Fatigue damage and sensor development for aircraft structural health monitoring

It was shown by tests conducted at the National Aviation University (Kiev, Ukraine) that fatigue damage of metal structures may be estimated by sensors with the surface relief pattern to indicate the accumulated fatigue damage. The nature of the deformation relief has been investigated by the light, scan and transmission microscopy, as well as by a new nano-interferometer, developed at the National Aviation University. Fractal analysis of the surface patterns based on box-counting method has proved the efficiency of fractal geometry application for additional quantitative description of such surface structures. The evolution of deformation relief parameters on the sensors surface is determined by the process of the sensor and construction fatigue damage accumulation.