399 results about "Fiber Bragg grating" patented technology

The invention discloses an electrical equipment operation state monitoring method, system and terminal, full life cycle health management of equipment is realized through multi-dimensional perception and intelligent analysis, a composite sensor network can be constructed from the level of the method, and high-frequency current, ultrahigh frequency, fiber grating temperature vibration, multi-parameter gas and acoustic sensors are integrated. Electromagnetic characteristics, mechanical states, environmental parameters and voiceprint characteristics are covered; the adaptive signal processing technology performs classification and noise reduction on multi-source data, and the three-dimensional digital twin model realizes time-space fusion of a temperature field, a vibration field, an electric field and a sound field; a lightweight space-time convolutional network is deployed to fuse a time domain waveform, a spectrogram and spatial distribution characteristics for diagnosis, and a hidden semi-Markov model and a particle filter algorithm are combined to dynamically predict the residual service life of equipment. The system architecture comprises a self-organizing sensor network with edge computing capability, a time-sensitive industrial communication network and a containerized analysis engine, and supports mixed reality visual interaction.

The invention discloses an aerial optical cable defect detection method based on multi-mode sensing fusion and related equipment, and relates to the field of data processing. The method comprises the following steps: acquiring multi-modal sensing data along an aerial optical cable through sensing equipment of different modals; performing time and space alignment processing on the distributed fiber bragg grating strain data, the acoustic emission signal data and the visual image data to obtain multi-mode time and space alignment data; extracting feature data of each mode based on the multi-mode space-time alignment data; performing fusion processing on the feature data of each modal through an attention mechanism to obtain fused feature data; determining a defect identification result of the aerial optical cable according to the fusion feature data, wherein the defect identification result comprises a defect type and a position of the defect on the optical cable; obtaining the result confidence of the defect recognition result; and generating a final optical cable defect detection result according to the result confidence. According to the invention, the problem that the current aerial optical cable defect detection has relatively large missed detection and false detection risks can be relieved.

The invention relates to the technical field of silicon waveguide and optical fiber coupling, and particularly provides an AI-based silicon waveguide-optical fiber mode field self-alignment coupling method and system, and the method comprises the steps: monitoring the strain distribution of a chip in real time through an integrated distributed fiber bragg grating array, and obtaining the light field intensity distribution of a coupling region through cooperation with a near-field optical probe array; constructing a deep space-time convolutional network, and generating a deformation compensation vector and a waveguide reconstruction parameter by an output layer; a nanofluid channel is integrated on the side wall of the waveguide, and the refractive index of liquid is adjusted through an electrowetting effect to realize dynamic broadening of a mode field; and the electrostatic driving micro-beam embedded below the waveguide adjusts the spatial pose of the waveguide according to an instruction of an output layer of the depth space-time convolutional network. The system comprises a light field intensity acquisition module, a convolutional network construction module and a spatial pose adjustment module. According to the method, real-time analysis and prediction are performed, so that system parameters are actively adjusted, and alignment precision and stability are improved.

The invention belongs to the technical field of lasers, and discloses a 9-shaped hybrid mode-locked fiber laser, which comprises a pumping source, a 2 * 2 polarization-maintaining fiber coupler, a nonlinear amplification loop mirror loop connected with the first side of the polarization-maintaining fiber coupler, and a chirp fiber Bragg grating connected with the second side of the polarization-maintaining fiber coupler, the polarization maintaining optical fiber coupler is located at the connecting position of the nonlinear amplification annular mirror loop and a linear arm of the laser resonant cavity and used for coupling laser of the nonlinear amplification annular mirror loop to the linear arm, and after being reflected by the chirp fiber bragg grating, the laser is output to the nonlinear amplification annular mirror loop through the chirp fiber bragg grating. And then the laser on the linear arm is split into two beams of light which are transmitted clockwise and anticlockwise in a loop of the nonlinear amplification annular mirror. Two passive mode locking technologies are combined, rapid and stable mode locking can be achieved, the influence of the environment on the operation state is small, the signal-to-noise ratio of output laser pulses can be increased, and ultra-short pulses with narrower pulse width can be achieved.

The invention relates to an all-fiber sub-hundred femtosecond laser based on an SESAM. The all-fiber sub-hundred femtosecond laser comprises the SESAM, a wavelength division multiplexer, a pumping source, a pumping protector, a gain fiber, a chirp fiber bragg grating, an isolator, a reflector, a compression unit and an autocorrelator. According to the invention, the chirp fiber bragg grating with the dispersion amount of 0.115 ps / nm is adopted to compensate positive dispersion in the cavity, so that mode-locked pulse with the spectral width of 23nm is realized. A transmission-type diffraction grating pair is adopted, the pulse width is compressed to 88fs, and the maximum spectral width 27nm is obtained under the dispersion of 0.00087 ps2 in a near-zero cavity. The condition that the optimal spectral bandwidth of the optimal seed source pulse based on the optical fiber chirped pulse amplification laser should be larger than 15 nm is met, and the compression pulse distortion of the amplifier is reduced. By adopting the linear cavity, the SESAM is adhered to the surface of the single-mode optical fiber patch cord for starting mode locking, so that an all-optical-fiber structure of the system is realized, and the single-mode optical fiber patch cord is suitable for industrial integrated application.

The invention belongs to the technical field of optical fiber sensing, and discloses a high-temperature-resistant and high-pressure-resistant multi-parameter integrated sensor and system based on optical fiber dislocation welding, and the sensor comprises a packaging main body, and the center of the packaging main body is provided with a center hole and a cavity which are used for accommodating a transmission optical fiber. The tail end of the transmission optical fiber is sequentially connected with a temperature detection device and a pressure / sound detection device which are positioned in the cavity; the temperature detection device comprises a fiber bragg grating; the pressure / sound detection device comprises a single-mode fiber, a multimode fiber, a first hollow capillary fiber and a second hollow capillary fiber which are connected in sequence; the axes of the first hollow capillary optical fiber and the second hollow capillary optical fiber are connected in a staggered manner to form an open structure. The pressure / sound-temperature multi-parameter composite in-situ synchronous measurement device realizes composite in-situ synchronous measurement of multiple parameters of pressure / sound-temperature, has the advantages of high temperature resistance, small size and high test precision, and has wide application prospects in the fields of aerospace, petroleum metallurgy, environmental monitoring and the like.

The invention discloses a structural health monitoring device for civil engineering. According to the technical scheme, the structural health monitoring device is characterized by comprising a multi-parameter sensing module used for collecting strain, acceleration, displacement, temperature, humidity, vibration frequency and structural surface crack image parameters of a civil engineering structure; the multi-parameter sensing module comprises a strain sensor group, an acceleration sensor group, a displacement sensor group, a temperature and humidity sensor, a vibration sensor and an image acquisition unit; the strain sensor group is composed of a plurality of fiber Bragg grating strain sensors which are installed at key stress parts of the structure in a distributed arrangement mode. According to the structural health monitoring device for civil engineering provided by the invention, by virtue of the unique multi-parameter sensing module, the advanced data processing module and the flexible and reliable data transmission module, various excellent effects are shown in the field of civil engineering structural health monitoring.

The invention relates to an energy accumulator durability test method and system, and the system comprises an extreme working condition simulation module which can achieve high-voltage, wide-temperature-range and high-frequency dynamic loading; the multi-sensor monitoring network integrates a fiber bragg grating strain sensor, a three-axis acceleration sensor and an acoustic emission sensor to realize collaborative monitoring of strain, vibration and microcracks; the intelligent control and energy recovery module is combined with a fuzzy PID and reinforcement learning algorithm, a magnetorheological fluid generator and a super capacitor bank, so that the control precision and the energy utilization rate are improved; and the data analysis and life evaluation platform accurately predicts the residual life by using an improved Bayesian network model and a real-time health index calculation module. According to the test method, a loading mode is dynamically adjusted through a real-time health index, an energy recovery strategy is optimized, and life early warning is triggered. The invention breaks through the limitation of the traditional test and provides an integrated solution.

A system and methods for monitoring internal corrosion in a compromised pipe are provided. An exemplary includes applying a reinforcement layer on an outer surface of a pipe over a defect detected in an internal surface of the pipe. A testing fiber Bragg grating (FBG) detector is mounted on the outer surface of the pipe over the defect. A reference FBG detector is mounted on the outer surface of the pipe. A difference in hoop strain between the testing FBG detector and the reference FBG detector is monitored to identify variations in wall thickness over the defect.

The invention discloses a fiber bragg grating femtosecond laser direct writing system and method based on light field regulation and control. The system comprises a femtosecond laser source, a polarization control module, a light beam expanding module, a light field modulation module, a 4f filtering imaging module, an oil immersed objective lens, a precision positioning and optical fiber clamping module, an observation module and a computer control module. The method comprises the following steps: firstly, fixing a standard single-mode optical fiber to be processed on a three-dimensional precision displacement platform; then programmable wavefront modulation is carried out on the femtosecond laser through a light field modulation module, and a multi-focus array is generated; then focusing the multi-focus array into the fiber core through an oil-immersed objective lens to realize one-time parallel inscribing of a plurality of refractive index modulation RIM regions; and finally, the computer control module controls the three-dimensional precision displacement platform to move at a constant speed in the axial direction of the optical fiber, and parallel integrated inscribing of a plurality of FBG structures is completed. According to the invention, the inscribing precision and inscribing efficiency of fiber bragg grating femtosecond laser direct writing are improved.

The invention discloses a high-temperature-resistant flame-retardant carbon fiber cable and an intelligent preparation method thereof, and relates to the technical field of power cables, and the cable is composed of a composite bearing core, a first / second electrical isolation belt, a stranded conductor, an annular composite bearing layer, a high-temperature-resistant main insulator and a low-smoke halogen-free outer sheath. The force bearing core is formed by bundling carbon fiber micro rods, elastic reset layers are arranged between the micro rods, micro-particle friction layers are formed on the outer surfaces of the micro rods, and a stable friction-rebound interface is constructed. A fire-resistant barrier, a phase change microcapsule filling layer and a fiber bragg grating can be arranged, and fire resistance, thermal peak suppression and on-line monitoring are considered. And closed-loop control of pultrusion, surface activation, coating and on-line thickness measurement / friction test is carried out in the manufacturing process. The cable can be operated at 200 DEG C for a long time and at 250 DEG C for a short time, the residual elongation is less than or equal to 0.10%, and light weight, high strength, high temperature resistance, low smoke and flame retardance are realized.

The invention discloses a fiber Bragg grating measuring instrument for internal displacement of a structure, and belongs to the technical field of geotechnical engineering, the fiber Bragg grating measuring instrument comprises an elastic rubber hose and an elastic plastic sleeve which are sleeved and attached inside and outside, the outer wall of the elastic rubber hose is circumferentially provided with a measuring optical fiber, and the measuring optical fiber extends along the axis direction of the elastic rubber hose; fiber Bragg grating strain sensors which are arranged at intervals are connected in series in the measuring optical fibers along the extension direction of the measuring optical fibers, the inner wall of the elastic plastic sleeve is circumferentially provided with accommodating grooves for embedding the measuring optical fibers, the accommodating grooves extend to the end part along the axis direction of the elastic plastic sleeve, and the number and the position of the accommodating grooves correspond to the number and the position of the measuring optical fibers. The device is simple in structure and high in automation degree, can monitor the internal displacement condition of the main body structure in real time, avoids the problem of untimely detection, and can avoid the error problem caused by the damage of the measuring optical fiber and the fiber bragg grating strain sensor in the measuring optical fiber under the protection of the elastic plastic sleeve.

The invention discloses a vernier effect and Sagnac ring-based dual-parameter optical fiber sensor, which belongs to the technical field of optical fiber sensors and comprises a broadband light source SLED (1), a coupler (2), a sensing structure A (3), a circulator (4), a sensing structure B (5) and a spectrum analyzer (6). The device comprises a first single-mode fiber (301), a polarization-maintaining photonic crystal fiber (302), a few-mode fiber (303), a fiber Bragg grating (304), a second single-mode fiber (501), a first hollow-core fiber (502) and a second hollow-core fiber (503). Parasitic interference is avoided by grinding the end face of the hollow-core optical fiber, and the reliability of the sensor is improved; two transmission peaks appear on the fiber bragg grating inscribed on the few-mode fiber through different mode numbers in the few-mode fiber, and gas concentration and temperature sensitivity of two signals can be calculated by observing drifting of the transmission peaks; an optical vernier effect can be formed through superposition of a Sagnac interferometer formed by polarization-maintaining photonic crystal fibers and an F-P interferometer formed by hollow core dislocation, and the gas concentration and the temperature sensitivity of the sensor are improved. The sensor has the characteristics of high sensitivity, wide measurement range, simple structure, small size and the like.

The invention discloses a highway pavement structure void detection system and method based on a grating array, and relates to the field of road engineering health monitoring, and the method comprises the steps: carrying out the grid division of a to-be-detected highway section, setting a detection section, scanning the detection section through a ground penetrating radar, and generating a three-dimensional density cloud picture; outputting a risk grade score of the detection section; arranging the fiber Bragg grating on the detection section according to the risk grade score to obtain an initial wavelength list and a space coordinate matrix; and acquiring the acoustic emission signal, the strain signal and the temperature signal based on the space coordinate matrix, and outputting a time-aligned strain-temperature-acoustic emission three-dimensional data packet. Through the acousto-optic coupling dynamic decoupling algorithm and risk score driven adaptive sensor layout, the precision and efficiency of highway pavement void detection are improved, the dynamic decoupling algorithm quantifies vibration interference through acoustic emission energy, and the strain measurement error is reduced.

The invention discloses a novel flexible soil pressure sensor and a manufacturing method thereof.The manufacturing method of the novel flexible soil pressure sensor mainly comprises the steps that a silane coupling agent is used for preprocessing a fiber bragg grating, and a silica gel liquid mixture is prepared; after the prepared silica gel liquid mixture is slowly poured into the middle shaft position of the soil pressure sensor mold and stopped, embedding the pretreated fiber bragg grating into a clamping groove reserved in the middle shaft of the soil pressure sensor mold, applying certain prestress to the fiber, and after the position of the fiber bragg grating is arranged, performing the pre-treatment on the fiber bragg grating to obtain a pre-treated fiber bragg grating; and continuously and slowly pouring the silica gel mixed solution to the top of the soil pressure sensor mold, curing and forming for 8 hours, and taking out the soil pressure sensor from the soil pressure sensor mold. The novel flexible soil pressure sensor prepared by the invention is a cake-shaped soil stress sensor with a cross-shaped fiber Bragg grating sensing unit, and has better repeatability and stability, higher sensitivity and better linear correlation.

The invention discloses a TGD-OFDR / OCC-BOTDR integrated multi-parameter sensing system and a working method thereof, and relates to the technical field of optical fiber sensors. The multi-parameter sensing system comprises a laser, an optical fiber coupler, an electro-optical modulator, an optical fiber circulator, an optical fiber Bragg grating, an acoustic optical modulator, an erbium-doped optical fiber amplifier, a random scrambler, a piezoelectric ceramic tube, a heating vessel, a delay optical fiber, a photoelectric balance detector, a filter and detector, a data acquisition card, a polarization controller, a direct-current power supply and a microwave source. An arbitrary waveform generator and the like. According to the invention, multiple parameters can be represented at the same time, the measuring speed is fast, and the sampling rate of the system can be effectively improved under the condition that sensing parameters are the same; the method has the advantage of high spatial resolution; the sensor has the advantages of high fusion and low cost, can realize simultaneous measurement of vibration and temperature / strain through single sensing, and is high in fusion and effective in cost control.

The invention is suitable for the technical field of intelligent welding, and provides an intelligent welding system based on real-time temperature control monitoring and a welding method thereof.The intelligent welding system comprises a process prediction module, a process execution module, a temperature sensing module, an analysis prediction module and an adjustment execution module; the process preconceiving module is used for generating process parameters and preconceiving trend data according to the workpiece data; the process execution module is used for welding according to the process parameters; the temperature sensing module is used for acquiring temperature data of a welding spot through infrared thermal imaging and a fiber bragg grating; the analysis and prediction module is used for analyzing the temperature data and the workpiece parameters, predicting the temperature trend of the welding spot and giving adjustment data; and the adjustment execution module is used for converting the adjustment data into adjusted process parameters. According to the device, the problems that fluctuation and delay are generated during regulation and control of a welding regulation and control system, and an irreversible coarsening phenomenon occurs due to the fact that the temperature of a microstructure layer is too high are solved, and the effects of predicting the temperature trend in advance and improving the dynamic adaptability are achieved.

The invention discloses a ground surface settlement and ground fracture monitoring device and method based on distributed fiber sensing (DSS) and fiber bragg grating (FBG). The device comprises a GFRP composite material substrate which stretches across a ground fracture and is fixed on a stable stratum through an anchoring structure, a distributed sensing and temperature measuring optical cable which is pre-embedded in a groove of the substrate, an FBG displacement meter which is connected through a plug-and-play interface, a static force level gauge, an osmometer and other point type sensors, and the data processing unit has the functions of multi-source data acquisition, temperature compensation, data fusion and multistage early warning. According to the method, multi-parameter, distributed and high-precision monitoring of the ground fracture development state is achieved through the steps of field investigation, substrate installation, sensor deployment, system calibration, real-time monitoring and the like. The method has the advantages of high measurement precision, strong anti-interference capability, convenient installation, low cost, capability of predicting the crack propagation trend and the like, and is suitable for long-period safety monitoring of geological disaster frequent areas such as mining areas and landslide areas.

According to the carbon dioxide concentration detection device based on optical fiber sensing and the storage monitoring system provided by the invention, the first optical fiber sensing unit with a modular structure is designed, so that the contact part of the sensitive coating and the optical fiber Bragg grating can be independently maintained and replaced, and the optical fiber reflection wavelength drift caused by the CO2 concentration change in the environment can be accurately detected. Meanwhile, a fiber bragg grating which is not covered with a CO2 sensitive coating is arranged as a reference, and wavelength drift mainly generated by environmental interference factors is detected. The influence of environmental interference factors on the wavelength drift of the CO2 optical fiber sensor can be eliminated by calculating the wavelength drift distance of the two fiber bragg gratings and combining the mathematical model of the wavelength drift distance and the CO2 concentration, and then the accurate CO2 concentration value is obtained. According to the invention, high-efficiency real-time monitoring of CO2 concentration in the geological storage process of CO2 is realized, and data accuracy and reliability are ensured. Moreover, the modular design facilitates the regular inspection and replacement of the sensor, prolongs the service life, reduces the maintenance cost, and is high in sensitivity, strong in stability, and good in maintainability.

A method and system of compensating for body deformation during image acquisition or external beam treatment includes acquiring image data of a body and peak wavelength data from a plurality of fiber Bragg gratings (FBGs) disposed on the body aligned along a predetermined coordinate system on the body, such as a cartesian coordinate system. The method further comprises detecting effective shifts of the Bragg wavelengths of the FBGs caused by body deformation during image acquisition, and controlling the movement of the body through a cavity in a scanning device and controlling the acquisition of the image data or external beam treatment during body deformation based on the effective shifts of the Bragg wavelengths of the FBGs.

A system and method for collision detection. The method comprises receiving a single optical sensor signal from a plurality of Fiber Bragg Gratings (FBGs), the plurality of FBGs being coupled to a manipulator, the plurality of FBGs distributed spaced apart from one another on the manipulator; determining at least one time-based feature from the single optical sensor signal; determining at least one frequency-based feature from the single optical sensor signal; providing the at least one time-based feature and the at least one frequency-based feature to a machine learning model; determine from an output of the machine learning model, a characteristic of a collision of the manipulator with an external object.

The invention relates to the crossing field of mechanical engineering and intelligent manufacturing, and discloses a real-time monitoring, regulating and controlling method for the manufacturing process of an automobile lightweight component. According to the method, a distributed fiber bragg grating sensing array is embedded in a mold, and a three-dimensional strain field at the flowing front edge of resin is obtained in real time; a multi-scale pore generation kinetic model is combined to perform online inversion on an unwetted area and pore distribution; and the pressure gradient and the mold temperature field of the hot press are adaptively regulated and controlled, and the flow path is dynamically corrected. The system comprises a sensing embedding module, a strain demodulation module, a pore inversion module, a regulation and control instruction generation module and a multi-zone execution module. According to the method, closed-loop precise control over the porosity being lower than 0.5% is achieved, and the consistency and reliability of the mechanical property of the component are remarkably improved.

The invention discloses an optical fiber three-dimensional force sensing calibration platform of an intrusive guide wire tip. The device is composed of an interventional medical guide wire, a four-core optical fiber, a single-mode optical fiber, a thermal diffusion coupler, a plurality of fiber Bragg gratings (FBGs), a pull and push dynamometer, a fixed supporting rod, an electric control displacement table, a sliding table and a coordinate card. The medical guide wire is a radiography guide wire, the interior of the medical guide wire is in a semi-hollow state, the four-core optical fiber is embedded into the tip end of the radiography guide wire, the FBGs are distributed on a fiber core of the four-core optical fiber, the prepared guide wire structure is fixed to a supporting rod provided with a clamp, and the pull and push dynamometer is arranged on an electric control displacement platform. Bending generated by horizontal collision of the tip end of the guide wire under the control of the motor is calibrated. The force sensor can be widely applied to medical interventional operations, and has the characteristic that the tip contact force is measurable, so that accurate detection of the contact stress of the guide wire and the blood vessel is realized, visual force feedback is formed, and the complication probability of the interventional operations is reduced. The invention relates to the technical field of novel medical devices.

The invention discloses a soil moisture content measuring device and method based on a fiber bragg grating. The soil moisture content measuring device comprises a protective shell, a signal transmitting module, an induction coil module, a wavelength detection module and a signal processing module, the induction coil module and the wavelength detection module are packaged through the protective shell; high and low frequency signals are output through the signal emission module and are transmitted to the induction coil module and the signal processing module; an induction current is generated through the induction coil module; wavelength change is detected through a wavelength detection module; wavelength information and capacitance information are processed through a signal processing module, and the soil moisture content is output; according to the invention, the problems of low accuracy, difficulty in networking, weak anti-interference performance and the like in the prior art are solved, quasi-distributed measurement of the water content of the soil body can be realized, and the system and the method are not only suitable for indoor tests, but also suitable for on-site long-term monitoring.

The utility model discloses a distributed sound wave sensing system for multi-frequency pulse modulation, and relates to the technical field of distributed sound wave sensing. The system comprises a narrow linewidth laser, an optical fiber coupler, a polarization-maintaining optical isolator, an acousto-optic modulator, a polarization-maintaining delay optical fiber, an erbium-doped optical fiber amplifier, a polarization-maintaining dense wavelength division multiplexer, an optical fiber circulator, an optical fiber Bragg grating, a piezoelectric transducer, a polarization controller, a photoelectric balance detector, a data acquisition card, an arbitrary waveform generator and the like. According to the utility model, the multi-frequency delay ring is utilized to carry out multi-frequency modulation, the frequency number of light waves is increased along with the circulation times of the light waves in the delay ring, and under the condition that the utilization of a large-bandwidth electro-optical modulator is not increased, the flexible modulation of the frequency is realized by utilizing a low-bandwidth acousto-optical modulator without being influenced by carrier frequency and sidebands of each order; the low-bandwidth acousto-optic modulator is used for frequency modulation in the multi-frequency delay ring, and compared with an electro-optical modulation or multi-acousto-optic / multi-light source modulation scheme, the modulation cost is effectively saved.

A measuring method for detecting a mechanical force acting on an object using a fiber optic sensor unit is disclosed. At least one measuring channel has a sensor fiber with a fiber Bragg grating embedded in the sensor fiber with a Bragg wavelength and a sensor detection element. The sensor fiber is fixed to the object in the area of the sensor FBG. The method includes coupling light from a light source into the sensor fiber and detecting the light reflected and / or transmitted by the sensor FBG by the sensor detection element. The light source has a wavelength-dependent intensity distribution with an edge. A wavelength change in the Bragg wavelength of the sensor FBG is determined by evaluating a measurement signal which has an intensity change in the detected light intensity of the entire light reflected by the sensor FBG and / or of the entire light transmitted by the sensor FBG.

The invention discloses a stone cultural relic crack filling slurry curing process parameter in-situ online detection method, which comprises the following steps: respectively preparing an optical fiber temperature-sensitive sensor, an optical fiber strain sensor and an optical fiber humidity-sensitive sensor by adopting an optical fiber Bragg grating, and integrally packaging each sensor to obtain a filling slurry curing process parameter detection device; a plurality of prepared filling slurry curing process parameter detection devices are adopted and are vertically placed at different height positions in the cracks of the stone cultural relics respectively, each filling slurry curing process parameter detection device is connected to a corresponding signal input end of a modulation-demodulation instrument, and when filling slurry is injected into the cracks of the stone cultural relics, the modulation-demodulation instrument is connected with the corresponding signal input end of the modulation-demodulation instrument. Drift data of center wavelengths corresponding to all sensors in all filling slurry curing process parameter detection devices are collected through a modulation-demodulation instrument and demodulated; and then demodulated data information is transmitted to a computer, and the computer calculates parameters of the filling slurry curing process at different height positions of the stone cultural relic crack.

The invention relates to the technical field of strain monitoring, and provides a jacking pipe convergence and strain monitoring method, which realizes omnibearing monitoring of a jacking pipe structure and environment by reasonably deploying a vibration sensor, a fiber grating strain gauge, a laser displacement meter and a gas and temperature and humidity sensor, and avoids the potential safety hazard of omission caused by incomplete monitoring information. Multi-dimensional data is transmitted to a processing node in real time, it is ensured that the data is accurately transmitted in the data transmission process, meanwhile, comprehensive preprocessing is conducted on the multi-dimensional data, and a solid foundation is provided for subsequent accurate analysis; the convergence strain information of the jacking pipe can be accurately generated by extracting the characteristics of the multi-dimensional data; according to the convergence strain information of the jacking pipe, the operation state of the heat distribution pipeline is scientifically evaluated and accurately predicted, early warning and visual display are carried out in time, safe and stable operation of the heat distribution pipeline is effectively guaranteed, accident risks are reduced, and economic losses and social influences are reduced.

The invention belongs to the technical field of optical fiber sensing, and particularly relates to a probe type humidity sensing multi-point measurement method and device based on optical fiber microspheres. According to the core scheme, a single-mode optical fiber and a multi-mode optical fiber are welded to form a Fabry-Perot (FP) microsphere sensing head, and a high-sensitivity FP interference cavity is constructed by controlling the curvature of microspheres on the end face of the multi-mode optical fiber and the thickness of an agarose gel film; temperature cross interference is eliminated by welding fiber bragg gratings (FBG) with different wavelengths; a 1 * N beam splitter is used for realizing multi-point sensing, and a mixed spectrum is separated through a Fourier transform (FFT) frequency domain filtering technology, so that independent demodulation of N sensing heads is realized. The probe-type humidity sensor has the advantages of compact probe-type structure, high sensitivity, accurate temperature compensation and multi-point synchronous measurement, and is suitable for accurate humidity detection in the fields of environmental monitoring, industrial control and the like.

The invention belongs to the technical field of strain sensing, and particularly relates to a high-precision strain sensor based on a hollow optical fiber, which comprises an optical fiber Fabry-Perot interference cavity, and the optical fiber Fabry-Perot interference cavity is formed by welding a section of hollow optical fiber between a first optical fiber bragg grating and a second optical fiber bragg grating; and the PDH high-precision demodulation module is used for carrying out real-time demodulation on a reflected signal of the optical fiber Fabry-Perot interference cavity and outputting a strain measurement result. The system is simple in structure and convenient to implement, the PDH demodulation technology is introduced, the change of dependent variables is monitored in real time, and integration is facilitated; the sensing degree of a strain signal is increased by utilizing the characteristics of the hollow optical fiber; the resonant cavity is stable in interference phenomenon and convenient for long-term detection; and by adopting an all-fiber optical path, the device has the advantages of high measurement precision, small size, easiness in embedding into a to-be-measured structure and the like.