It is widely known that materials exposed to the severe low earth orbit (LEO) environment undergo degradations. For the evaluation of fiber Bragg grating (FBG) sensors in the LEO environment, the reflective spectrum change and the Bragg wavelength shift of FBG sensor were measured during aging cycles simulating the LEO environment. The LEO environment was simulated by high vacuum (~10-5 Torr), ultraviolet (UV) radiation (<200nm wavelength), temperature cycling (-30°C~100°C), and atomic oxygen atmosphere (AO flux of 9.12×1014 atoms/cm2/s and kinetic energy of ~0.04 eV). FBG sensor arrays were embedded into the graphite/epoxy composite material. Through the aging cycles simulated for the LEO environment, the change in the reflective spectrums and the Bragg wavelengths from FBG sensors were investigated.
S. - O. Park, Moon, J. - B., Lee, Y. - G., Kim, C. - G., and Shantanu Bhowmik, “Usage of fiber Bragg grating sensors in low earth orbit environment”, in The 15th International Symposium on: Smart Structures and Materials & Nondestructive Evaluation and Health Monitoring, San Diego, 2008.