| Popis: |
We describe the use of swept wavelength interferometry for millimeter resolution dynamic fiber optic strain measurements on a cyclically loaded aluminum coupon using single mode fiber. The interrogation method is based on measuring the phase along the optical fiber and correlating the change in the phase derivative to strain via calibration. This technique enabled data acquisition at 150 Hz at a 1mm spatial resolution. A maximum spatial and strain range of 8 ms and ±7,500 μe, respectively, can be obtained. Measurements of the strain profile near a notch on the coupon demonstrate the utility of the high spatial resolution made possible with this technique. |
