Fan Hongchao

Surface Testing and Parameter Identification of Vibration

Flexible surfaces such as aircraft wings surface is easy to lead to vibration. The vibration decreases the accuracy of the precision instruments, reduces aircraft service life and is not conducive to the pilots physical and mental health. This research designed surface vibration test system based on Fiber Bragg Grating (FBG) sensor to detect surface structure of strain response curve. The frequency-spectrum curve was obtained by spectral analysis of strain response spectrum. Then the structure of natural frequencies, the damping ratios the mode of vibration and the other main parameters were identified by parameter identified method. Then the surface vibration law was obtained. Experimental results show that the fiber grating sensor test system could detect the surface vibration period, the natural frequency, the amplitude, and identify the other main parameters of surface vibration. FBG sensor speed is fast and the precision is high, however the test system is limited by frequency of the Fiber Bragg Grating demodulator.