Real-time aircraft structural health monitoring system using fiber Bragg grating sensor

Aircraft accidents can be prevented through the use of a real-time structural health monitoring system based on a fiber Bragg grating sensor.

Article  |  Spring 2017

The Smart Structures and Composites Lab (Prof. Chun-Gon Kim, Department of Aerospace Engineering, KAIST) has developed a fiber-Bragg-grating(FBG)-sensor-based real-time aircraft structural health monitoring (SHM) system that can monitor the aircraft structural integrity during operation.

The role of aircrafts has expanded and is now established a vital mode of transportation. With the rapid increase in demand for air transportation, airlines have come to recognize the importance of aircraft safety management systems and have attempted to reduce the occurrence of aircraft accidents. Thus, nowadays, SHM systems are being actively implemented to prevent aircraft accidents.

SHM allows for the real-time monitoring of the structural conditions using various sensors installed in the major parts of aircraft structures along with the diagnosis and assessment of the structural integrity by analyzing the acquired condition data. However, previous studies encountered difficulties and limitations with regard to the applicability for in-situ monitoring of aircrafts.

FBG sensors hold numerous advantages over conventional strain gauges, including their small size, light weight, embeddability, convenient multiplexing, corrosion resistance, and electromagnetic interference immunity. Thanks to such advantageous characteristics of FBG sensors, they are suited for the multiplexed measurement of aircraft structures. Therefore, in the developed SHM system, FBG sensors were used to collect information with regard to the structural integrity of the aircraft.

The developed FBG-sensor-based monitoring system measures the flight-load and estimates the impact location in real-time. If bird strikes or abnormal loads occur during flight, the system transfers information about the event to the pilot with warnings and helps the pilot respond. During flight, various flight parameters as well as structural intensity information are recorded, and this data is configured so that authorized users can directly access the flight data. Based on data recorded during flight, it is expected that lifetime estimation of the aircraft will be possible.

The developed monitoring techniques could easily solve certain issues that may occur in the actual application of monitoring systems for in-situ aircraft wing structures, and the monitoring techniques are applicable for other vehicles or structures requiring real-time monitoring of structural conditions. Through this research, it is expected that the developed monitoring techniques will be helpful in enhancing the efficiency, safety, and reliability of aircraft operations in the near future.

An article on this research entitled “Aircraft health and usage monitoring system for in-flight strain measurement of a wing structure” was published on August 28th, 2015 in Smart Materials and Structures (http://iopscience.iop.org/article/10.1088/0964-1726/24/10/105003).