Experimental research on damage detecting in composite materials with FBG sensors under low frequency cycling

This paper discusses the problems associated with the use of Fiber Bragg Grating (FBG) sensors to detect internal damage to composite specimens under low frequency cycling. This work utilized FBG sensor embedded cantilever beam specimens with and without known damage. FBG sensor measurement parameters which can reflect the location and degree of damage were obtained. Finally, the results obtained from the FBG sensors were compared to theoretical strain deviations, as calculated using ANSYS, to confirm the feasibility and range of sensitivity of FBG sensors for damage monitoring of composite material specimens. The research shows that FBG sensors can be used in detecting damage in composite materials under low frequency cycling and when the FBG senor is within 15 mm of the extent of the damage is over 2 mm.