Fatigue damage evaluation of carbon fiber composite using aluminum foil based strain sensors

For the development of a technique for cyclic deformation assessment with the use of aluminum foil sensors (with thickness of 80 μm) glued onto the specimen surface the fatigue tests of carbon fiber reinforced composites were carried out. The DSLR camera mounted onto an optical microscope was used for capturing the images of sensors to reflect strain induced relief, which than was numerically estimated using various informative parameters (Shannon entropy, mean square error, fractal dimension and Fourier-spectrum energy) in order to obtain the cyclic deformation assessment of composite. The results are discussed in view of application of this method for the development of structural health monitoring (SHM) approach.