High-precision fiber Bragg grating se nsor demodulation instrument with wide-range dynamic scanning can effectivel y improve the measuring range of the optical fiber grating sensor.Ethernet com munication module is an...High-precision fiber Bragg grating se nsor demodulation instrument with wide-range dynamic scanning can effectivel y improve the measuring range of the optical fiber grating sensor.Ethernet com munication module is an extremely important part of the high-precision grating sensor demodulation device.Network interface based on Ethernet control chip D M9000A is used to send and receive the Bragg grating sensing pulse.The network transformer YL18-2050S is used to convert and filter the pulse from network.The transmitting and receiving program of grating demodulation,hardware circuit of Ethernet transmission interface are designed.The experimental results show that the network interface can achieve accurate and real-time transmissi on of the grating sensing information at high speed.展开更多
This dissertation aims at providing steady sensing for the shape detection of colonoscopes. The research especially deals with the key techniques of fiber bragg grating (FBG) large curvature sensor and sensor net, int...This dissertation aims at providing steady sensing for the shape detection of colonoscopes. The research especially deals with the key techniques of fiber bragg grating (FBG) large curvature sensor and sensor net, integrates the techniques of mechatronics and computer graphics, and develops real time FBG shape sensing system and incremental shape sensing system for colonoscopies.展开更多
A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line s...A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line shell monitoring system was established based on optical sensing technology. According to aluminum reduction cell heat transfer theory, the 2D slice finite element model was developed. The relationship between shell temperature and cell status was discussed. Fiber Bragg grating （FBG） was chosen as the temperature sensor in light of its unique advantages. The accuracy of designed FBG temperature sensors exceeds 2 ~C, and good repeatability was exhibited. An interrogation system with 104 sensors based on VPG （volume phase grating） filter was established. Through the long-term monitoring on running state, the status of the aluminum reduction cell, including security and fatigue life could be acquired and estimated exactly. The obtained results provide the foundation for the production status monitoring and fault diagnosis. Long-term test results show good stability and repeatability which are compatible with electrolysis process.展开更多
The improvement of the signal to noise ratio （SNR） has significant meaning to the fiber Bragg grating （FBG） sensing system. The source of the noise as well as the signal attenuation of the FBG sensing system is an...The improvement of the signal to noise ratio （SNR） has significant meaning to the fiber Bragg grating （FBG） sensing system. The source of the noise as well as the signal attenuation of the FBG sensing system is analyzed. It is found that optical noise caused by the optical return loss （ORL） is the main source of noises in the system, and the coupler is the main source of attenuation of the signal. The cause of the ORL in fiber-optic elements （such as jumper cables connector and fiber end） is presented. In addition, suggestions to optimize the fiber optical sensing network in order to improve the SNR are presented. Methods to suppress noises caused by the fiber end interfaces of FBGs, including using index-matching fluid, bending fiber p!gtails in the way mentioned in this paper and cleaving the slant angle of the fiber interfaces to be 8, all contribute to the optimized SNR. Besides, the thermo-weld method is suggested to be used for both parallel and serial FBG setups to provide a low insertion loss. The results would be a useful engineering tool to design the high SNR optical sensing system.展开更多
A 20-node fiber-grating-based wireless sensor network is proposed and experimentally demonstrated. Each sensor node is integrated with the light source, 1-3 FBG sensing probes, wavelength demodulation, and wireless co...A 20-node fiber-grating-based wireless sensor network is proposed and experimentally demonstrated. Each sensor node is integrated with the light source, 1-3 FBG sensing probes, wavelength demodulation, and wireless communication module. Via self-organized clusters and low energy adaptive clustering hierarchy （LEACH） route protocols, the sensor nodes are able to exchange sensing data with the control center, and the maximum communication radius of a sensor node is over 170m. The sensor node is battery-powered with a survival lifetime of up to 120 days at a network refresh rate of 5 minutes.展开更多
文摘High-precision fiber Bragg grating se nsor demodulation instrument with wide-range dynamic scanning can effectivel y improve the measuring range of the optical fiber grating sensor.Ethernet com munication module is an extremely important part of the high-precision grating sensor demodulation device.Network interface based on Ethernet control chip D M9000A is used to send and receive the Bragg grating sensing pulse.The network transformer YL18-2050S is used to convert and filter the pulse from network.The transmitting and receiving program of grating demodulation,hardware circuit of Ethernet transmission interface are designed.The experimental results show that the network interface can achieve accurate and real-time transmissi on of the grating sensing information at high speed.
文摘This dissertation aims at providing steady sensing for the shape detection of colonoscopes. The research especially deals with the key techniques of fiber bragg grating (FBG) large curvature sensor and sensor net, integrates the techniques of mechatronics and computer graphics, and develops real time FBG shape sensing system and incremental shape sensing system for colonoscopies.
基金Project(61174018) supported by National Natural Science Foundation, ChinaProject(ZR2011FQ025) supported by the Natural Science Foundation of Shandong Province ChinaProject(2010GN066) supported by the Independent Innovation Foundation of Shandong University, China
文摘A fiber Bragg grating temperature sensor network was designed to implement the real-time health monitoring of the aluminum reduction cell. The heat transfer process was simulated using software ANSYS, and an on-line shell monitoring system was established based on optical sensing technology. According to aluminum reduction cell heat transfer theory, the 2D slice finite element model was developed. The relationship between shell temperature and cell status was discussed. Fiber Bragg grating （FBG） was chosen as the temperature sensor in light of its unique advantages. The accuracy of designed FBG temperature sensors exceeds 2 ~C, and good repeatability was exhibited. An interrogation system with 104 sensors based on VPG （volume phase grating） filter was established. Through the long-term monitoring on running state, the status of the aluminum reduction cell, including security and fatigue life could be acquired and estimated exactly. The obtained results provide the foundation for the production status monitoring and fault diagnosis. Long-term test results show good stability and repeatability which are compatible with electrolysis process.
文摘The improvement of the signal to noise ratio （SNR） has significant meaning to the fiber Bragg grating （FBG） sensing system. The source of the noise as well as the signal attenuation of the FBG sensing system is analyzed. It is found that optical noise caused by the optical return loss （ORL） is the main source of noises in the system, and the coupler is the main source of attenuation of the signal. The cause of the ORL in fiber-optic elements （such as jumper cables connector and fiber end） is presented. In addition, suggestions to optimize the fiber optical sensing network in order to improve the SNR are presented. Methods to suppress noises caused by the fiber end interfaces of FBGs, including using index-matching fluid, bending fiber p!gtails in the way mentioned in this paper and cleaving the slant angle of the fiber interfaces to be 8, all contribute to the optimized SNR. Besides, the thermo-weld method is suggested to be used for both parallel and serial FBG setups to provide a low insertion loss. The results would be a useful engineering tool to design the high SNR optical sensing system.
文摘A 20-node fiber-grating-based wireless sensor network is proposed and experimentally demonstrated. Each sensor node is integrated with the light source, 1-3 FBG sensing probes, wavelength demodulation, and wireless communication module. Via self-organized clusters and low energy adaptive clustering hierarchy （LEACH） route protocols, the sensor nodes are able to exchange sensing data with the control center, and the maximum communication radius of a sensor node is over 170m. The sensor node is battery-powered with a survival lifetime of up to 120 days at a network refresh rate of 5 minutes.
