339 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 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 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 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 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 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.

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 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.

The invention discloses a closed-loop system for icing state recognition and sound wave ice melting control and a method thereof, and relates to the technical field of icing monitoring and ice melting control. The system has a detection mode and an ice melting mode, can output a frequency response signal in the detection mode, and can output a sound wave vibration signal to be applied to the surface of a structure in the ice melting mode; acquiring a structural strain time sequence and outputting a current strain value through the arranged fiber bragg grating; parameters such as temperature, humidity and air are input; deploying a multi-source feature fusion and domain adaptive recognition model FCD-Net, and performing intelligent classification on icing states; outputting excitation control signals of different power levels according to the identification result; and the ice melting effect is monitored, output is controlled to be terminated, and whole-process closed-loop control is formed. According to the invention, intelligent icing identification and self-adaptive ice melting control of structures such as a power transmission conductor can be realized, and the method has the advantages of high identification precision, low energy consumption, timely response and the like, and is suitable for anti-icing application in multiple fields such as electric power, wind power and communication.

The invention relates to the technical field of sensors, and discloses a decoupling method of a temperature and pressure sensor, and the sensor comprises an F-P resonant cavity and a pressure sensing diaphragm with a fiber bragg grating. The method comprises the following steps: S1, transmitting a wide spectrum signal to a sensor, and collecting a reflection spectrum of the sensor; s2, performing baseline correction and noise reduction processing on the reflection spectrum, and extracting characteristic parameters; s3, if the characteristic parameters exceed the preset range, failure early warning is carried out; establishing and substituting the characteristic parameters into a physical model, performing multi-parameter optimal estimation, and outputting temperature and static pressure; and S4, if the characteristic parameters exceed the preset range, failure early warning is carried out. In order to enable failure early warning to be more accurate, the scheme can be adjusted to monitor the characteristic parameters extracted in the step S2 in real time, and the scheme is not limited to fixed nodes. According to the invention, intrinsic decoupling is realized, the measurement precision, the decoupling efficiency and the intelligent degree are greatly improved, the practicability is high, meanwhile, the self-diagnosis function is realized, and the reliability is ensured.

A temperature self-compensation interventional optical fiber pressure guidewire includes: a first guidewire section, a second guidewire section, and a third guidewire section that are arranged in sequence and are hollow, and a fiber bragg grating (FBG)-Fabry-Perot (FP) cascaded optical fiber sensor. The first guidewire section is configured to guide the second guidewire section and the third guidewire section in a blood vessel; the second guidewire section and the third guidewire section are internally hollow and are communicated to each other. The FBG-FP cascaded optical fiber sensor is arranged inside the second guidewire section and extends towards an inside of the third guidewire section. The FBG-FP cascaded optical fiber sensor is configured to simultaneously measure a temperature signal and a pressure signal inside the blood vessel. The present invention is particularly applicable to measuring parameters of a region before and after stenosis inside the blood vessel.

The invention relates to the technical field of optical fiber sensing, and provides a coefficient compensation device and method for correcting Brillouin gain spectrum distortion of a BOTDA (Brillouin Optical Time Domain Analysis). The compensation device comprises a laser and a coupler, the probe light branch optical path emits probe light into the sensing optical fiber, the pump branch optical path emits pump light into the sensing optical fiber, a stimulated Brillouin scattering effect is generated in the sensing optical fiber, and a probe light signal carrying Brillouin scattering information is obtained; the optical fiber Bragg grating filters an incoming detection light signal to obtain a first single side band signal; the detector converts the first single side band signal into a Brillouin scattering signal and inputs the Brillouin scattering signal into the processing module; the industrial personal computer is used for acquiring power fluctuation characteristics of the probe light under different frequencies when the coefficient compensation device does not generate the stimulated Brillouin scattering effect so as to calculate a compensation coefficient; and when the stimulated Brillouin scattering effect occurs, compensating the Brillouin scattering signal output by the detector by using the compensation coefficient to obtain the compensated Brillouin scattering signal.

The utility model discloses force and vibration integrated monitoring equipment, which comprises a monitoring fence and a monitoring host, and is characterized in that the monitoring fence comprises a force and vibration sensing unit and a fence main body, the force and vibration sensing unit comprises a weak fiber grating and a plurality of stress sensors, and the fence main body comprises a vibration monitoring main body and a stress monitoring main body; the vibration monitoring main body is arranged below the stress monitoring main body, the weak fiber bragg grating is arranged on the vibration monitoring main body, and the plurality of stress sensors are respectively fixed on the stress monitoring main body; the weak fiber bragg grating is connected with the monitoring host after sequentially penetrating through the plurality of stress sensors; the force vibration sensing unit is used for sensing an intrusion behavior, converting the intrusion behavior into an optical signal and inputting the optical signal into the monitoring host; the monitoring host is used for demodulating optical signals and monitoring intrusion behaviors. According to the invention, the accuracy of perimeter security and protection monitoring can be effectively improved, the false alarm rate of perimeter intrusion alarm positioning is reduced, manpower resources are saved, and the cost is low.

The invention relates to the technical field of fiber bragg gratings, and particularly provides a birefringent FBG-based fiber environment event identification method, which comprises the following steps: constructing a spectral pulse matrix according to fast axis spectrums and slow axis spectrums of a plurality of spectral pulses, the spectral pulses being echo spectral pulses transmitted by a birefringent FBG; solving a joint optimization problem, and separating a first matrix and a second matrix from the spectral pulse matrix; solving a first optimization problem of the first matrix based on a first dictionary learning algorithm to obtain a vibration event recognition matrix used for representing a vibration event signal; and solving a second optimization problem based on a second dictionary learning algorithm to obtain a temperature offset feature vector used for representing the temperature change signal, the second optimization problem being determined according to the merged vector of the second matrix. The problem of difficulty in signal decoupling of the FBG in a complex environment in which temperature change and vibration events exist at the same time in the prior art is solved.

The invention discloses a grating tilt angle sensor capable of realizing tilt correction in an installation process based on a strain sensitive principle of a fiber bragg grating, and belongs to the technical field of fiber sensing, the grating tilt angle sensor comprises a grating tilt angle sensor body and an installation component used for being connected with a detected body, and the installation component is connected with the sensor body through a universal shaft. A component for fixing the corrected sensor body is also arranged between the grating tilt angle sensor body and the mounting component, or a component for fixing the corrected sensor body is also arranged between the grating tilt angle sensor body and the detected body. According to the invention, the initial inclination angle generated in the installation process can be compensated, and the inclination angle of the inclination angle sensor after installation is ensured to be 0 degree, so that the inclination angle measurement of the device is more accurate, and the installation is more convenient.

The invention discloses a bolt washer sensor based on a fiber Bragg grating, which is characterized by comprising a double-layer composite washer, the double-layer composite washer comprises an inner ring and an outer ring, the inner ring is made of an FR4 epoxy resin material, and the outer ring is made of an aluminum alloy material; the strain body structures are symmetrically arranged on the two sides of the outer ring and comprise a positive strain body and a negative strain body, and the positive strain body and the negative strain body are both made of aluminum alloy materials; two fiber bragg gratings (FBG) with different central wavelengths are inscribed on the optical fiber, the two FBGs are respectively a first FBG (FBG1) and a second FBG (FBG2), the FBG1 is fixed at the central position of the positive strain body, and the FBG2 is fixed at the central position of the negative strain body. The gasket type sensor is compact in overall structure and resistant to corrosion, and has high repeatability, rapid dynamic response and long-term stability.

An optical sensor includes a probe fiber Bragg grating (FBG) coupleable to a light source, the probe fiber Bragg grating defining a probe spectrum and arranged to provide a probe light signal corresponding to the probe spectrum. A sensing fiber Bragg grating (FBG) defines a sensing spectrum. A spectral shift in the sensing spectrum is responsive to a change in at least one external parameter acting on the sensing fiber Bragg grating. The optical coupler couples the probe optical signal with the sensing fiber Bragg grating to output a spectrally overlapped optical signal. An intensity level of the spectrally overlapping light signal corresponds to an overlap between the detection spectrum and the sensing spectrum. And an optical power regulator coupled to the optical coupler, the optical power regulator arranged to adjust a baseline of the intensity level to change a sensitivity of the optical sensor.

The invention relates to the technical field of bionic touch, in particular to a flexible touch sensor based on a filling structure and a preparation method. The flexible touch sensor comprises a flexible layer, and the flexible layer is provided with a containing groove. The liquid filling material is arranged in the accommodating groove; the sensing group is arranged on the side wall of the accommodating groove, the sensing group comprises a first fiber bragg grating and a second fiber bragg grating, and the first fiber bragg grating and the second fiber bragg grating are symmetrically arranged on the two side walls of the accommodating groove; and the packaging film is used for packaging the liquid filler and the sensing group. According to the embodiment of the invention, the miniature accommodating groove and the liquid filler are arranged on the flexible layer, so that the flexibility and the fitting property of the sensor can be improved, the fiber bragg gratings are symmetrically arranged on the accommodating groove, the lateral pressure has two opposite strains, and the temperature influence is eliminated through differential processing; and constant cooling and thermal diffusion stabilization effects on the sensing cavity in a dynamic environment can be realized.