proposed method exhibited superior reproducibility and sensor fabrication performance