Application of fibre Bragg grating sensors for structural health monitoring of an adaptive wing

This paper presents the concept of application of fibre Bragg grating (FBG) sensors for structural health monitoring (SHM) of an adaptive wing. In this concept, the shape of the wing is controlled and altered due to the wing design and the use of integrated shape memory alloy (SMA) actuators. FBG sensors are great tools for controlling the condition of composite structures due to their immunity to electromagnetic fields as well as their small size and weight. They can be mounted onto the surface or embedded into the wing skin without any significant influence on the wing strength. In the first part of the paper a determination of the twisting moments produced by activation of the SMA actuators is presented. As a first step, a numerical analysis using a finite element method (FEM) commercial code ABAQUS (R) is presented. Then a comparison between strain values measured by FBG sensors and determined numerically is used for determination of the real value of the activation moment of every SMA actuator. Two types of damage scenarios are analysed and discussed in the paper. The first scenario is reduction of the twisting moment values produced by one of the SMA actuators. The second scenario is outer skin damage. In both damage scenarios, a neural network is used for damage detection and localization.