Highly reliable advanced grid structures (HRAGS) for aircraft structures using multi-point FBG sensor

There is a growing demand for lightweight structures in aircraft systems for energy and cost savings. The authors have therefore continued development of the Highly Reliable Advanced Grid Structure (HRAGS) with the aim of application of the same to aircraft. HRAGS is provided with health monitoring functions that make use of Fiber Bragg Grating (FBG) sensors in advanced grid structures, which have been the focus of attention in recent years as lightweight structures. It is a new lightweight structural concept that enables lighter weight to be obtained while maintaining high reliability. This report describes the tests and evaluation of the Proto System conducted to verify experimentally the concept of the highly reliable advanced grid structure. The Proto System consists of a skin panel embedded with 29 FBG sensors and a wavelength detection system. The artificial damage to the skin panel of the specimen was successfully detected by comparing the strain distributions before and after the introduction of the damage measured by FBG sensors. Next, the application of HRAGS to the wing tip was studied. The results of the studies above are reported here.