<div style="text-align:justify;"> An in-fiber axial micro-strain sensor based on a Few Mode Fiber Bragg Grating (FM-FBG) is proposed and experimentally characterized. This FM-FBG is in inscribed in a m...<div style="text-align:justify;"> An in-fiber axial micro-strain sensor based on a Few Mode Fiber Bragg Grating (FM-FBG) is proposed and experimentally characterized. This FM-FBG is in inscribed in a multi-layer few-mode fiber (ML-FMF), and could acquire the change of the axial strain along fibers, which depends on the transmission dips. On account of the distinct dual-mode property, a good stability of this sensor is realized. The two transmission dips could have the different sensing behaviors. Both the propagation characteristics and operation principle of such a sensor are demonstrated in detail. High sensitivity of the FM-FBG, ~4 pm/με and ~4.5 pm/με within the range of 0 με - 1456 με, is experimentally achieved. FM-FBGs could be easily scattered along one fiber. So this sensor may have a great potential of being used in sensor networks. </div>展开更多
The deformation and reconstruction of the composite propeller under the static load in the laboratory is studied so as to provide the basic research for the deformation and reconstruction of the underwater deformed pr...The deformation and reconstruction of the composite propeller under the static load in the laboratory is studied so as to provide the basic research for the deformation and reconstruction of the underwater deformed propeller.The fiber Bragg grating(FBG)sensor is proposed to be used for strain monitoring and deformation reconstruction of the carbon fiber reinforced polymer(CFRP)propeller,and a reconstruction algorithm of structural curvature deformation of the CFRP propeller based on strain information is presented.The reconstruction algorithm is verified by using variable-thickness CFRP laminates in the finite element software.The results show that the relative error of the reconstruction algorithm is within 8%.Then,an experimental system of strain monitoring and deformation reconstruction for the CFRP propeller based on the FBG sensor network is built.The propeller blade is loaded in the form of the cantilever beam,and the blade deformation is reconstructed by the strain measured by the FBG sensor network.Compared with the blade deformation measured by three coordinate scanners,the reconstruction relative error is within 15%.展开更多
文摘<div style="text-align:justify;"> An in-fiber axial micro-strain sensor based on a Few Mode Fiber Bragg Grating (FM-FBG) is proposed and experimentally characterized. This FM-FBG is in inscribed in a multi-layer few-mode fiber (ML-FMF), and could acquire the change of the axial strain along fibers, which depends on the transmission dips. On account of the distinct dual-mode property, a good stability of this sensor is realized. The two transmission dips could have the different sensing behaviors. Both the propagation characteristics and operation principle of such a sensor are demonstrated in detail. High sensitivity of the FM-FBG, ~4 pm/με and ~4.5 pm/με within the range of 0 με - 1456 με, is experimentally achieved. FM-FBGs could be easily scattered along one fiber. So this sensor may have a great potential of being used in sensor networks. </div>
基金The authors are grateful for the financial support from the National Natural Science Foundation of China(NSFC)(Grant No.51775400).
文摘The deformation and reconstruction of the composite propeller under the static load in the laboratory is studied so as to provide the basic research for the deformation and reconstruction of the underwater deformed propeller.The fiber Bragg grating(FBG)sensor is proposed to be used for strain monitoring and deformation reconstruction of the carbon fiber reinforced polymer(CFRP)propeller,and a reconstruction algorithm of structural curvature deformation of the CFRP propeller based on strain information is presented.The reconstruction algorithm is verified by using variable-thickness CFRP laminates in the finite element software.The results show that the relative error of the reconstruction algorithm is within 8%.Then,an experimental system of strain monitoring and deformation reconstruction for the CFRP propeller based on the FBG sensor network is built.The propeller blade is loaded in the form of the cantilever beam,and the blade deformation is reconstructed by the strain measured by the FBG sensor network.Compared with the blade deformation measured by three coordinate scanners,the reconstruction relative error is within 15%.