250results about How to "Large measuring range" patented technology

The invention discloses a dTOF laser radar-based berth detection system and method, and relates to the technical field of intelligent transportation, and the system comprises an image collection module which is used for collecting a berth image through a camera; the data processing module is used for preprocessing the parking space image and analyzing image data through an image recognition algorithm; the berth detection module is used for detecting the berth state through the dTOF laser radar; and the GPS positioning module is used for determining the real-time position of the inspection equipment. According to the technical scheme of the invention, the method can achieve the recognition of the temporarily-parked vehicle near the parking space, avoids the wrong charging of the temporarily-parked vehicle through the inspection equipment, and is higher in application value.

The utility model relates to the technical field of pile foundation construction, and discloses a pile foundation hole depth measuring device for pile foundation construction, which comprises a mounting rack, the upper surface of the mounting rack is provided with a positioning groove extending out of the lower surface of the mounting rack, and the mounting rack is slidably sleeved with a positioning block through the positioning groove. The upper surface of the positioning block is provided with a sliding groove extending out of the lower surface of the positioning block, a fixing block is slidably arranged in the sliding groove in a sleeved mode, and the fixing block is provided with a measuring mechanism, according to the pile foundation hole depth measuring device for pile foundation construction, the length of the fixing block extending downwards into the pile foundation hole is the current depth of the pile foundation hole, measurement is accurate, and the measuring efficiency is high. Compared with a traditional method that a plumb bob and a measuring rope are used for measuring, the plumb bob is prone to colliding with foreign matter on the side wall of the foundation pit when stretching into the foundation pit, the situation that the plumb bob is damaged, the measuring rope shakes and measurement is not convenient is avoided, the measuring accuracy of the pile foundation hole is guaranteed, and meanwhile the practicability of the measuring device is improved.

The invention discloses a high-precision laser gas detection system, and belongs to the technical field of laser spectrum gas detection. According to the invention, the reference signal feedback drives the laser to realize the locking of the laser output central wavelength. By arranging a half-optical-path sampling hole, double-path acquisition of half-optical-path and full-optical-path interference signals is realized, and when an absorption signal of a full-optical-path digital signal is smaller than a set threshold value, laser fluctuation noise, front half-optical-path interference noise and photoelectric detector noise are eliminated by adopting a double-path signal comparison method; and the interference waveform of the absorption region of the rear half optical path is fitted by combining the light interference Airy model function through the interference signals of the two-wing non-absorption region of the double-path comparison signal, so that the interference noise of the rear half optical path is eliminated, and the measurement precision of the to-be-measured gas at low concentration can be further improved. When the absorption signal of the full-optical-path digital signal is larger than or equal to a set threshold value, the measurement range can be directly and effectively increased by adopting the half-optical-path signal, and the wide-range measurement range is achieved while high-precision measurement is met.

When the water level detection device is used, the base is fixed on a riverbed, the density of the graduated scale is smaller than that of a water body, so that the graduated scale can be automatically in a vertical state in the calm water body, the graduated scale can be scratched through the first through hole in the downward moving process of the floating body, and the graduated scale can be scratched through the second through hole in the upward moving process of the floating body. When the water level needs to be determined, the graduated scale can be scratched through the second through hole, so that numerical values on the graduated scale are clearer and not easy to misread, the measuring result can be more accurate by matching with the floating body which is not easy to be influenced by water surface fluctuation, and the scale value of the graduated scale corresponding to the floating body can be observed through the camera device when the water level needs to be determined; as the graduated scale is composed of a plurality of detachable rod pieces, the number of the rod pieces can be adjusted, so that the length and the measuring range of the graduated scale are adjusted, and the graduated scale is convenient to carry after being detached; in general, the water level detection device is larger in measurement range and more accurate in measurement result, and the graduated scale is convenient to carry and can be automatically in a vertical state in a calm water body.

The invention discloses a method for realizing intelligent millimeter-level elevation measurement based on a laser technology, which comprises the following steps of: navigating to a measurement point by an intelligent navigation robot according to a measurement task, adjusting a horizontal platform to a horizontal state, and enabling a two-dimensional coordinate of an RTK (Real-Time Kinematic) module to be equal to a two-dimensional coordinate of the measurement point; the intelligent navigation robot drives the light source mounting rod to rotate through the horizontal turntable, so that the laser transmitter searches and aims at the axis of the laser receiving reference rod to project horizontal laser; the AIOT platform notifies the reference rod to move to receive the laser, records a moving distance value output by the incremental encoder and uploads the moving distance value to the AIOT platform; a laser distance measuring sensor is turned on to emit vertical laser to a measuring point, and the measured distance is output and uploaded to the AIOT platform; and the AIOT platform calculates the millimeter-level elevation of the measurement point where the intelligent navigation robot is located through an expression. According to the invention, millimeter-level elevation measurement and automation and digitization of measurement operation can be realized.

The invention belongs to the field of composite material manufacturing, and relates to a manufacturing method of a composite material box-shaped beam with closed-angle ends. The composite material cover plate of the composite material box-shaped beam can be manufactured, and the structural form of the composite material cover plate can well act on curing forming of the composite material box-shaped beam. According to the invention, the manufacturing of the composite material box-shaped beam, the inspection of the axial direction size, the inspection of the profile size and the like can be realized. The invention innovatively provides a metal joint structure to replace a commonly used metal hinge support arm, and the metal joint structure has a function of measuring the profile precision of the inner profile of the edge strip of the composite box-shaped beam. The invention innovatively provides a split combined type forming tool and a measuring tool, and realizes a manufacturing process method of the composite material box-shaped beam with the closed angle at the end part. The measuring tool is innovatively provided, the measuring tool can measure the axial direction size of the composite material box-shaped beam, and the measuring range is large.

The invention discloses a machine tool cutter space pose on-machine measurement device and a measurement method thereof, and the device comprises a calibration module which is installed at one side of a cutter handle of a cutter; a frequency-modulated continuous wave laser interference system and a galvanometer are installed on a vibration isolation workbench of the machine tool, light beams emitted by the frequency-modulated continuous wave laser interference system achieve conversion of a set angle through the galvanometer so as to cover the calibration module, and a space positioning algorithm is adopted to fit the plane where the target ball is located. And obtaining a deviation value between the mass center and the normal vector in two measurement results before and after machining, and taking the deviation value as the tool space pose error before and after machining of the machine tool, so that rapid and high-precision direct measurement of the tool space pose error is realized. The method has the advantages of being large in measurement range, high in measurement precision, simple in structure and low in cost, and the defect that in an existing method, the position and pose errors of the tool are indirectly calculated through an error model is overcome.

The present invention relates to the technical field of ship fuel tank monitoring, and discloses a sensor for measuring the liquid level position in a ship fuel tank and a working method thereof, that is, the sensor comprises a mounting mechanism, a protective tube, a rectangular partition, a first capacitance measuring probe, a second capacitance measuring probe and a processing module, the second capacitance measuring probe is wrapped by an insulating layer and the bottom end position of the second capacitance measuring probe is lower than the bottom end position of the first capacitance measuring probe, so that after the sensor is installed, based on conventional capacitance detection and liquid level height measurement principles, according to the fitting function of calibration data and two capacitance measurement values ​​collected and obtained by two capacitance measuring probes of different lengths, the fuel liquid level position and the oil-water interface position corresponding to the two capacitance measurement values ​​can be determined, so as to achieve the purpose of monitoring the water intrusion on the bottom of the tank and measuring the fuel level at the same time, thereby improving the safety of ship operation and the anti-damage management capability, and is particularly suitable for use in the field of unmanned ships.

The invention relates to the technical field of multi-phase flow measurement, in particular to a two-stage separation flow measurement system based on a small GLCC and an ERT, and can solve the problems that when two existing methods are independently used, the flow measurement range is small, the generalization ability is poor and the like, the complex and changeable flow conditions of an oil field cannot be adapted to, and the measurement accuracy is high to a certain extent. And the optimization of a measurement result often needs a complex data processing technology, so that the measurement is difficult and inaccurate. The single-stage separator comprises a separation chamber, the separation chamber is of a cylindrical structure, an inlet of the separation chamber is connected with a system inlet, a liquid outlet of the separation chamber is connected with a system outlet, a gas outlet of the separation chamber is connected with the second-stage separator, the second-stage separator is designed based on a small-sized GLCC, and the sensor is arranged in the separation chamber. A gas outlet and a liquid outlet of the secondary separator are respectively connected with a system outlet; the sensor comprises a flow meter and an ERT.

The invention relates to an optical fiber sensing system and an optical signal demodulation method. The optical fiber sensing system comprises a plurality of optical fiber sensors; a light source emitting a light signal; the optical transmission module is used for dividing the optical signal into multiple paths of first sub-signals and inputting the first sub-signals into the optical fiber sensors, and is also used for receiving multiple paths of second sub-signals returned by the optical fiber sensors and coupling the second sub-signals to the optical demodulation module; the optical demodulation module comprises a plurality of sub-demodulation units, and one sub-demodulation unit is used for demodulating one path of second sub-signal; the sub-demodulation unit comprises a first photoelectric sensor, a second photoelectric sensor with a first filter and a third photoelectric sensor with a second filter, and the filtering wavelengths of the first filter and the second filter are different. Through the design that the first filter plate and the second filter plate filter wavelengths, the measuring range of the optical fiber sensing system is expanded to the combination of the first filter plate and the second filter plate, so that the purpose of increasing the measuring range is achieved.

The embodiment of the invention provides a self-calibration method of a space manipulator. The self-calibration method comprises the following steps: establishing a kinematic model of the space manipulator based on an improved Denison-Hartberg method (MDH); a tail end pose error model of the space manipulator is obtained through the kinematic model; obtaining the motion range of the hand-eye camera according to the measurement precision, the field of view of the hand-eye camera and the visual target parameters; according to the motion range of the hand-eye camera, distribution information of all measurement sub-areas in the working space of the space manipulator is obtained; and kinematics parameter calibration values of the space manipulator are obtained according to the tail end pose error model and the distribution information of the measurement sub-areas. According to the self-calibration method provided by the embodiment of the invention, error data in a larger measurement range can be obtained, and the calibration precision of kinematics parameters and the globality of a calibration result are improved.

The invention provides a system and a method for high-precision synchronous real-time measurement of a temperature field and a deformation field. The system comprises a laser modulation assembly, wherein a collimated laser beam emitted by the laser modulation assembly is incident to the optical surface of an object to be measured through a prism assembly; a laser reflection beam reflected by the optical surface of the to-be-measured object is in a collimation state and is reflected to the polarization measurement assembly through the prism assembly; an infrared band light beam emitted by the optical surface of the to-be-measured object is transmitted to the infrared thermal imaging device through the prism assembly for imaging; the polarization measurement assembly converges interference beam results of the laser reflection beams into diffraction spots; the image acquisition and processing system is arranged at the downstream of the filtering lens along the light path direction of the laser reflected light beam and is used for acquiring laser image diffraction spots and carrying out polarization phase shift to carry out coherent gradient sensing measurement and post-processing calculation; and an image formed by the infrared thermal imaging device is processed by the image acquisition and processing system. According to the invention, real-time accurate synchronous measurement of the temperature field and the deformation field of the to-be-measured object can be accurately and effectively realized.

The utility model discloses glass thickness measuring equipment for building curtain wall detection, which comprises a machine body, a transverse electric lead screw slide rail and a thickness measuring machine shell, and vertical electric lead screw slide rails are arranged at two ends in the machine body. According to the utility model, the transverse electric lead screw slide rail and the like are installed, so that when the device is used, the vertical electric lead screw slide rail, the transverse electric lead screw slide rail and the longitudinal telescopic cylinder are started to drive the thickness measuring structure connected with the vertical electric lead screw slide rail, the transverse electric lead screw slide rail and the longitudinal telescopic cylinder to be flexibly adjusted in a three-dimensional direction along a glass product; therefore, continuous thickness measurement of a plurality of positions on the glass product can be realized conveniently, whether the thickness of the glass product is uniform or not can be measured conveniently, and furthermore, the thickness measurement structure can be driven by the motor and the angle sensor to automatically and vertically overturn by 90 degrees. Therefore, measurement conversion of the thickness measuring head structure between the long edge and the wide edge of the glass product can be realized, the measurement range is expanded, and thickness measurement of different side edges of the glass product can be realized.

The invention discloses a three-dimensional shape reconstruction system combined with a grating inversion technology and a sensor preparation method, and belongs to the technical field of optical fiber sensing. The system comprises a shape sensor, a grating demodulation device and a shape reconstruction device, an optical fiber bundle formed by a plurality of optical fiber grating strings or a multi-core optical fiber is attached to the outer side of the base material, but is not completely bonded, and is only subjected to point constraint to form a shape sensor; the demodulation device acquires spectral information in real time; the reconstruction device is combined with a spectrum inversion technology to restore and display a three-dimensional shape with high precision. The invention also comprises a manufacturing method of the shape sensor. The method comprises the following steps of: 1, manufacturing the optical fiber bundle or the multi-core optical fiber; secondly, the optical fiber bundle is arranged in a hollow hose bonded to the side edge of the base material, and only one end of the optical fiber bundle is fixed; the problem of low spatial resolution in the fiber bragg grating shape sensing technology is solved, meanwhile, the shape sensor structure can eliminate strain on the outer side of the base material when the base material is bent, and the optical fiber is protected.

The invention relates to a calibration method for a large-view-field three-dimensional fusion two-dimensional visual detection system, which comprises the following steps of: calibrating parameters of the large-view-field three-dimensional fusion two-dimensional visual detection system based on a visual calibration target, a standard ball bat and a laser tracking three-dimensional measurement system, and calibrating internal and external parameters of a camera and a light source projector through the visual calibration target; calibration of a large-view-field splicing matrix is performed through a laser tracking three-dimensional measurement system, and calibration results can meet three-dimensional and two-dimensional detection requirements of a visual detection system at the same time, so that full-range misloading and neglected loading detection of the honeycomb sandwich structure plate of the spacecraft based on point cloud comparison and contour comparison is realized, and detection requirements of different measurement objects are met.

The invention relates to the field of land area measuring devices, in particular to a geographic information land area measuring device. The device comprises a plurality of measuring units which are connected in series for use; the measuring unit comprises a supporting column, a connecting storage cylinder, a guide belt, a laser measuring assembly, a guide piece and a data collector. The connecting storage cylinder is located on the supporting column. One end of the guide belt is stored in the connecting storage cylinder, and the other end of the guide belt is connected with the adjacent connecting storage cylinder; the laser measuring assembly is located at the upper and lower ends of the connecting storage cylinder and comprises a laser emitting part and a laser receiving part; a plurality of groups of guide pieces are arranged along the guide belt and are provided with upper and lower guide windows for laser to pass through, and the upper and lower guide windows are used for guiding laser emission paths of the laser emission pieces at the upper and lower ends respectively; and the laser measuring assembly is arranged at the upper end of the data collector. According to the invention, the measurement units with different numbers and different connection modes are adopted for combined measurement, the measurement mode is flexible, convenient, accurate and efficient, the display is visual, and field land area measurement is facilitated.

The embodiment of the present invention provides a laser radar device, which includes: a transmitting device, a receiving device and a signal processing device; wherein the signal processing device is connected to the transmitting device and the receiving device respectively; the transmitting device is used to convert point-like emitted light into planar emitted light, and emit the planar emitted light to the target object; the receiving device is used to receive the planar reflected light reflected by the planar emitted light on the target object, and send the received planar reflected light to the signal processing device; the signal processing device is used to determine the characteristic information corresponding to the target object according to the planar reflected light. The technical solution provided by the present invention can improve the emission power of the planar emitted light, thereby expanding the measurement range, improving the signal-to-noise ratio of the laser radar, and thereby improving the measurement accuracy.

The utility model provides a measuring tool for circle center positioning, and relates to the technical field of machinery, and the measuring tool comprises a pair of first connecting plates with one ends rotatably connected, the first connecting plates are provided with measurement scales along the length direction, and the first connecting plates are used for simulating any chord of a circle to be measured; each first connecting plate is slidably connected with a second connecting plate in the direction perpendicular to the length direction of the first connecting plate, and straight lines where the two second connecting plates are located can intersect at one point. Each second connecting plate is provided with one first light beam emitter, and the first light beam emitters are used for projecting light beams in the linear direction where the second connecting plates are located. According to the technical scheme, by simulating the chord and the vertical bisector of the circle to be measured and utilizing the light beam projection technology, the position of the circle center can be accurately found, limitation of the tool size can be avoided, and the measurement range is expanded.

The utility model discloses a measuring tool for multi-angle measurement, which comprises a triangular measuring tool, a ruler measuring tool and a rotating wheel, a step groove is arranged on the back of the triangular measuring tool, the rotating wheel is sleeved on the step groove, the bottom of the rotating wheel is embedded in the inner side of the step groove, and the ruler measuring tool is arranged on the surface of the rotating wheel through a bolt. The multifunctional ruler has the advantages that the structural design is reasonable, the triangular measuring tool and the ruler measuring tool are matched with each other, multi-angle measurement and graph drawing can be achieved, the ruler measuring tool is provided with different types of graduated scales, and drawing is more flexible and convenient.

This invention discloses a miniature flow sensor and an on-chip constant temperature difference control circuit for the flow sensor. The circuit includes a first resistor, a second resistor, an ambient resistor, an adjustable resistor, a micro-heater, an operational amplifier, a start-up resistor, and a start-up power supply. The ambient resistor and the micro-heater have the same temperature coefficient. One end of the first resistor is connected to one end of the second resistor and the output terminal of the operational amplifier. The other end of the first resistor is connected to one end of the start-up resistor, one end of the adjustable resistor, and the positive input terminal of the operational amplifier. The other end of the second resistor is connected to one end of the micro-heater and the negative input terminal of the operational amplifier. The other end of the start-up resistor is connected to the positive terminal of the start-up power supply. This constant temperature difference control circuit effectively maintains a constant overheating temperature of the micro-heater, thereby achieving a wide measurement range, low power consumption operation, and suppressing drift caused by ambient temperature, significantly improving the accuracy of the measurement results.

The application discloses a small shield machine pose detection device and method in curved pipe curtain construction, a one-dimensional workbench is initially at the highest point of a guide rail through the gravity of a heavy hammer, the guide rail is vertically installed on a jacking mechanism rack, and a long grating displacement sensor measures the vertical displacement coordinates of the one-dimensional workbench in real time. In the construction process, a cross joint measurement module passes through a pipe joint, a convex flange one end is connected with a concave flange at the tail of the shield machine, the concave flange one end is connected with a convex flange at the bottom of the one-dimensional workbench, two circular grating angle sensors and a circular grating reading head are arranged on the cross joint, the rotation angle measurement of two mutually perpendicular axes of the cross joint is realized, a Bluetooth wireless transmission module reads the rotation angles of each joint at the same time, and the rotation angles are transmitted to a computer, the computer collects each data every moment, the position coordinates of the top end of the shield machine relative to a reference coordinate system are obtained through calculation, and the pose of the shield machine is detected in real time.

The invention provides an office table production size accurate measurement device, and relates to the technical field of size metrology, a measurement device body comprises a bottom layer measurement frame, a top layer measurement frame, a thickness detection assembly and a width detection assembly, a supporting shaft is welded to the top end of the bottom layer measurement frame, a rotating arm is welded to the top of the top layer measurement frame, and the thickness detection assembly and the width detection assembly are welded to the bottom layer measurement frame. A rotating arm is arranged on the supporting shaft, one end of the rotating arm is provided with a rotating ring, the rotating arm is arranged on the supporting shaft in a sleeving mode through the rotating ring, and a width detection assembly is welded to the tail end of one of the two top-layer measuring frames; according to the accurate measurement device, the thickness detection assembly is matched with the two measurement frames to directly detect the center thickness of the table board with blocking at the edge, the detection process of the thickness, the width and the flatness of the table top can be continuously carried out, the large-range detection efficiency is improved, the whole device is simple and convenient to disassemble and assemble, and the detection efficiency is improved. And the detected office tables can be quickly switched.

The invention relates to the technical field of underwater measurement, and discloses a calibration device for underwater measurement of stereoscopic vision equipment, which comprises metering plates fixedly mounted at two ends of a connecting frame, limiting columns are fixedly mounted at one ends, far away from the connecting frame, of the two metering plates, and first cameras are fixedly mounted in the limiting columns; the acquisition surfaces of the first camera and the second camera face upwards; a second camera with the collecting face facing the side where the limiting column is located is fixedly installed on the upper surface of the connecting frame. According to the invention, the approximate distance and the approximate size between the object and the device are calculated in a manner of comparing multiple groups of data, so that the measurement range of the device is increased.

The invention relates to an optical fiber sensor, in particular to a spiral solution concentration optical fiber sensor and a solution concentration detection device.The spiral solution concentration optical fiber sensor comprises an optical fiber core which comprises an input section, a fiber core body and an output section which are sequentially connected, and the fiber core body is in a spiral shape; the wrapping shell is integrally in a spiral shape and is arranged outside the optical fiber core in a sleeving mode, at least two inlets are formed in one end of the wrapping shell, and at least one outlet is formed in the other end of the wrapping shell; the outer surface of the wrapping shell is covered with a total reflection layer so as to realize efficient reflection of optical signals; a certain gap is kept between the wrapping shell and the optical fiber core so that liquid to be detected can flow. The invention has the advantages of high sensitivity, quick response, outstanding stability and extremely low liquid consumption.

This application provides a laser power detection device and laser processing equipment, relating to the field of laser power measurement and monitoring technology. The laser power detection device includes a focusing element, a first neutral density filter, a second neutral density filter, and a photodetector module arranged sequentially along the optical axis. The detection beam undergoes staged energy attenuation through the two neutral density filters before entering the photodetector module for power detection, thereby avoiding damage caused by direct high-power-density laser light incident on the photodetector module. The distance between the focusing element and the first neutral density filter is smaller than the distance between the first and second neutral density filters, ensuring that the detection beam incident on the first neutral density filter still maintains a large spot size, achieving low power density attenuation. Simultaneously, the focal point of the reflected light from the second neutral density filter is located on the side of the focusing element closer to the first neutral density filter. The reflected light, after being focused, diverges and is absorbed by the inner wall of the device, avoiding stray light crosstalk and ensuring the signal-to-noise ratio of the device.

The utility model relates to the technical field of forestry survey, in particular to a measuring auxiliary device for forestry survey, which comprises a main plate, a fixed block is fixedly mounted at the top of the main plate, a plurality of vertical plates are fixedly mounted at the top of the fixed block, the plurality of vertical plates are averagely divided into two groups, and round rods are movably embedded in the two groups of vertical plates. The telescopic leg is adjusted to a proper position, a sliding block is pushed to enable a pushing column to be inserted into a circular hole of a limiting block, the telescopic leg is stretched, an inserting plate is rotated to a proper angle through a rotating cylinder, and an output shaft of a motor starts to rotate to drive a first belt and a second belt to rotate; the first belt and the second belt drive the two round rods to rotate through rotation, the round rods drive the round gears to rotate through force generated by rotation, the two round gears start to rotate and drive the moving column to be gradually lifted, and therefore the effect of adjusting according to the needed height is achieved, and the measuring range is enlarged.

The invention discloses a six-degree-of-freedom parallel device for large-range high-precision spatial pose measurement, and the device comprises a lightweight movable platform which is used for connecting a measured device; the lightweight fixed platform is used for connecting a fixed coordinate system; the plurality of precise spherical hinges are connected to the bottom of the lightweight movable platform; the plurality of measuring support leg assemblies are respectively connected to the plurality of precise spherical hinges; and the plurality of offset universal hinges are fixed on the lightweight fixed platform, the bottom of the measuring support leg assembly is connected with the offset universal hinges, and the offset universal hinges can provide rotation of at least two degrees of freedom. According to the six-degree-of-freedom parallel device for large-range high-precision spatial pose measurement, the spatial pose measurement cost is reduced, the environmental adaptability of spatial pose measurement is improved, the spatial pose measurement range is expanded, and the spatial pose measurement precision is improved.

The utility model belongs to the technical field of taper hole measurement, and particularly relates to a portable railway vehicle taper hole measuring instrument. The device mainly comprises two dial gauges which are respectively installed on a T-shaped workpiece, the T-shaped workpiece comprises a first installation rod and a second installation rod, and the dial gauges can be installed on a long-dimension section or a short-dimension section through fastening bolts and are used for measuring standard long and short taper holes. Besides, the first mounting rod comprises a fixed sleeve and a movable rod, and the movable rod can be inserted into the fixed sleeve and locked through a limiting knob so as to adapt to measurement of taper holes with different lengths. In order to meet the measurement requirements of different apertures, an extension rod can be installed on the measuring rod of the dial indicator. According to the utility model, the selected dial indicator has a Bluetooth wireless transmission function, so that manual intervention is reduced, and a worker can more intuitively know the measurement result of the taper hole. The device has the advantages of simple structure, convenient operation, high measurement precision and the like, and is suitable for on-site rapid measurement of railway vehicle taper holes.

This invention relates to the technical field of bridge expansion joint measuring devices, and discloses a bridge expansion joint measuring device and its measuring method, comprising: a fixed main handle, which is arranged in a hollow cylindrical shape; and an external probe measuring head, which is mirror-symmetrically arranged on both sides of the fixed main handle and movably arranged on both sides of the fixed main handle through a combined telescopic mechanism. Each external probe measuring head includes: a measuring base, which is coaxially arranged with the fixed main handle and has a diameter smaller than that of the fixed main handle. This device uses a first telescopic part and a second telescopic part in the combined telescopic mechanism to form a two-stage telescopic structure. The first telescopic part can automatically push the external probe measuring head outward after unlocking, which can meet the needs of rapid measurement of expansion joints of conventional width. When the width of the expansion joint exceeds the maximum stroke of the first telescopic part, the second telescopic part can be unlocked at the same time, and the fixed positioning plate and the entire external probe measuring head can be driven to further expand outward through the outer telescopic cylinder and the radial connecting rod, so that the measuring range is multiplied.

The present application relates to the field of space in-orbit close-range relative visual navigation technology, and particularly relates to a space target visual measurement method combined with acceleration drift estimation, a tracking spacecraft is provided with an acceleration sensor and a camera, S1: obtaining initial relative position information and relative velocity information through a measurement system, S2: obtaining acceleration values and space target images in real time; S3: establishing a relative motion equation, substituting the obtained acceleration values and the relative position and relative velocity information at the previous moment into the relative motion equation to calculate position information; S4: calculating an error amount, and estimating the errors of the relative position information, the relative velocity information and the acceleration values in the dynamic equation through a filtering algorithm according to the error amount to correct the calculation results obtained in the dynamic equation, so that accurate positioning of a target spacecraft can be realized.