Measurement of Strain Induced by Impact with Fiber Bragg Grating
After deriving the propagation formula of stress wave through incident bar, the measured signals both in horizontal impact test and drop impact tests are investigated with novel fiber Bragg grating sensors(FBGs). Especially those strain signals from FBGs which mounted on the surface of an incident bar are studied. The signals in impactor and the FBGs embedded in the composite material under similar test condition are compared. The dropping and impacting models have been setup. The experiment data measured in a lab are analyzed both in time-domain and in frequency domain. Those ultra-high frequency components in the above strain signals can not be obtained by current FBG measurement system due to frequency limit of the demodulation system. Further study to improve the frequency of demodulation system will be done in next step.
Wei Gao, Yasuhiro Takaya, Yongsheng Gao and Michael Krystek
P. Y. Zhu et al., "Measurement of Strain Induced by Impact with Fiber Bragg Grating", Key Engineering Materials, Vols. 381-382, pp. 435-438, 2008