10results about How to "With anti-electromagnetic interference" patented technology

The invention discloses a distributed optical fiber-grating-based rockburst test system and method, solves the problem that in the prior art, only strain parameters are simply obtained in a rockburst test, and has the beneficial effects of accurately simulating rockburst and obtaining related parameters of the rockburst. According to the specific scheme, the rockburst test system based on the distributed optical fiber-grating comprises a test device, the test device comprises a vibration table, and the vibration table supports a supporting box body; the rock sample is provided with an optical fiber channel, and the distributed optical fiber penetrates into the optical fiber channel; the vibration table, the stress applying component and the drilling disturbance component are respectively connected with the control unit; the monitoring unit is connected with the distributed optical fiber and the grating optical fiber; the monitoring unit sends monitored data to the control unit, and the control unit judges when rockburst is triggered and obtains stress change, elastic strain energy release amount and strain abrupt change time difference at the moment of rockburst when the rockburst occurs.

This invention discloses a fiber Bragg grating level sensor based on liquid pressure conversion, comprising a fiber Bragg grating demodulator, a 2×1 fiber coupler, a transmission fiber, and a sensing unit. The sensing unit consists of a strain-sensing fiber Bragg grating, a temperature-compensated fiber Bragg grating, a sealed cylinder, a support beam, a pressure block, a pressure tension frame, a sealing membrane, and a stop. The pressure block and the pressure tension frame convert liquid level changes into longitudinal displacement changes, causing axial strain in the strain-sensing fiber Bragg grating. This results in a drift in the center wavelength of the strain-sensing fiber Bragg grating, and the liquid level height of the container is measured by monitoring this wavelength change. This invention eliminates the influence of temperature on the liquid level measurement results through a temperature-compensated fiber Bragg grating, offering advantages such as a large measurement range, good practicality, simple structure, low cost, good stability, high sensitivity, and safety and reliability, meeting the needs of measuring liquid levels in large storage tanks and other applications.

The utility model discloses a crack sensing sensor based on optical fiber sensing, and belongs to the technical field of civil structure health monitoring. The problems that the testing precision of an existing crack measuring device is extremely prone to being interfered by the surrounding environment, and the measuring precision is low are solved. The optical fiber grating sensor comprises a mounting shell, a cantilever beam and an optical fiber grating, the mounting shell is of a cavity structure with a fixed connecting end and a stretching movable end, and the fixed connecting end and the stretching movable end can slide relatively; the cantilever beam is of a long-strip-shaped structure with elastic deformation and resilience capacity, the cantilever beam is horizontally arranged in a cavity of the installation shell, the length direction of the cantilever beam is the same as the moving direction of the stretching movable end, the tip end of the cantilever beam is fixedly connected to the fixed connecting end, and the tail end of the cantilever beam abuts against the stretching movable end and is in a bent state. The fiber bragg grating is installed on the cantilever beam, and the length direction of the fiber bragg grating is consistent with the length direction of the cantilever beam. The device is mainly used for measuring cracks in the road surface and the roadbed.

The invention discloses a stress monitoring device suitable for a bearing part of a mixed tower wind driven generator. The stress monitoring device comprises a far-end server, the steel-mixed tower drum is erected on a mixed tower wind driven generator foundation, the fiber bragg grating monitoring device is arranged on the steel-mixed tower drum, the stress monitoring box is arranged on the mixed tower wind driven generator foundation, the fiber bragg grating monitoring device is connected with the stress monitoring box, and the stress monitoring box is connected with the far-end server. The device can accurately monitor the stress of the tower drum.

The invention belongs to the technical field of ship lock structure damage identification, and particularly provides a miter gate crack identification early warning method and system based on a fiber grating displacement sensing technology, and the method comprises the steps: collecting displacement data collected by fiber grating displacement sensors at all measurement points of a miter gate, and carrying out the smoothing of the displacement data through a filter; performing first-order difference calculation and curvature calculation on the smoothed displacement data to obtain a difference curve and a curvature curve; extracting peak points from the difference curve and the curvature curve by adopting a peak point identification method; performing statistical screening on the difference curve peak points of all the measuring points to obtain difference effective peak points, and then screening out curvature effective peak points; performing high-low water level working condition time period interception on the displacement curve, and calculating the displacement difference in the time period; and performing crack early warning according to the change condition of the displacement difference and the historical displacement difference. On the basis of the fiber bragg grating displacement sensing technology, gate crack on-line automatic identification and early warning are achieved.

The utility model discloses a road settlement meter based on an optical fiber technology and belongs to the field of civil engineering measurement. The utility model aims to solve the problem that the traditional settlement meter cannot realize the measurement of single-point differential settlement. The fiber grating settlement meter comprises a settlement meter shell, a supporting cross beam, a fiber grating and a connecting piece, the settlement meter shell is provided with a settlement bottom plate which can move in the vertical direction and deflect in the horizontal direction, the supporting cross beam is of a long-strip-shaped structure with elastic deformation and rebound capacity, and the supporting cross beam is horizontally installed in the settlement meter shell and located on the extending face of the split of the settlement bottom plate; the supporting cross beam is connected with the settlement bottom plate through a connecting piece; the fiber bragg grating is arranged in the middle of the supporting cross beam, and the length direction of the fiber bragg grating is consistent with the length direction of the supporting cross beam. The subgrade settlement measuring device is mainly used for measuring subgrade settlement.

The utility model discloses an optical fiber magnetic field sensor based on an F-P interferometer. The optical fiber magnetic field sensor is composed of a single-mode optical fiber, a capillary glass tube and an annular nickel film. Welding a section of capillary glass tube between two sections of single-mode optical fibers, and plating two layers of superposed annular nickel films on the surface of the capillary glass tube at intervals; when the sensor is placed in an external magnetic field environment, the annular nickel film deforms due to the magnetostriction characteristic of nickel, and the deformation enables the thin inner wall of the capillary glass tube to also deform, so that the cavity length of the interferometer is changed, namely the free spectral range of the F-P interferometer is changed, and finally the reflection spectrum of the sensor drifts; the change of the external magnetic field intensity can be demodulated by recording the drifting of the reflection spectrum of the sensor through the optical fiber spectrometer; the annular nickel films can attract each other due to magnetization of a magnetic field, and the capillary glass tube is easier to deform, so that the change of the cavity length of the interferometer is more obvious, the thin inner wall of the capillary glass tube is easier to deform compared with the thick inner wall of the capillary glass tube, and the sensitivity of the sensor is further improved. The optical fiber magnetic field sensor based on the F-P interferometer has the advantages of being high in sensitivity, resistant to electromagnetic interference, simple to manufacture, compact in structure and the like, and can be used for sensing measurement of magnetic field intensity.

The invention discloses a system and a method for measuring the moisture content of crude oil in real time, and relates to the technical field of oil well exploitation, the technical key points of the scheme are as follows: spectral signal data of each spectral channel in a spectral signal data set is drawn into a spectrogram, and the starting point and the ending point of an absorption band are determined according to a baseline; calculating to obtain the area and the characteristic peak intensity ratio of the absorption band, combining the signal-to-noise ratio of the spectrogram to obtain the spectral signal quality index of each position, and calculating the spectral quality influence coefficient of each position according to the flow velocity change value, the pressure change value and the spectral signal quality change value in the same time interval; the method comprises the following steps: further calculating to obtain a spectrum quality comprehensive evaluation value of each position, comparing the spectrum quality comprehensive evaluation value of each position with a quality threshold value, screening a plurality of monitoring points for measuring the water content of the crude oil according to a comparison result, and calculating the water content of the crude oil through spectrum data of effective measurement points. And the influence of external factors on the measurement result is effectively reduced.

The invention provides a system and method for measuring blood pressure and a puncture needle. The system comprises the puncture needle, an optical fiber sensor, an optical fiber transmission line and a photoelectric conversion regulator. The puncture needle comprises a puncture needle body and a puncture needle core; the body comprises a sheathing canal and a base; the front end of the base is connected with the rear end of the sheath; an infusion interface and a blood pressure measurement interface are arranged at the rear end of the base; the needle core is used for guiding the sheathing canal to puncture into a blood vessel; the sheathing canal is used for introducing blood into an inner cavity of the base; the optical fiber sensor comprises a sensor body, a medical instrument interface and an optical fiber interface; the optical fiber sensor is connected with the blood pressure measuring interface through the medical instrument interface and is indirectly connected with the photoelectric conversion regulator through the optical fiber interface; when the medical instrument interface and the blood pressure measurement interface are in a connected state, the pressure sensitive end of the sensor body enters the inner cavity of the puncture base; the photoelectric conversion regulator is used for emitting laser to the optical fiber sensor and calculating blood pressure information according to optical information reflected by the optical fiber sensor. The electronic sphygmomanometer can measure blood pressure more accurately.

The present invention discloses a belt conveyor state monitoring method and system based on distributed optical fiber temperature-vibration coupling, the monitoring method comprising: obtaining belt conveyor DAS data through a single-mode optical fiber distributed acoustic wave sensor and a DAS demodulator, and obtaining belt conveyor DTS data through a multi-mode optical fiber distributed temperature sensor and a DTS demodulator; obtaining absolute temperature data through DTS data; obtaining low-frequency DAS data through filtering and denoising of DAS data; respectively deriving the absolute temperature function and the low-frequency DAS data with respect to time to obtain a distributed temperature gradient function based on DTS and a distributed temperature gradient function based on DAS; and comprehensively determining belt conveyor faults through DAS data, DTS data, and temperature gradient data for DTS and LF-DAS data. The present invention can combine distributed optical fiber temperature sensing technology and acoustic wave sensing technology, and obtain more accurate and timely belt conveyor fault identification results through the coupling of temperature information and vibration information.