Development of a Fault Detection Instrument for Fiber Bragg Grating Sensing System on Airplane

Abstract

This study develops a fault detection device for the fiber Bragg grating (FBG) sensing system and a fault detection method to realize the rapid detection of the FBG sensing system on airplanes. According to the distribution of FBG sensors on airplanes, the FBG sensing system is built based on wavelength division multiplexing (WDM) and space division multiplexing (SDM) technologies. Furthermore, the hardware and software of the fault detection device and the relevant FBG demodulator are studied in detail. Additionally, in view of the similar features of the healthy FBG sensor in the same measuring point, a rapid fault diagnosis method based on a synthetical anomaly index is proposed. The features (light intensity I, signal length L, standard deviation of original sampleand energy value in time-domain P) of FBG sensors are extracted. The aggregation center value of the above feature values is obtained through the loop iteration method. Furthermore, the separation degrees of features are calculated and then form the synthetical anomaly index so as to make an effective diagnosis of the state of the FBG sensor. Finally, the designed fault detection instrument and proposed fault detection method are used to monitor the 25 FBG sensors on the airplane, the results indicated that three faulty and two abnormal FBG sensors on the airplane are identified, showing the effectiveness of the proposed fault detection method.

Fibre Bragg Grating Sensors for Condition Monitoring of High-Voltage Assets: A Review

“…To provide warning of this issue, Ref. [179] developed a fault detection for FBG sensing systems. Another consideration for wide-scale deployment is the management of data.…”

Dynamic Strain Measurement of Rotor Blades in Helicopter Flight Using Fiber Bragg Grating Sensor

“…For the commonly used germanium-doped quartz fiber, the relevant parameters are p 11 = 0.121, p 12 = 0.27, ν = 0.17, n eff = 1.456, ξ = 7.0 × 10 −6 / • C, and α = 5.0 × 10 −7 / • C. Hence, the parameter p e = 0.22 can be obtained by expression (4).…”

“…A fiber Bragg grating (FBG) sensor, as an optical signal sensor, is essentially different from a resistance strain gauge, and it has a lot of advantages such as a long-term stability, a strong corrosion resistance, a small volume, a light weight, a high sensitivity, a strong resistance to electromagnetic interference, a broad transmission band, a large communication capacity, a low transmission loss, insulation, no electric spark, small leaks, and a strong confidentiality; it has been widely used in many fields, such as: a bridge motion system for measuring the vehicle parameters based on strain measurement using FBG sensors [ 1 ], an FBG sensing application in an arch dam model test [ 2 ], and the monitoring of a coal mine roadway roof based on FBG displacement sensors [ 3 ] in the field of civil engineering; fault detection of an FBG sensing system on airplanes [ 4 ], landing-gear load measurement using a wide-range FBG strain sensor [ 5 ], border detection application via temperature, strain, and pressure using FBG [ 6 ], and FBG sensors for aircraft wing-shape measurement [ 7 ] in the field of airplane engineering; FBG data treatment aimed at eliminating the noise in the strain sensor data induced by vibrations of the helicopter blade in flight conditions [ 8 ], helicopter bearing detection technology using FBG acoustic emission technology [ 9 ], and blade vibration load characteristic measurement using FBG by the authors [ 10 ] in the field of helicopter engineering; and FBG-based acoustic emission measurement [ 11 ] and a laser self-mixing FBG sensor for acoustic emission measurement [ 12 ] for structural health monitoring.…”