A CALIBRATION APPROACH FOR SMART STRUCTURES USING EMBEDDED SENSORS

This paper has presented an overview of fiber-optics technology, sensors, and interferometric sensing systems. The potential use of fiber optics either continuous (distributed) or segmented (quasi-distributed) has the potential for use as embedded sensors in 'smart-structures/skins' made of composites. Mechanical stress and strain can be correlated to fiber-optic indications. For continuous fibers, the indicated stress or strain is averaged over the embedded fiber length. Strains at discrete points can best be measured using embedded fibers which are segmented and contain initial gaps of equal length. A segmented fiber with a misalignment will show a change in γ (wavelength). If the fiber rotates and the distance between the fiber remains constant there will apparently be no change in γ. The separation of the segment coupling coefficient will be the axial strain indicator.