120 results about "Fiber sensor" patented technology

The invention discloses an automatic feeding device of a plunger piston core of an automobile fuel injection pump. The device comprises a base, a circular disc type electromagnetic vibration hopper, a linear electromagnetic vibration hopper, a plunger piston core direction adjusting mechanical arm, and a sensing and detection device, wherein the circular disc type electromagnetic vibration hopper, the linear electromagnetic vibration hopper and the plunger piston core direction adjusting mechanical arm are arranged on the base; the sensing and detection device is arranged on the linear electromagnetic vibration hopper. The circular disc type electromagnetic vibration hopper comprises a circular electromagnetic vibration hopper base and a spiral material disc connected with the vibration base; the linear electromagnetic vibration hopper comprises a linear vibration base, a linear material groove connected onto the base, and a workpiece movement pneumatic assisting device mounted on the material groove; an outlet end of the spiral material disc is in butt joint with an inlet end of the linear material groove. The direction adjusting mechanical arm is adsorbed on the base by a strong magnetic gauge stand; the sensing and detection device comprises a plunger piston core direction judging optical fiber sensor, and a workpiece in-place and displacement laser sensor. According to the automatic feeding device, the automatic oriented arrangement and transmission of the automobile fuel injection pump can be realized.

The invention relates to a novel fiber sensor which is used for measuring the size and the direction of a tilting angle and is manufactured by utilizing strain effect of a fiber grating and wavelength measuring technology based on the prior fiber Bragg grating. The system consists of a pedestal (1), a supporting column (2), a top disc (3), fiber gratings (4), a weight (5) and fibers (6). When the sensor tilts for a certain angle, the sensor causes three fiber gratings to have different stresses and utilizes the drifting amount of central reflective wavelength of the fiber grating measured by the wavelength measuring technology to reversely calculate the size and the direction of the tilting angle. A common fiber grating is sensitive to a temperature; and as the novel fiber sensor uses the three fiber gratings positioned in the same environment and the consistent drifting amount of the central wavelength caused by the temperature can be compensated in the angle analyzing and calculating process, the novel fiber sensor is insensitive to the temperature when measuring the tilting angle. The novel fiber sensor has a simple principle, has the characteristics of light mass, anticorrosion, electromagnetic interference resistance, safe and reliable use and the like, also has the unique advantages of small size, high sensitivity, easy coupling with fiber, small consumption, integration of sensing and transmission and easy wavelength division multiplex and the like and is convenient to realize; therefore, the novel fiber sensor can be used as a tilting angle sensor of various fields.

The invention belongs to the technical field of wearable sensing, in particular to an electrochemical sensing fabric and a preparation method thereof. The electrochemical sensing fabric disclosed by the invention is woven by a fiber sensor, and has a silver/silver chloride fiber reference electrode woven therein; the fiber sensor comprises a glucose fiber sensor, a sodium ion fiber sensor, a potassium ion fiber sensor, and a pH fiber sensor. The electrochemical sensing fabric can monitor glucose, sodium ions, potassium ions, calcium ions and a pH value in sweat. The electrochemical sensing fabric is woven in a garment and connected with a wireless sensor to construct a smart sensing garment, which can transmit monitored sweat component information to a mobile terminal such as a smart phonein real time; and the electrochemical sensing fabric is an ideal platform for realizing real-time wearable monitoring and has a broad application prospect in the field of wearable electronics.

The invention provides a static pressure balanced fiber ultrasonic sensor array measuring system which comprises an extrinsic Fabry-Perot fiber ultrasonic sensor, a light source module, a wavelength division multiplexer, a tunable narrow-band optical filter, and a photoelectric detection and signal processing unit. The light source module is connected with a first port of the wavelength division multiplexer; a third port of the wavelength division multiplexer is connected with the fiber sensor by a transmission fiber; other output ports of the wavelength division multiplexer are respectively connected with different fiber sensors; therefore, light beams with different wavelength ranges respectively act on the different fiber sensors, simultaneously, a plurality of different interfered light beams reach a first port of the tunable narrow-band optical filter by a second port of the wavelength division multiplexer; and a second port of the tunable narrow-band optical filter outputs a narrow-band light to a photoelectric detection tube which converts optical signals into electric current signals and sends the electric signals into the signal processing unit. The static pressure balanced fiber ultrasonic sensor array has the beneficial effects of being capable of automatically eliminating the deviation of the working point of the sensor caused by static state pressure variation and temperature change and increasing the wavelength division multiplexing capability of the measuring system.

The invention discloses an earth pressure balance type shield simulation test system. A model shield machine is arranged in a rectangular earth mass chamber, wherein the upper part of the rectangular earth mass is opened; a simulation earth mass is filled in the rectangular earth mass chamber; an axle wire of the model shield mechanism is overlapped with that of an earth mass chamber; the simulation earth mass is covered with one concrete cushion; an upper surface of the concrete cushion is connected with a horizontal loading beam through more than two earth pressure jacks; the horizontal loading beam is connected with the bottom of the earth mass chamber through an anchor cable; and an earth mass pressure box, a fiber grating sensor and a displacement meter are embedded in the simulation earth mass and electrically connected with a data acquiring and processing device respectively. The earth pressure balance type shield simulation test system can simulate the influence of shield tunnel construction among urban subway areas on stratum and a surrounding environment more conveniently, more truly and effectively and provides more true and accurate experimental data for the construction and the design of the tunnel so as to ensure the high efficiency and the safety of the construction of urban shield tunnels.

The invention discloses a symmetrical all-fiber Fabry-Perot sensor, a first single-mode fiber is welded with a first multi-mode fiber, and a second single-mode fiber is welded with a second multi-mode fiber; tail ends of the first multi-mode fiber and the second multi-mode fiber are provided with concave cavities; the concave cavities of the first multi-mode fiber and the second multi-mode fiber are in butt joint with each other to form an FP cavity. According to the symmetrical all-fiber Fabry-Perot sensor and the manufacturing method thereof provided by the invention, the structure is small and exquisite, manufacture is easy and cost is low, the fiber sensor can utilize a chemical corrosion method to obtain a long Fabry-Perot cavity, is symmetrical in structure and low in stripe fineness, is little affected by temperature, and can utilize a phase method based on Fourier transform to realize measurement of pressure and strain under high temperature.

Disclosed are a device, system, and method for identifying an area of ablated tissue and/or assessing contact between a treatment element and tissue and/or assessing occlusion of a body lumen by the treatment element. Specifically, the device, system, and method may include a device having one or more fiber sensors and a processing unit for receiving emitted and/or reflected light from tissue andmaking one or more determinations based on the received light regarding ablated tissue, tissue contact, and/or occlusion. Each of the fiber sensors may include at least one multi mode waveguide segment and at least one single mode waveguide segment, or each of the fiber sensors may be single mode waveguide including fiber Bragg grating for assessing strain of a treatment element by tissue contact.The processing unit may include a beam processing apparatus and a hyperspectral imaging and analysis apparatus, and may optionally include a light source.

A fiber optic sensor and related method are described, with the sensor including a cross-coupling element in the optical path between a polarizing element and a sensing element, but separated from the sensing element itself; with the cross-coupling element generating a defined cross-coupling between the two orthogonal polarization states of the fundamental mode of a polarization maintaining fiber guiding light from the light source to the sensing element thus introducing a wavelength-dependent or temperature-dependent sensor signal shift to balance wavelength-dependent or temperature-dependent signal shifts due to other elements of the sensor, particularly signal shifts due to the wavelength dependence of the Faraday effect or the electro-optic effect constant.

The invention discloses a pipeline monitoring device and system based on distributed fiber sensors and acoustic wave. The device comprises a pipeline (21); distributed fiber sensors (22) are laid in a monitoring area of the pipeline (21); acoustic sensor units (23) are installed at two ends of the pipeline (21) or on the pipeline (21) section by section; the device further comprises an optical power detection module (24 and 25) and an acoustical signal receiving and processing device (26); the monitoring area of the pipeline refers to at least one of the outside of the pipeline, the outer wall surface of the pipeline, the inside of the outer wall of the pipeline and the inside of the pipeline. The pipeline monitoring device and system based on the distributed fiber sensors and acoustic wave has the advantages that the distributed fiber sensing technique and the acoustic sensing technique are combined, detection results of the distributed fiber sensors and those of the acoustic sensor units are comprehensively considered, the distributed fiber sensing technique and the acoustic sensing technique are mutually complementary, high-reliability detection is achieved, false alarm rate is reduced, and positioning precision is improved.

The invention relates to a sensing head of a fluorescent fiber sensor. The sensing head of the fluorescent fiber sensor is of a wheel-shaped microstructure and comprises a fiber core, a coating layer and an air hole, wherein the fiber core and the coating layer are connected through tiepieces; and the inner wall of the air hole is coated with one layer of nanogold/methyl methacrylate with the thickness of 20 nm. A preparation method of the sensing head of the fluorescent fiber sensor comprises the following steps: preparing the nanogold/methyl methacrylate; coating the nanogold/methyl methacrylate on the inner wall of the air hole of the wheel-shaped microstructure fiber; and after coating is finished, roasting for 6 hours by controlling the temperature to be 50 DEG C so as to volatilize a dichloromethane solvent to obtain the sensing head of the fluorescent fiber sensor. Compared with the like products, the sensing head of the fluorescent fiber sensor has the advantages that the lower limit and the sensitivity of fluorescent detection of the sensing head can be increased by 20 times; the required sample amount is at nL amount order.

The invention discloses a seepage continuous monitoring experiment apparatus and method under a special stratum environment condition. At an early stage, stratum feature parameters are obtained through engineering onsite investigation, stratum sample preparation is carried out in the experiment apparatus, by use of the experiment apparatus, an embankment model of an embankment project area is erected, then through adjustment of such parameters as a water level elevation, a water temperature, a temperature and the like, by use of a distributed fiber sensor, a continuous seepage monitoring process is realized, after an experiment ends, relations between the parameters and set seepage thresholds are obtained, a data basis can be provided for seepage monitoring of different embankment projects, and effective monitoring and timely early warning of the different embankment projects is realized.

A fluid diffusion resistant tube-encased fiber grating pressure sensor includes an optical fiber 10 having a Bragg grating 12 impressed therein which is encased within a sensing element, such as a glass capillary shell 20. A fluid blocking coating 30 is disposed on the outside surface of the capillary shell to prevent the diffusion of fluids, such as water molecules from diffusing into the shell. The fluid diffusion resistant fiber optic sensor reduces errors caused by the diffusion of water into the shell when the sensor is exposed to harsh conditions.

The invention relates to a device for testing railway wagon overloading and unbalance loading by a foundationless-tunnel fiber and a method, relating to the technical field of fiber sensor and overcoming the problems that the existing overloading and unbalance loading detecting technology has low precision and bad anti-electromagnetic interference capability. The device comprises a laser, a coupler, a transmission fiber, fiber Bragg grading strain transducers, a light splitter, a wavelength demodulation device, a data acquisition unit and an analytical processing device; every two fiber Bragggrading strain transducers are symmetrically welded at the bottom parts of upper tracks of a left track and a right track to form a sensor assembly; a first sensor assembly serves as a starting deviceand is arranged at the open end of a detecting area; the coupler is arranged in the middle of the transmission fiber and is connected with the light splitter; ten output channels of the light splitter are respectively connected with ten input ends of the wavelength demodulation device; and the data acquisition unit is connected with the wavelength demodulation device and the analytical processingdevice. The invention is applicable to railway wagon overloading and unbalance loading on-line detection.

The invention relates to the technology of forest protection systems, especially to a method for dynamically monitoring deforestation on a real-time basis and a system therefor, and the method is employed for dynamically real-time monitoring, positioning and alarming deforestation events in protection of a large area forest with a long boundary, and mainly for preventing outsiders from invading and deforesting and destroying the vegetation. Fiber sensors are bound on fences of a forest protection zone, laid on vegetation, or shallowly buried under the ground. The sensors can sense peripheral deforestation events (including sawing off, vibration and pulling), and the fiber sensors and signal acquisition modules, signal transmitting terminals and terminal processors are jointly form a fiber sensor system. Deforestation alarm and position are realized through mach-zehnder interference principle, and deforestation identification is realized through algorithm processing. The cost is low, and the work efficiency is high. Excessive deforestation phenomena can be monitored, and alarm and timely positioning can be done to prevent outsiders from invading in a forest and deforesting.

The invention relates to the technical field of fiber sensor measurement, in particular to a chirped fiber grating sensor and a signal processing method for continuously measuring the speed of impact waves or detonation waves in order to solve the problems of a microwave interference method for measuring the impact waves or detonation waves by the aid of the characteristics that the detonation waves or impact waves act on a chirped fiber grating, the length of the fiber grating is decreased, and accordingly the light amplitude of return signals is decreased. The signal processing method includes the steps: acquiring the speed of continuous impact waves or detonation waves in a measuring environment by a signal acquisition light path; converting the speed into continuous light signals to be outputted and converting the light signals into electric signals by a photoelectric converter; processing data of voltage signals outputted by the photoelectric converter by a processor; and calculating the speed of the acquired continuous impact waves or detonation waves in the measuring environment. The chirped fiber grating sensor and the signal processing method are applied to the technical field of fiber sensor measurement.

The invention discloses a pipeline monitoring method based on distributed fiber sensors and acoustic wave. The method includes the steps of laying distributed fiber sensors in a pipeline monitoring area, installing acoustic sensor units at two ends of a pipeline or on the pipeline section by section, and monitoring the pipeline in real time with both the distributed fiber sensors and the acoustic sensor units; providing optical power detection modules for the distributed fiber sensors, and providing an acoustical signal receiving and processing device for the acoustic sensor units; in case of leakage of the pipeline, judging the condition by making comprehensive use of leakage signals detected by the distributed fiber sensors and leakage signals detected by the acoustic sensor units. The pipeline monitoring method based on the distributed fiber sensors and acoustic wave has the advantages that the distributed fiber sensing technique and the acoustic detection technique are combined and are mutually complementary, false alarm rate is reduced, and positioning precision is improved.

The invention discloses an earthquake underground fluid inspection well and a system and a method used the earthquake underground fluid inspection well to detect seismic precursor abnormal information of gap pressure diffusion coefficients, which relate to earth physics and quakeproof disaster reduction technology. The earthquake underground fluid inspection well is arranged vertical to the direction of strata, a corrosion resisting seal stainless steel sleeve is installed in the center of the inspection well in the middle, cement is used at the bottom and the top of the inspection well for fixing a sleeve, a stainless steel clamp is adopted to fix the sleeve at the position of the axial center of the stainless steel sleeve additionally, multimode fibers are buried in a gap between the sleeve and the well wall, ore particles are filled in the gap between the sleeve and the well wall, so that an even gap medium layer is formed. A special high-resolution-ratio fiber sensor collects gas pressure dynamic response signals stimulated by earthquake cutting waves, a data analyzing system is integrated through a maximum likelihood deconvolution space-time conservation method and a weight integral method chips, characteristic scale of the dynamic gap pressure diffusion coefficients related to the cutting waves is obtained through calculation, an earthquake source generated the earthquake cutting waves is carried out high-precision earthquake location, scientific decision-making data with earthquake source physical significances are provided to seismic prediction. The obtaining method of the characteristic scale of the dynamic gap pressure diffusion coefficients can be used for well wall fracture monitor of oil exploitation wells and carbon dioxide geology seal injection wells.

A system for interrogating sensors in a fiber optical sensor network includes groups of sensors. The sensors in one group operate at different wavelengths, and the sensors of other groups may have overlapping wavelengths. A light source generates a broadband light signal, input and output means for guides the broadband light to the fiber optical sensor network for illuminating the sensors and for coupling the light signal coming from the sensors of the fiber optical sensor network to the detection system, and a detection system detects the received light signal, during a detection integration time. The system is arranged for selecting pre-dominantly the received light coming from the different sensors of a selected group of sensors using a code-division multiplexing technique and simultaneously detecting sensors of the selected group of sensors wavelength-division multiplexing technique.

The invention discloses a photoelectric composite inclinometer and an inclinometer system. The photoelectric composite inclinometer comprises a PVC pipe, a flexible board, a plug and a sealing cover,wherein the flexible board is inserted into the PVC pipe, the plug is arranged at one end of the PVC pipe, and the sealing cover is arranged at the other end of the PVC pipe. On the flexible board, aplurality of fiber Bragg grating sensors and resistance sensors are alternately arranged at equal intervals in the length direction. The photoelectric composite inclinometer disclosed by the inventionhas the beneficial effects that deformation sensitivity is high and measurement accuracy is high; and no charge is carried, size is small, weight is light, waterproof performance is good, and servicelife is long. The inclinometer system comprises an optical divider, an interrogator, a local monitor, an upper server, a remote terminal, a remote alarm and a plurality of photoelectric composite inclinometers. The inclinometer system disclosed by the invention has the beneficial effects that data acquired by all the fiber Bragg grating sensors or data acquired by all the resistance sensors can be selected and processed, or the data acquired by the fiber Bragg grating sensors and the data acquired by the resistance sensors are processed at the same time, thereby being flexible to use and highin reliability.

The invention discloses a lithium ion battery monitoring multifunctional fiber sensor, a system with the sensor and a manufacturing method of the sensor. The multifunctional fiber sensor comprises a charged state sensor and a temperature sensor in serial connection, each of the charged state sensor and the temperature sensor uses a multi-mode fiber as a substrate, and each multi-mode fiber includes a silica core, a fluorine-doped cladding and a acrylic ester coating from inside to outside; the multi-mode fiber is etched in hydrofluoric acid in a wet method, so that the fluorine-doped claddingis thinned to form a fiber evanescent wave sensor, namely the charged state sensor; and the temperature sensor is connected in series to the back end of the charged state sensor, and the fluorine-doped cladding of the multi-mode fiber of the temperature sensor is etched and thinned and coated with a fluorescent layer with PMMA as the matrix. Two important parameters, namely temperature and chargedstate, of the lithium ion battery can be measured at the same time without mutual interference, and the sensitivity is high.

The invention discloses a concrete crack self-healing detection method. According to the invention, detection is carried out under a crack opening state, minimum depth, maximum depth and width of a detection position are obtained in a crack detection reception instrument; the crack position on the surface of a member is observed by eyes, a crack distribution map is drafted, and the forms, strip numbers, positions, lengths and directions of the cracks are recorded; a fiber grating sensor is placed in a crack structure, a loop metal conduit is fixed outside the fiber sensor, then the loop metal conduit and the fiber sensor are embedded into a concrete structure, the metal conduit is taken out or the fiber sensor is coated with a metal conduit having consistent expansion coefficient with the concrete, and the external load is transmitted to the fiber sensor through the metal conduit for measuring the corresponding data. The fiber lead performs dynamic conduction through a corresponding inductor by the method, the operation process of a whole apparatus is simple, the usage is convenient, and the dynamic accuracy of the detected data is high.

The invention relates to a device for safely laying fiber grating sensors and a construction method, and belongs to the technical field of fiber sensor application. The device comprises a thin-wall protective sleeve and a reserved hole channel, wherein the thin-wall protective sleeve is arranged at a to-be-monitored part of a concrete structure; a grouting hole and an exhaust hole are formed in the thin-wall protective sleeve; the inner wall of the thin-wall protective sleeve is uniformly coated with a release agent; the fiber grating sensors penetrate into the thin-wall protective sleeve, andthe two ends of the fiber grating sensors are temporarily fixed; and the grouting hole is used for pouring cement mortar. According to the construction method, the construction process of firstly penetrating bundles, then grouting and then pouring concrete is adopted, the extensive operation environment of the concrete structure engineering is overcome, safe laying construction of the fiber grating sensors for concrete is realized, and the possibility of damage and breakage of the fiber grating sensors is greatly reduced. Moreover, the fiber grating sensors are directly wrapped with the cement mortar, physical quantities such as real temperature and strain of the concrete structure can be directly monitored, the sensitivity is high, the monitoring precision is high, the efficiency is high, and technical support is provided for structural damage monitoring and evaluation.