54results about How to "High accuracy of measurement results" patented technology

The invention provides a binocular photogrammetry method of large flexible structure vibration displacement, and belongs to the technical field of flexible structure dynamic analysis and measurement. The binocular photogrammetry method of large flexible structure vibration displacement aims to solve the problem that the existing contact measurement impacts performance of a flexible structure. Firstly, industrial cameras are demarcated; then, shock excitation is conducted on the flexible structure to be tested, all the industrial cameras are controlled to be triggered synchronously through a single-chip microcomputer, and shooting of vibration displacement is conducted on the point to be tested of the flexible structure to be tested; next, images obtained by shooting of all the industrial cameras are dealt with, pixel coordinates of the point to be tested are obtained through an angular point detection algorithm, object space coordinates of the point to be tested at each point of time are obtained through a binocular three-dimensional reconstruction technology, and thus the vibration displacement curve of the flexible structure to be tested is obtained. The binocular photogrammetry method of large flexible structure vibration displacement is applied to measuring vibration displacement of the flexible structure.

A low coherence light of wide range is fed into a Fabry-Perot load cell having a measured clearance varied in response to physical quantities such as force and pressure or the like to modulate its wavelength. The measured clearance is calculated by the variable gap Fabry-Perot interferometer and the signal processing part in the optical sensor and further the physical quantities are measured.

An on line test method and test system of differential type temperature-compensating bridge rope force based on the magnetoelasticity is disclosed. The bridge rope is the ferromagnetic material and placed in the specific magnetic field, the bridge rope will be magnetized; the magnetic conductivity of bridge rope will change with the variety of stress condition and temperature. The sensor comprises operating magnetic circuit and reference magnetic circuit, in every designing of the magnetic circuit, the bridge rope is just a part of the magnetic circuit and not as the iron core of the actuating coil and the measuring coil. The reference magnetic circuit of sensor just feels the changes of temperature, but the operating magnetic circuit feels the changes of temperature and rope force, the output signal of the operating magnetic circuit and the reference magnetic circuit is differential to eliminate the temperature effect, the value of rope force can be tested with the corresponding relationship between the change of magnetic conductivity and rope force. The test method of rope force in the invention characterized in high accuracy, well dynamic response, low price of sensor, convenience of mounting and conditioning, long service life, strong overcurrent protection power, fitting for static and dynamic measurement, sampling just in time in all-weather, the testing results are free of effects of anticorrosive coating and protective plastic casing which is in surface of bridge.

The invention provides a method and device for measuring the low concentration sludge settling rate at turbulent motion. The image of sludge is processed to obtain sludge measuring data. The image acquiring device is connected with the measuring computer by the data line. The measuring computer comprises: an image acquiring module, an image processing module and an image measuring module. The image measuring module operates based on the acquired data from the image processing module to obtain the data of the tested sludge and comprises a sludge grain size measuring sub-module for calculating the average diameter of the sludge image based on the acquired sludge image from the image processing module to calculate the real average diameter of the sludge image based on the scaling proportion; a sludge settling rate measuring sub-module for calculating the rate of the sludge on the image based on the two frame image obtained from the processing module and calculating the real sludge settling rate based on the scaling proportion. The invention has features: high precision of measuring result, quick measurment, easy usage and automatization.

The invention discloses a multi-camera measurement method based on a refractive projection model and a beam tracking method, and used for the field of visual detection and image measurement. The process of the present invention comprises the following steps of: building a multi-camera system; global calibrating by multi-camera based on the refractive projection model and the beam tracking method;respectively capturing images from different directions by a plurality of cameras; extracting and matching features to obtain measured three-dimensional points; converting the three-dimensional pointsobtained by each subsystem into the same coordinate system to obtain global measured data; and using the obtained three-dimensional point data to calculate an indirect amount (e.g., strain, displacement). The key of the present invention is the calibration of the multi-camera system, the result will affect the subsequent three-dimensional point acquisition. According to the multi-camera measurement method based on the refractive projection model and the beam tracking method, the features in the measurement process are that the multiple cameras in the system can be calibrated at the same timeto solve the problem that a planar calibration plate limits the distribution of multiple cameras, and the measurement process is flexible.

The invention discloses a steel ball grinding crack detection method based on neighborhood gray level similarity. The method specifically includes the following steps that 1, a grinding crack image of a steel ball is acquired and read into a computer; 2, if the acquired grinding crack image is a color image, a step 3 is performed and if the acquired grinding crack image is a gray level image, a step 4 is performed; 3, graying is performed on the color image F; 4, a neighborhood gray level average figure M of the gray level grinding crack image f is calculated; 5, a neighborhood gray level deviation value of pixels is calculated; 6, binaryzation is performed on a neighborhood gray level deviation figure S; 7, fragment removal operation is performed on a neighborhood gray level similar figure L; 8, cavity filling operation is performed on a gray level similarity grinding crack figure D; 9, morphological opening operation is performed. According to the method, a grinding crack area of the steel ball can be detected rapidly, and accordingly the diameter of a grinding crack can be worked out directly.

The invention provides a device and method for accurately measuring the concentration of low-concentration dusts, and belongs to the technical field of charge induction test. The structure of the device for accurately measuring the concentration of low-concentration dusts comprises a test channel, a charge induction assembly stretching into the test channel, and an airflow driver and a processingdisplay which are matched, the front end of the test channel is connected with a trumpet-shaped air inlet tube, the rear end of the test channel is connected with a trumpet-shaped diffusion tube and an airflow driver, and airflow sequentially goes through an air inlet tube, the test channel and the diffusion tube to form the Venturi effect. The detection device has the advantages of simple structure, wide measurement range, high precision of a measurement result especially when the concentration of the dusts is low, and small repetition error. The detection method can highly-efficiently and accurately test the concentration of low-concentration dust airflow, has a high precision, allows the concentration of the dusts to be directly tested through checking meters by establishing an experience database by means of a model, and is widely suitable for every measurement environment.

The invention discloses an automatic production system of a chain. The automatic production system comprises an automatic assembling device, an automatic detecting device, an automatic head riveting device, an automatic pretensioning device, an automatic oiling device and an automatic packaging and boxing device, all of which are sequentially arranged in the chain advancing direction. The automatic pretensioning device comprises a pretensioning mechanism, a detecting mechanism and a control mechanism, the pretensioning mechanism and the detecting mechanism allow the chain to penetrate in sequence, and the control mechanism is connected to the pretensioning mechanism and the detecting mechanism in a communication manner. The tension with the adjustable magnitude is provided by the pretensioning mechanism to tension the chain. The detecting mechanism is used for detecting the tensioning state of the chain. The control mechanism receives signals about the tensioning state of the chain from the detecting mechanism and indicates the pretensioning mechanism to adjust the magnitude of the tension according to the signals. The system is convenient to operate and high in automation degree, the tension can be detected and adjusted in real time in the pretensioning process, and the production efficiency and the product percent of pass are effectively improved.

The invention belongs to the technical field of optoelectronics and measurement, and particularly relates to a method and a device for measuring frequency stability of single-frequency pulse laser. The method includes taking a reference light source with high stability as a frequency standard, allowing the reference light source to generate certain frequency shift relative to a to-be-measured light beam, and beating with the to-be-measured light beam to acquire information of frequency stability of the to-be-measured single-frequency pulse laser according to frequency information of beat frequency signals. The device is simple in structure; the method utilizing the device has good real-time performance and high measurement precision, completes real-time measurement of frequency stability of the single-frequency pulse laser, and scientifically solves problems of high design difficulty in frequency stability measurement of the single-frequency pulse laser and high measurement error caused by shake of measuring systems.

The invention is applicable to the field of detection for the air permeability of tipping paper and provides an online detection system and method by laser perforation on tipping paper. The system comprises an image sensor and a back light plate which are oppositely placed, wherein the tipping paper to be detected is arranged between the image sensor and the back light plate; and micropores are perforated in the surface of the tipping paper according to the requirement. The system also comprises a computer connected with the image sensor, wherein the image sensor is used for capturing a micropore arrangement image on the surface of the tipping paper; and the computer is used for calculating the total area of the micropores in the micropore arrangement image and calculating the air permeability value of the tipping paper to be detected according to a calibrated area-air permeability relation. The online detection system and method provided by the invention have the advantages that the photoelectronic imaging is adopted, the air-permeability value is calculated according to the total area of the micropores, the accuracy of a measurement result is high, the measurement time is short and the production efficiency is high; and the structure is simple, the implementation is easy, and the measurement efficiency and the measurement accuracy can be improved, so that the application value is extremely large.

The invention discloses a camera horizontal plane inclination angle measuring method and device, and belongs to the field of precision measurement and image processing. According to the invention, a motor controls a working platform to move so that a calibration plate graph enters the visual field of the camera, the proper position of the calibration plate graph in the visual field of the camera is adjusted, the image of one calibration plate graph is shot, and then the Y-axis of the motor is kept still and moves along the X-axis of the motor for a certain step length to shoot the image of the other calibration plate graph; because the camera has an inclination angle when being installed on the horizontal plane, the coordinate values of the common area points in the two calibration plate graphic images are different, and the inclination angle of the camera on the horizontal plane can be obtained by processing the two shot images. According to the method, the calibration plate pattern manufacturing precision is high, and the working platform movement control precision is high, so that the calibration precision of the camera horizontal plane inclination angle is high, the step size can be changed for calibration of different camera views and different movement ranges, and the method is high in adaptability.

The invention, which belongs to the field of testing of a special propulsion ship model, particularly relates to a nozzle flow PIV test device and method of a water-spray propulsion ship model. The device comprises a water-spray propulsion ship model and an adjustable underwater PIV measuring system. The water-spray propulsion ship model includes a body model, a water spraying propeller nozzle anda water spraying propeller flow channel; the water spraying propeller flow channel is installed inside the body model; the water spraying propeller nozzle is installed at the edge of the body model;and the water spraying propeller nozzle and the water spraying propeller flow channel are connected. The adjustable underwater PIV measuring system includes a measuring cross section, a PIV lightningbody, a PIV connecting rod, a laser sheet light source, a front end camera, and a rear camera; the front end camera and the rear end camera are fixed inside the PIV lightning body; the PIV connectingrod is fixed above the PIV lightning body; the laser sheet light source is fixed inside the PIV lightning body and is arranged at the same side of the front end camera; and the measuring cross sectionis fixed at the lower surface of the PIV lightning body.

The invention provides a target radar wave scattering hot spot full-automatic measurement and diagnosis device and method. The device comprises an intelligent walking trolley, a target radar scattering hot spot measurement system, a laser radar and a plurality of omnidirectional laser targets; wherein the intelligent walking trolley is provided with an embedded computer and can freely walk and stop in a plane according to a specified path; the target radar scattering hot spot measurement system and the laser radar are installed on the intelligent walking trolley, and the distance to each omnidirectional laser target is recognized and precisely measured. And the upper end reflecting surface of the omnidirectional laser target is covered with a laser high-reflectivity material, and a vertical ranging function is achieved. According to the invention, the positioning precision and efficiency of the target radar scattering hot spot measurement system are improved, the measurement cost is reduced, human interference caused by activities of personnel in a test site is avoided, and the precision of a target radar wave scattering hot spot measurement result is improved. The device is suitable for indoor and outdoor target radar wave scattering hot spot measurement environments.

The invention discloses a frictional force measuring method for a sliding block on a horizontal linear guide rail. The frictional force measuring method includes that a pulley presses a hanging rope and drives the hanging rope to move together, the hanging rope receives the pressure from the pulley, an included angle theta is formed between the hanging rope and a plumb line, and the horizontal component of the pressure of the pulley to the hanging rope is Gsin theta; the pulley is controlled to move along the direction of the horizontal linear guide rail constantly, the sliding block moves along the offset direction of a weight when a certain numerical value is reached, the net offset of the weight when the sliding block starts to slide is recorded, an included angle theta' is formed between the hanging rope and the plumb line at the moment, the horizontal component of the pressure of the pulley to the hanging rope at the moment is calculated to be Gsin theta', and the force value is identical to the frictional force value of the sliding block. The frictional force measuring method has the advantages of simplicity, capability of rapidly measuring the frictional force between the sliding block and the contact surface thereof, high measuring result accuracy, high measuring efficiency and applicability to frictional force measurement of sliding blocks in the high-accuracy hanging field.

The invention discloses a static liquid level based liquid level alarm switch detection method and alarm line calibration method. The method includes that quantitative liquid is filled in a liquid storage container, and a float of an installed liquid level alarm switch to be detected floats in the liquid; a drive device drives the liquid level alarm switch arranged on an installation rack to riseor drop so as to drive the float of the liquid level alarm switch to rise or drop; when a position of an alarm line of the liquid level alarm switch is reached, i.e., an opening/closure state of the liquid level alarm switch is changed, a vertical lifting device is automatically or manually controlled to stop rise or drop; a distance measurement device is used to measure a calibration parameter ofthe liquid level alarm switch alarm line. The static liquid level based liquid level alarm switch detection method and alarm line calibration method can visually detect if the liquid level alarm switch works normally or not, can accurately calibrate a position of the liquid level alarm switch, is high in accuracy, and is easy and fast to operate.

The invention discloses a measurement clamp for an X-CT (X ray-Computed Tomography) system and belongs to the field of testing clamps. The measurement clamp comprises a sample platform, a sheet carrying column and an adhesive sheet, wherein a positioning concave platform matched with a scanning rotary platform is arranged on the bottom surface of the sample platform; the lower part of the sheet carrying column is fixedly connected with the sample platform; a rotary shaft of the sheet carrying column is parallel to a rotary shaft of the sample platform; the middle part of the sheet carrying column is a column body and the upper part of the sheet carrying column is a transparent thin plate which is arranged on the top surface of the column body and is integrated with the column body; the adhesive sheet is used for sticking a device to be detected and is arranged on the surface of the transparent thin plate. According to the technical scheme, phase displacement is not generated by the transparent thin plate relative to the sample platform, so that displacement is not generated on a tiny device; a measurement result is accurate and reliable; meanwhile, the attenuation on X rays is reduced by the transparent thin plate; a structure for highly accurately measuring the tiny device by utilizing X-CT is realized and the testing clamp appears in the field of the tiny device for the firsttime .

The invention discloses an online measuring method and device for a cutter radius compensation value of a numerical control milling precision inferior arc, and the method comprises the steps: placing a standard block with a groove on a workbench, determining an auxiliary circle through a measuring needle in a lever indicator, and enabling the auxiliary circle to be tangent to the midpoint of the inferior arc; determining a corresponding X value and a corresponding Y value according to the origin coordinate value of the inferior arc and the center coordinate value of the auxiliary circle; moving the machine tool workbench to enable a machine tool spindle to reach the center position of the auxiliary circle; then moving a machine tool spindle to enable a measuring needle in the lever indicator to be in contact with the inferior arc, recording the grid degree of the dial plate deviating from the zero position, and calculating the actual radius of the inferior arc through the recorded grid degree; and finally, calculating the actual radius and the theoretical radius of the inferior arc, and calculating a corresponding compensation value according to the machining precision of the inferior arc. The online measuring method and device have the advantages of being simple in structure, convenient to operate and use, capable of improving the machining efficiency and precision, high in practicability and suitable for application and popularization.

The invention provides an ultrasonic probe device and a workpiece sound velocity measuring method. The ultrasonic probe device comprises a first transverse wave probe, a second transverse wave probe and a measuring scale. The first transverse wave probe and the second transverse wave probe are both arranged on the measuring scale in a sliding mode, and the incident angles of the first transverse wave probe and the second transverse wave probe are the same. The first transverse wave probe and the second transverse wave probe adopt a one-transmitting and one-receiving mode. According to the invention, the first transverse wave probe and the second transverse wave probe are arranged on the measuring scale in a sliding manner, and the distance between the incident points of the two transversewave probes is measured through the measuring scale; one transverse wave probe is used for transmitting ultrasonic transverse waves to a to-be-detected workpiece, and the other transverse wave probe is used for receiving reflection echoes reflected by the to-be-detected workpiece; and the sound velocity in the to-be-detected workpiece is detected according to the distance between the incident points of the two transverse wave probes and the propagation time of the ultrasonic transverse waves in the to-be-detected workpiece, the thickness of the to-be-detected workpiece does not need to be obtained in the detection process, the requirement for detecting the sound velocity of a workpiece with unknown thickness is met, and the accuracy of the measurement result is high.

The invention discloses an inertial navigation pose precision adjusting and mounting device for an unmanned aerial vehicle, the device can quickly and effectively adjust the mounting precision of inertial navigation equipment of the unmanned aerial vehicle and is accurately connected with a fuselage frame plate. A horizontal adjusting screw of the inertial navigation pose adjusts the height of a bottom plate through a thread pair, a course adjusting rod is installed in a steering groove in the center of an inertial navigation installation sample plate, the course adjusting rod rotates to drive a gear ring in the steering groove to rotate, and course adjustment of the inertial navigation installation sample plate is achieved. The precision grade of a course indication rod of the inertial navigation installation sample plate meets the horizontal measurement requirement of the unmanned aerial vehicle for an optical level meter and an optical theodolite, and the minimum measurement resolution of the electronic digital display gradienter is higher than the inertial navigation installation precision requirement. The inertial navigation pose precision adjusting and mounting device is simple in structure and convenient to operate; the device is suitable for unmanned aerial vehicles of various types and sizes, facilitates maintenance and use, is high in measurement result precision and convenient to read, guarantees the navigation precision of the unmanned aerial vehicle in the flight process, and provides guarantee for the unmanned aerial vehicle to complete flight tasks.

The invention discloses an oscillatory wave test system which comprises a pulse generator, a Marx main topology circuit, an output control module and a low-voltage direct-current power supply module; the Marx main topology circuit adopts a full-bridge inversion topological structure and is used for determining the working state of the pulse generator; the output control module is used for controlling the working state of the Marx main topology circuit; the low-voltage direct-current power supply module is used for supplying power to the pulse generator; the partial discharge detection circuit is used for acquiring an oscillation voltage signal and a partial discharge signal of a detected cable; and the control module is used for sending a control instruction to the pulse generator and processing the received oscillation voltage signal and the partial discharge signal. By adopting the bipolar high-voltage repetition-frequency square-wave pulse generator, disturbance caused by switching action and complexity of oscillation inductance matching and waiting for constant-current source charging are avoided, and the test system has the advantages of being easy to control, small in size, low in cost, short in measurement time and high in precision.