scholarly journals Online Healthcare Monitor System Based on Optical Wireless and FBG Sensors

2018 ◽  
Vol 7 (3.4) ◽  
pp. 100 ◽  
Author(s):  
Ibrahim A. Murdas ◽  
Ahmed N. Jabbar

In this work, a practical wireless optical communication system has been proposed for the purpose of monitoring the health condition of patients who are in hospital operating on the basis of the wireless communication system and fiber sensors. The suggest practical system employ a diffuse optical broadband link technique  based on laser Li-Fi the technology, Fiber Bragg grating (FBG) sensors was investigated.  The focused on optical fiber sensors (pressure and temperature) for medical applications because it’s small size, immunity to electromagnetic interferences and their suitability for remote monitoring. Fiber Bragg grating (FBG) based (blood pressure, temperature) sensors is designed and implemented using a conventional laser source, Optisystem version 15. The collected data from sensors is transmitted to main unit, the suggested system tested under different operating conditions such as , optical link distance, laser power and transmitter angles, all operating conditions was successively demonstrated. 

2016 ◽  
Vol 78 (3) ◽  
Author(s):  
Odai Falah Ameen ◽  
Marwan Hafeedh Younus ◽  
M. S. Aziz ◽  
RK Raja Ibrahim

In this work, measurement of temperature and liquid level were performed simultaneously using fiber Bragg grating (FBG) sensors. A multi-channel Fibre Interrogator with built-in ASE laser source operating around 1552 to 1568 nm was employed to record a shift in Bragg wavelength due to contribution from both temperature and hydrostatic pressure of liquid weight in the tank. Results show a linear response between liquid level and temperature readings against the shift in Bragg wavelength for liquid level up to 85 cm in height and the temperature range of 27 to 77 oC. The sensitivity of the sensor head for water level measurement is 10.57 pmcm-1, while the sensitivity for temperature measurement is 11.28 pm/oC respectively.


Author(s):  
Ruiqi Ma ◽  
Guoqing Feng ◽  
Huilong Ren ◽  
Peng Fu ◽  
Shuang Wu ◽  
...  

Hull monitoring system with Fiber Bragg Grating (FBG) sensors increasingly receives people’s attentions. However, for the ship hull monitoring, the deformation of hull girder changes a lot as is subjected to a huge temperature variation. Therefore, the compensation method with only FBG temperature self-correction is not suitable for the hull monitoring sensors because no material thermal expansion effects are reasonably included. In this paper, the new compensation method of hull monitoring FBG sensor based on the sensor theory with both FBG temperature self-correction and steel thermal expansion effects correction is studied. The coupled compensation method suitable for hull monitoring sensor is obtained by theoretical derivation. As the comparison, the coupled compensation experiment was carried out. The results show that the relative error under the temperature compensation method is large in the case of drastic strain and temperature changes, and the correction results of the tested method will be closer to the true level.


2013 ◽  
Vol 328 ◽  
pp. 193-197
Author(s):  
Si Jin Xin ◽  
Zhen Tong

The metal fatigue is an important factor to cause an accident in machine operation, so metal fatigue test is a significant procedure in manufacturing. Fiber Bragg Grating (FBG), as an innovative sensor, has been applied to the measurement of various rotating machines. In this paper, the time-frequency analysis is used to detect the fatigue feature of a titanium alloy measured by FBG sensors. Furthermore, the Hilbert-Huang transform (HHT) is more effective to observe the fatigue limit of the titanium alloy sheet, compared to the Wavelet transform (WT).


Author(s):  
Hong-Il Kim ◽  
Lae-Hyong Kang ◽  
Jae-Hung Han

Dimensional stability of the space structures, such as large telescope mirrors or metering substructures, is very important because even extremely small deformations of these structures might degrade the optical performances. Therefore, precise deformation data of the space structures according to environment change are required to design these structures correctly. Also, real-time deformation monitoring of these structures in space environment is demanded to verify whether these structures are properly designed or manufactured. FBG (fiber Bragg grating) sensors are applicable to real time monitoring of the space structure because they can be embedded onto the structures with minimal weight penalty. In this research, therefore, thermal deformation measurement system for the space structures, composed of FBG sensors for real time strain measurement and DMI (displacement measuring interferometers) for accurate specimen expansion data acquisition, is developed. Thermal strains measured by distributed FBG sensors are evaluated by the comparison with the strains obtained by highly accurate DMI.


2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Didik Puji Sutriyono

<p>The use of Fiber Bragg Grating (FBG) as Fabry – Perot filter has been successfully developed for visible light and ultraviolet spectra. The characteristic of FBG is analyzed by using computational model with Transfer Matrix Method by order 2 with the coupled mode theory. The reflectivity, length of grating and bandwidth are parameters to determine the performance of FGB with laser source of 1 mW for 250 – 350 nm, ultraviolet and 380 – 780 nm, visible light. The simulation is also carried out by various grating from 0.5 cm – 9.5 cm with increment step of 1 cm. The simulation result showed that there is the filter discrepancy for maximum peak. This design of FGB can be used as a filter. Only selected wavelength is allowed to transmit the signal until the end of the optical fiber.</p>


2022 ◽  
Vol 12 (2) ◽  
pp. 886
Author(s):  
Hun-Kook Choi ◽  
Young-Jun Jung ◽  
Bong-Ahn Yu ◽  
Jae-Hee Sung ◽  
Ik-Bu Sohn ◽  
...  

This paper demonstrates the fabrication of radiation-resistant fiber Bragg grating (FBG) sensors using infrared femtosecond laser irradiation. FBG sensors were written inside acrylate-coated fluorine-doped single-mode specialty optical fibers. We detected the Bragg resonance at 1542 nm. By controlling the irradiation conditions, we improved the signal strength coming out from the FBG sensors. A significant reduction in the Bragg wavelength shift was detected in the fabricated FBG sensors for a radiation dose up to 105 gray, indicating excellent radiation resistance capabilities. We also characterized the temperature sensitivity of the radiation-resistant FBG sensors and detected outstanding performance.


Sensors ◽  
2018 ◽  
Vol 18 (6) ◽  
pp. 1799 ◽  
Author(s):  
Yiming Zhao ◽  
Nong Zhang ◽  
Guangyao Si ◽  
Xuehua Li

Fiber Bragg grating (FBG) measuring bolts, as a useful tool to evaluate the behaviors of steel bolts in underground engineering, can be manufactured by gluing the FBG sensors inside the grooves, which are usually symmetrical cuts along the steel bolt rod. The selection of the cut shape and the glue types could perceivably affect the final supporting strength of the bolts. Unfortunately, the impact of cut shape and glue type on bolting strength is not yet clear. In this study, based on direct tension tests, full tensile load–displacement curves of rock bolts with different groove shapes were obtained and analyzed. The effects of groove shape on the bolt strength were discussed, and the stress redistribution in the cross-section of a rock bolt with different grooves was simulated using ANSYS. The results indicated that the trapezoidal groove is best for manufacturing the FBG bolt due to its low reduction of supporting strength. Four types of glues commonly used for the FBG sensors were assessed by conducting tensile tests on the mechanical testing and simulation system and the static and dynamic optical interrogators system. Using linear regression analysis, the relationship between the reflected wavelength of FBG sensors and tensile load was obtained. Practical recommendations for glue selection in engineering practice are also provided.


Sensors ◽  
2019 ◽  
Vol 19 (7) ◽  
pp. 1507 ◽  
Author(s):  
Hai-Lei Kou ◽  
Wang Li ◽  
Wang-Chun Zhang ◽  
Yuan Zhou ◽  
Xiao-Long Zhou

Glass fiber-reinforced polymer (GFRP) bolts have been widely used in some applications of grouted anchors because of the advantages of better resistance to corrosion, high strength-to-weight ratio, low electromagnetic properties, and so on. This study presents a field test to assess the feasibility of fiber Bragg grating (FBG) sensors in monitoring the stress profile of GFRP anchors during pulling test. Two GFRP anchors were fully instrumented with FBG sensors and then installed into the ground using a drilling and grouting method. To measure the stress profile along test anchors, seven bare FBG sensors were arranged in a single optical fiber and then embedded in the middle of GFRP bolts in the process of extrusion molding. The procedure for embedding bare FBG sensors into GFRP bolts is introduced first. Then, the axial forces and shear stresses that were calculated from the measurements of the FBG sensors are discussed. The field test results indicate that the embedded FBG technology was feasible to monitor the stress state of GFRP anchors during pulling.


2003 ◽  
Author(s):  
Akiyoshi Shimada ◽  
Kei Urabe ◽  
Yoshihiro Kikushima ◽  
Jun Takahashi ◽  
Kazuro Kageyama

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