32results about How to "Will not affect measurement results" patented technology

The invention relates to a hydrogen sensor and a Pd film hydrogen sensitive system, wherein the hydrogen sensor comprises introduction fiber, reflection fiber and a hollow tube, a surface of which has a Pd or Pb alloy film, the introduction fiber and the reflection fiber are respectively connected with two ends of a cavity of the hollow tube, two opposite fiber end faces are parallel and constitute an intervene cavity with the tube cavity. According to the Pd film hydrogen sensitive system, light with wide spectrum is transmitted to the introduction fiber of a hydrogen sensor, and intervene light generated on two opposite end of the introduction fiber and the reflection fiber is received, change of the length of the intervene cavity is determined through collecting intervene spectrum signals, further computing concentration of hydrogen. The invention overcomes problems that it is difficult to realize high resolution stable measurement due to light source fluctuation and optical fiber disturbance and the like, and is easy to be affected by temperature in prior art. Measurement result is correct and temperature is strong, cost is low.

The invention discloses a laser interference displacement measuring system. The laser interference displacement measuring system comprises a laser device, a polarizer, an depolarization beam splitting prism, a polarization beam splitting prism, 1/4 wave plates, a pyramid mirror, plane reflectors and a photoelectric detector. Measuring light enters the mobile pyramid mirror, and the light path change of the light reflected back in the original path caused by displacement of the pyramid mirror is four times that of the displacement of the pyramid mirror. In the design of the laser interference displacement measuring system, the measuring light enters and exits the mobile pyramid mirror twice along the same direction by utilizing the polarization optical principle, and an octuple path relation between the displacement of the pyramid mirror and the change of light path difference between the measuring light and reference light is achieved, thereby realizing optical octuple subdivision measurement of the displacement. The laser interference displacement measuring system has the advantages of high measurement resolution and accurate measuring result, is convenient and simple in structural installation, is low in cost, and is wide in application range.

The present invention discloses an F-P and FBG fiber sensor demodulation system, and aims to provide an F-P/FBG demodulation system which is high in wavelength resolution, and enables the demodulation precision to be improved. The F-P/FBG fiber sensor demodulation system of the present invention is realized by the following technical scheme that under the control of an operation control unit, a tunable laser emits out a beam of C-wave band laser of a constant wavelength, by an optical amplifier SOA and/or an optical isolator, and by being divided equally via a beam splitter, the incident light respectively irradiates to n F-P/FBG sensors in one-to-one correspondence, the light reflected by the F-P/FBG sensors is coupled to n phototriodes in one-to-one correspondence by n optical couplers, the optical power is converted into an optical current, the optical current is converted into an optical voltage entering an analog-digital converter by a logarithmic amplifier, the wavelength-reflection optical voltage digital quantity acquired in a time-sharing manner is stored in a memorizer of the operation control unit, the operation control unit carries out the fast Fourier transform on a sampled spectrum, the types of the F-P/FBG sensors are distinguished, and a peak searching demodulation algorithm is carried out to obtain a gradient value containing the cavity length information.

The invention discloses a self-calibration method for the grid point system error of a two-dimensional grid plate. A two-dimensional image measuring instrument with the measurement accuracy not higher than that of the grid plate itself serves as a measuring tool, and the two-dimensional grid plate is installed on an image measuring instrument workbench through a bearing fixture. The coordinates of each grid point on the grid plate are read through the image measuring instrument, then, the grid plate is rotated by 90 degrees relative to the initial position, the coordinates of each grid point on the grid plate are read again, the grid plate is horizontally moved to the left and the right respectively for a grid interval with the initial position as the reference, and the coordinates of each grid point on the grid plate are read again. On the basis of the measurement data of the four grid positions or more positions, a measuring system matrix equation is established, and the grid point system error of the two-dimensional grid plate can be solved based on the least square method. Through the grid point system error self-calibration method of the two-dimensional grid plate, the function of calibrating the two-dimensional grid plate with the low-accuracy image measuring instrument is achieved, no extra high-accuracy calibration tool is needed, and the grid point system error self-calibration method of the two-dimensional grid plate is suitable for calibrating the accuracy of various types of two-dimensional grid plates.

The invention discloses a dual-camera measuring method for accurate calibration of distance between optical identification points. The method, by calibrating the relative position of the two cameras by using a single-shaft motor displacement platform, increases the calibration precision of a binocular stereo vision system and the measuring precision of 3 dimensional coordinates of the optical identification points, and achieves the purpose of accurate calibration of the distance between optical identification points. The method comprises the following steps: using a calibration board to calibration the binocular stereo vision system to obtain the internal parameter matrixes and deformation parameter matrixes of the two cameras and the rotation matrix and the translation vector of the second camera with respect to the first camera; using the single-shaft motor displacement platform to translate a single optical identification point for a known distance, using the known distance to complete the calibration of the binocular stereo vision system; using the calibrated binocular stereo vision system, based on the basic binocular stereo vision theory, to conduct accurate measurement on the distance between two identification points on a reference scale in a direct way.

The invention discloses a method for hysteresis loop measurement based on digital integration. An R-C (resistance-capacitance) active integrator is used for measuring a hysteresis loop of a magnetic material, and an R-C active circuit is subjected to analog-digital conversion, filtering and accumulation to obtain an integral induced voltage Ei in direct proportion to phi. The method includes the steps: after the induction potential ei generated by measurement changes of magnetic-flux in the magnetic material caused by an external magnetic field H of the magnetic material is amplified by an auto-zero amplifier, outputting integral induced voltage Ei within a period of time; using a high-speed A/D conversion module for converting analog signals of Ei into digital signals, performing A/D conversion for N times within a set timer delta t, and accumulating sigma Ei; obtaining a magnetic flux within delta t according to the equation that phi i=Ei X delta t; and subjecting all phi within the measurement period to arithmetic operation to obtain the magnetic flux of the external magnetic H of a corresponding tested sample. Hysteresis loop graphs of magnetic material materials have high reproducibility and closing performance.

The invention discloses provides an online flexible wheel hub internal diameter measuring apparatus based on laser automatic rotation scanning and an application method thereof. The apparatus is characterized in that the apparatus comprises a master control system, a to-be-measured wheel hub, a servo motor, a laser displacement sensor, a precision power transmission device, a rotating shaft positioning device and a wheel hub placing reference surface. On the premise of wide measuring range (the to-be-measured diameter range difference can reach 20 mm), the measuring precision of +/- 5 micrometers can be reached through key technologies including automatic online error correction and automatic online compensation calibration etc., oil stain spots on the surface of the internal diameter of the wheel hub and abnormal values generated by abnormal burrs can be automatically eliminated, and the influence on measuring results can be avoided; besides, the installation is convenient, the maintenance and the usage are convenient, the cost is low, and compared with the conventional contact precision measurement (the to-be-measured diameter range difference is 2 mm), the measuring range is wide, and the apparatus can be applicable flexible measurement of various wheel hubs.

The invention discloses a surface water conductivity non-contact measurement device and method. In the invention, an alternating current signal is output by an alternating current excitation source and is applied to an excitation electrode on the outer bottom side of a floating box through an induction module; a current signal reflecting the surface water conductivity information is obtained by a detection electrode; the current is amplified by a signal processing circuit, and is rectified and filtered to obtain a direct current voltage signal which is easy to measure; and a relational model of the conductivity and the output direct current voltage is established. According to the correspondence of the conductivity and the voltage, a surface water conductivity value can be obtained. In the invention, the influence of coupling capacitance on conductivity measurement is effectively eliminated by using a serial resonance method; and the device and the method can be used for measuring surface water conductivity. The device has the advantages of simple structure, no contact of the electrode and the surface water, high anti-interference capacity, low cost and the like; and an effective method is provided for outdoor long-term on-line detection of the conductivity of the surface water.

The invention discloses an induction type liquid metal electromagnetic flowmeter which comprises a circular flow channel, a heat insulation layer, excitation coils, an excitation power supply, an induction signal pickup coil, a signal processing module and a shielding layer. The two excitation coils are located at the two ends of the electromagnetic flow meter, the winding directions of the coilsare opposite, the number of turns is the same, power is supplied by the excitation power source, the excitation power source can generate high-frequency alternating-current electric signals, and the two excitation coils generate magnetic induction intensity in the flow channel in the opposite directions and the same size. When the liquid metal does not flow, induced magnetic fields generated by the two sets of magnet exciting coils counteract each other. When liquid metal flows, a magnetic field at the position of the induction signal pickup coil can be changed, then alternating induced voltage in direct proportion to the flow of the liquid metal is generated in the induction signal pickup coil, and a flow signal is obtained through the signal processing module. The induction type liquid metal electromagnetic flowmeter is suitable for measuring the flow of liquid metal, such as sodium, lithium, lead-bismuth alloy, sodium-potassium alloy and the like.

The invention provides a method for detecting the interface pressure of a medium-voltage cold-shrinkable cable joint, which includes the following steps: S1, preparing and installing a test platform and sensors: selecting a number of cable core samples with standard cross sections according to the specification of the cable joint, wherein each cable core sample is equipped with a thin film pressure sensor; S2, installing the cable joint: installing the cable joint on the cable core sample with the smallest standard cross section, and allowing the cable joint to retract and become stable; S3, measuring the interface pressure: measuring the interface pressure of the cable joint by the corresponding thin film pressure sensor; S4, after the measurement in S3, pushing the cable joint to the next cable core sample with a standard cross section to test the distribution of the internal interface pressure of the cable joint; and S5, recycling the cable joint: after all tests are completed, connecting the cable core sample with the largest cross section with a support sleeve, and pushing the cable joint to the support sleeve through a hydraulic press to restore the cable joint to an unused state.

The invention relates to the technical field of semiconductor device failure analysis, and especially relates to a method and system for measuring a saturation current of an element. The method comprises the steps: providing a probe bench which comprises an adsorption chuck, an electric monitor, and a plurality of probes; putting one element on the adsorption chuck, and enabling the element to be electrically connected with the electric monitor; enabling the probe bench to apply one fixed voltage to a grid electrode of the element through employing the first probe, and applying variable currents at two ends of a trench of the element through employing the second and third probes; and monitoring the variable currents at two ends of the trench through employing the electric monitor.

The invention provides a working method of a 3D visual scanning detection device. The 3D visual scanning detection device comprises a detection table, a projection light source is arranged below the detection table, a projection screen parallel to a transparent platform is erected right above the detection table, and at least one group of cameras is erected above the projection screen; a multi-axis motion platform is arranged on the detection table, and a probe module is fixed at the moving end of the multi-axis motion platform; the probe module is provided with a structured light module, and the structured light module can emit laser beams in the circumferential direction and project the laser beams to the projection screen; and the probe module comprises a fixed part which is fixed relative to the multi-axis motion platform and a movable part which moves relative to the multi-axis fixed platform, and the movable part is provided with a measuring ball which is in contact with a measured object. The detection device does not depend on a multi-axis motion platform and the precision of the probe, the manufacturing precision requirement of the whole machine can be reduced by increasing the height of the projection screen, the cost is greatly reduced, the trigger signal delay of the probe does not influence the measurement result, and the stability is high.

The invention belongs to the field of optical detection, and particularly relates to a high-precision optical film absorption axis measuring device which comprises a measuring workbench, a light source module, a depolarizer, a standard polarization module, a product carrying table for placing the optical film to be tested, a photoelectric detector and a data processing module electrically connected with the photoelectric detector, and only the optical film to be tested needs to be placed in the product carrying table during use, after the light emitted by the light source module sequentially passes through the depolarizer, the standard polarization module, the optical film to be tested in the product carrying table, the light is incident to the photoelectric detector to result in the photoelectric effect, the data processing module acquires the angle of the absorption axis of the optical film to be tested according to the photoelectric effect of the photoelectric detector, and the light emitted by the light source module is filtered into non-polarized light after passing through the depolarizer, so that the influence on the measurement result is avoided, the measurement precision is high. The device is simple in integral structure, easy to install and use and maintain in the later stage, low in manufacturing and using cost, time and labor saving, high in working efficiency, andwide in application prospect.

The invention discloses an online detecting device for the liquid flow of a gas-liquid mixture. The device comprises a liquid inlet pipe, a second valve, a first valve, a third valve, a second switch,a first switch, a first soft rope, a first floating ball, a second soft rope, a second floating ball, a detection oil box, a fifth valve, an exhausting pipe, a seventh valve, a sixth valve, an auxiliary oil box, a fourth floating ball, a fourth soft rope, a third floating ball, a third soft rope, a third switch, a fourth switch, a fourth valve and a liquid drainage pipe. According to the device,oil feeding and liquid drainage of the detection oil box and the auxiliary oil box are controlled by controlling the open and closed states of the valves, the switches are triggered through the floating balls and the soft ropes, then the liquid levels in the oil boxes are detected, and the open and closed states of the valves are controlled according to the liquid levels. The device has the main advantages that the liquid flow in produced liquid is measured in a mechanical mode through coordination action of the switches and the valves, so that effects of the adhesivity of gas and crude oil inthe produced liquid on the measurement result are avoided, the measurement principle is simple, and the result is accurate.