32results about How to "Achieving temperature self-compensation" patented technology

The invention discloses a distributed optical fiber large-deformation measuring sensor which is characterized in that a stain sensing optical fiber is embedded into a large-deformation measured spring, particularly embedded into or fixed on a spring rod interlocked with the spring; one end of the large-deformation measuring sensor is fixed with the spring rod so that when the spring expands to become deformed, the deformation quantity of the spring is corresponding to that of the spring rod and has the corresponding relation with the deformation quantity of the stain sensing optical fiber; the deformation quantity of the spring can be obtained by measuring strain of the optical fiber, thus realizing the conversion from the large-deformation of the spring to the little strain of the optical fiber; and the stain sensing optical fiber is connected with the optical fiber of a Brillouin back scattering luminous power measuring instrument. The sensor is characterized by large measuring range, variable measuring range, stably, reliability, corrosion resisting, temperature self-compensation, realization of a plurality of series connections, easy to industrial production, convenient installation, etc.

The invention discloses a contact type optical fiber grating ice-pressure sensor with better stability, which belongs to the field of sensing technologies. The sensor is characterized in that the contact type optical fiber grating ice-pressure sensor consists of a metal bottom plate, a metal protective case, a metal force-bearing panel, a clamping piece, a uniform strength beam, a micro-optical fiber grating strain sensor and a transmission optical cable component. The sensor is mounted on the structure through the metal bottom plate, the clamping piece fixes the micro-optical fiber grating strain sensor on the uniform strength beam through a screw, and the different shapes of the metal force-bearing panel can be changed according to the different force application structures; in addition, the measurement sensitivity of the sensor can be adjusted by changing the dimensions of devices according to actual demands, thereby being applicable to different types of model tests. The ice-pressure sensor can indirectly measure the ice-pressure by measuring the strain, and the pressure sensitivity coefficient of the sensor is improved by utilizing the natures of an optical fiber grating, which is not affected by materials. The ice-pressure sensor can well eliminate the affects of eccentric force on the measured value and realize the temperature self-compensation; and the ice-pressure sensor can simultaneously overcome the shortcomings that the traditional electric sensor is vulnerable to electromagnetic interferences, the long-term stability is poor and the like, and has the advantages of high precision, small volume, light weight, small affects on the natures of the structure and the like.

The invention relates to a tilt angle sensor based on optical fiber Bragg gratings and a method for measuring a tilt angle of the tilt angle sensor and belongs to the technical field of measurement of a structural tilt angle. The tilt angle sensor comprises a fixed base plate (12), a fixed pressing block (6), a thin-wall type uniform-section metal beam (9) and a quality block (7), wherein the upper end of the thin-wall type uniform-section metal beam (9) is arranged on the fixed base plate (12) in a mode of fitting with the fixed pressing block through a first movable pressing block (10) and a fifth screw (11); the quality block (7) is fixed at the lower end of the thin-wall type uniform-section metal beam (9) through a sixth screw (15) and a second movable pressing block (16); and a first optical fiber Bragg grating (13) and a second optical fiber Bragg grating (14) are respectively adhered to opposite positions on two sides of the thin-wall type uniform-section metal beam (9). By the method, the size and direction of the tilt angle can be detected according to a correspondence relation between the change of central wavelengths of the two optical fiber Bragg gratings and the tiltangle. The invention is high in measurement accuracy and has a temperature self-compensation function.

The invention provides a fiber bragg grating strain sensor. The sensor comprises a substrate, two compensation arms and fiber bragg gratings, wherein the two compensation arms are symmetrically arranged on two sides of the substrate; one side of an upper end of each compensation arm, which is close to a substrate center, is provided with an optical fiber fixing point; one side of a lower end of the each compensation arm, which is far away from the optical fiber fixing point, is fixed to the substrate; and the fiber bragg gratings are arranged on the two compensation arms through the optical fiber fixing points. In the invention, an expansion direction of the compensation arms is opposite to an expansion direction of the substrate so that expansion quantities and the expansion directions of the substrate and the compensation arms are different, expansion quantities of the fiber bragg gratings are compensated and a temperature cross interference is eliminated.

The invention discloses a temperature self-compensating fiber grating micro force sensor and a manufacturing method thereof. The sensor comprises a force-bearing end cover, a sensor upper shell, a sensor lower shell, a hard core, a supporting cylinder and a round elastic diaphragm, wherein the hard core comprises a hard core screw and a hard core nut; the top part of the supporting cylinder passes through the sensor upper shell, and the bottom part is fixed with the hard core screw; the supporting cylinder is internally provided with a fiber, a first fiber grating and a second fiber grating are carved on the fiber, one end of the first fiber grating is fixedly connected with the top part of the upper shell and the other end is fixed with the hard core screw and is in a tensioning state, and one end of the second fiber grating is connected with the lower part of the hard core screw and the other end passes through the sensor lower shell and is in a free elastic state. The structure is simple; the force measurement sensitivity and the force measurement range of the sensor can be changed in a large range, production and manufacturing of batch sensors with multiple specifications are facilitated; temperature self compensating can be realized; and long-term and reliable effective monitoring by the sensor in a temperature-varying environment can be realized.

A temperature-self-compensating fiber-integrated bragg grating strain transducer comprises a fiber bragg grating transducer body composed of two bare fiber bragg gratings with the same model but different wave bands, an elastic sheet composed of high-elasticity metal thin sheets, clamping pieces, bases, a Z-shaped movable piece composed of L-shaped steel plates and a metal frame. The metal frame is provided with a frame shaft hole and a frame connecting shaft, and a connecting shaft of the Z-shaped movable piece penetrates through the frame shaft hole to be fixedly connected with the base II through the clamping piece II and can relatively move in the frame shaft hole. One end of the elastic sheet is fixedly connected with the L-shaped plates of the Z-shaped movable piece, and the other end of the elastic sheet is fixed on the metal frame. The frame connecting shaft is fixedly connected with the base I through the clamping piece I. A cantilever beam stress structure is formed by the frame, the Z-shaped movable piece, the elastic sheet, the bases and the clamping pieces. Under the working state, the two bases are fixed on the surface of a component to be tested in a bolting or welding mode, and when the component to be tested is strained, the bases and the Z-shaped movable piece are driven to drive the elastic sheet to deform, and then the fiber bragg gratings deform.

The invention discloses a load sensor element used in a humid water environment, comprising a substrate, a transition buffer layer arranged on the upper surface of the substrate, an insulating layer arranged on the upper surface of the transition buffer layer, and a transition buffer layer arranged on the upper surface of the insulating layer. The functional layer and the protective layer on the upper surface of the functional layer; the base is made of 316L stainless steel, the transition buffer layer is CrNi film, and the insulating layer is TiO 2 film, the functional layer is FeCrMn alloy film, and the protective layer is Al 2 O 3 membrane. In the present invention, in the humid water environment, the load sensor element can be firmly fixed on the sample, and the connection between them is inorganic, thus eliminating zero point drift and creep, realizing temperature self-compensation, and improving the load sensor element. characteristics of the sensitivity and accuracy of the measurement results.

The invention discloses a temperature self-compensation high-resolution high-frequency demodulation system and method for a fiber bragg grating. According the optical path transmission process, a tunable narrow-band laser device emits narrow-band light which is divided into two light beams through an optical fiber splitter, the two light beams are output through two output ports of the optical fiber splitter respectively, one light beam is transmitted to a sensing grating through the input end of a first optical fiber coupler and returns to the other input end of the first optical fiber coupler after passing through the sensing grating to be transmitted to a first photoelectric detector and be converted into a voltage signal, and then the voltage signal is transmitted to a data colleting and processing device; the other light beam is transmitted to a temperature compensation grating through a second optical fiber coupler and returns to the other input end of the second optical fiber coupler after passing through the temperature compensation grating to be transmitted to a second photoelectric detector and be converted into a voltage signal, and then temperature compensation is performed on the voltage signal through a temperature self-compensation device, so that the variable quantity of the output center wavelength of the tunable narrow-band laser device is obtained. The temperature self-compensation high-resolution high-frequency demodulation system and method have the advantages that temperature self-compensation is achieved, and the resolution is high.

The invention discloses an FBG (Fiber Bragg Grating) liquid level sensor and a preparation method thereof. The sensor comprises a metal base, pressure sensing membranes, two metal capillary tubes, optical fibers carved with two FBGs having different wavelengths, pins and a tail fiber sleeve, wherein the optical fibers penetrate into the two metal capillary tubes; an FBG is located in the first metal capillary tube; a sensing FBG is located between the two metal capillary tubes to form a structural unit; the pressure sensing membranes are fixed on the metal base, and an air cavity is formed between the pressure sensing membranes; the structural unit is located in the air cavity; the first metal capillary tube is located at the center of each pressure sensing membrane; the optical fibers are vertical to the plane where the pressure sensing membranes locate; the second tube capillary tube stretches out of the metal base and is positioned by the pins; and the tail fiber sleeve is fixed at the lower end of the metal base to be communicated with atmosphere. The metal capillary tubes are titanium tubes; and the metal base is made of stainless steel. The sensor can be applied to inflammable, explosive and strongly-corrosive liquid, and has the advantages of wide dynamic range, an FS with the precision of 0.5%, a linearity of 99.7%, electromagnetic interference resistance, easy reusability and the like.

The application discloses a novel fiber grating six-dimensional force sensor and its main structure and measurement method. The main structure provided by the application has good symmetry and is easy to process and manufacture. The fiber grating six-dimensional force sensor provided by this application has only 12 fiber grating elements, and compared with the 24 strain gauges generally required by the sensor of the resistance strain gauge group bridge measurement principle, the number of sensitive elements is doubled. . At the same time, the optical wavelength information is used as the output signal of the sensor, which has the advantages of anti-electromagnetic interference and zero drift. The measurement method provided by this application uses the wavelength difference output information of six groups of fiber gratings composed of 12 fiber gratings to realize automatic decoupling output of six-dimensional force and torque measurement information, and realize temperature self-compensation. Therefore, the present invention reduces inter-dimensional coupling and realizes self-decoupling measurement of three-dimensional force and three-dimensional moment.