Source location using an optimized microfiber coupler sensor based on modal acoustic emission method

Abstract

Summary This paper demonstrates the application of an optimized microfiber coupler sensor (MFCS) to the source location with modal acoustic emission (MAE) method. First, based on analyzing the key influence factors of MAE method application, the package optimization of MFCS has been investigated. It is found that the best packaging length is from the groove end to the place where the 2 fibers just begin to fuse, which could achieve both, good completeness of acoustic emission signal wavelet transform and relative high sensitivity. Then, the linear source localization has been performed using the optimized MFCS. The arrival time of the acoustic emission signal is decided by the contour threshold of the wavelet transform to avoid the wave reflection from edge and mode conversion. The locating accuracy with different thresholds is analyzed. It indicates that the result agrees with the actual source position better when higher threshold is set. Furthermore, considering noise contamination and the frequency components completeness, the appropriate range of threshold is suggested to the location calculation. Finally, the favorable localization result proves that applying this optimized MFCS to the MAE source location strategy is quite feasible.

Optical Nanofiber Coupler Sensors Operating in the Cut-Off Wavelength Region

“…INTRODUCTION he fused optical fiber coupler is a relatively simple passive component, which due to its high performance and low cost, is widely exploited in telecommunications for optical power splitters, various types of interferometers, and coarse wavelength division multiplexing. In the last decade, the optical fiber coupler has been also applied to sensing applications such as pressure [1], micro fluidic flow meter [2], force [3], magnetic field [4], ultrasound [5,6] and temperature [7,8]. This optical sensor benefits from immunity to electromagnetic interference, resistance to corrosion, high sensitivity, and possibility to work in contact with flammables and explosives.…”

A Review of Microfiber-Based Temperature Sensors

“…MFCs are relatively simple passive components which, due to their high performance and low cost, are widely exploited in telecommunications for power splitters, interferometers, and coarse wavelength division multiplexing. In the last decade, optical fiber couplers have been also applied to sensing applications such as pressure [ 44 ], micro fluidic flow meter [ 45 ], force [ 46 ], magnetic field [ 47 ], ultrasound [ 48 , 49 ] and temperature [ 50 , 51 ].…”

Double-layered wrap-around sensor network for three-dimensional positioning of acoustic emission sources and its effect on monitoring crack propagation in rock samples

“…[6][7][8][9][10] In order to improve sensor efficiency, an optimized microfiber coupling sensor, the bar wave calibration method based on AE sensor, a new denoising method based on p-phase shifted fiber Bragg grating sensors, SA ultrasonic sensor were proposed to increase the sensitivity of AE sensors in terms of receiving signals and hence to improve the accuracy of location. [11][12][13][14] The aforementioned studies mostly focused on the improving AE positioning algorithm and increasing AE sensor sensitivity. However, few researches were concentrated on the optimization of AE sensor arrangement so as to improve the positioning precision of rock cracks.…”

“…6–10 In order to improve sensor efficiency, an optimized microfiber coupling sensor, the bar wave calibration method based on AE sensor, a new denoising method based on π-phase shifted fiber Bragg grating sensors, SA ultrasonic sensor were proposed to increase the sensitivity of AE sensors in terms of receiving signals and hence to improve the accuracy of location. 11–14…”