Design, fabrication and testing of a 3D printed FBG pressure sensor

Abstract

In this paper, a fiber Bragg grating (FBG) pressure sensor was designed and fabricated using 3D printing method for the measurement of vertical pressure. The raw material used for the fabrication of this new pressure sensor was Polylactic Acid (PLA). The effectiveness of embedding FBG sensors inside printed PLA material was first examined taking into account different infill densities. It is found that the FBG sensor can be successfully embedded into PLA material without sacrificing its sensing performance. The change of infill density has no influence on both peak and residual wavelength change of FBG sensors during and after the printing process. All FBG sensors printed inside PLA prototype with different infill density values exhibit almost the same peak and residual wavelength rise values in the printing process. In addition, the higher the density value, the longer the time required to finish printing process. A simple FBG pressure sensor was designed and fabricated according to the successful experience of embedding FBG sensors into printed PLA. Measurement performance of this FBG pressure sensor was examined in laboratory cyclic loading tests. Calibration tests indicate that the maximum measured vertical pressure of this new pressure sensor was 2000 kPa with a measurement sensitivity of 13.22 kPa/pm.