2031results about How to "Avoid measurement errors" patented technology

A distortion generating sheet (22) intervenes between a first and a second flexible sheets (11) and (12), respectively, with one end (23) thereof fixed to the first sheet (11), and the other end (24) fixed to the second sheet (12). As a consequence, when a shear takes place across the first and second sheets (11) and (12), respectively, the shear is conveyed to the distortion generating sheet (22). A strain gauge (21) fixed to the distortion generating sheet (22) detects and measures the distortion generated by the shear in the distortion generating sheets (22). A third sheet (15) is further provided with its periphery bonded to the first sheet (11) to form a closed space. The force bearing the patient is measured by measuring the pressure in the space formed.

A visual detection device for parts mainly comprises an imaging system, an optical lens component, a lighting system, a mechanical adjusting system, a displacement detection system and a computer, wherein the imaging system consists of a CCD camera and an image acquisition card; the optical lens component consists of a lens body, an amplifying objective lens, and the like; the lighting system is respectively used for detecting surface defects and measuring topographic sizes; the mechanical adjusting system consists of displacement platforms used for adjusting the positions of the parts; the displacement detection system is used for recording the displacement distance of the displacement platforms; and the computer is used for recording and processing images. By shooting edge images of theparts through the imaging system and recording the displacement distance of the displacement platforms through the displacement detection system, the detection device calculates the topographic sizessuch as diameter, and the like, detects the surface defects of the whole spherical surface by the combined rotation of rotary tables, measures the defect sizes accurately, records the number of the defects and meets the two detection requirements of topography measurement and surface detection. By utilizing the visual microscopic detection technology, the device has high system resolution, good integrated performance and simple measurement process.

A 2-D three-frequency diphase measuring method based on colored- structure light includes preparing three gratings by complexing different three primary color sine light with three the same frequencies, projecting said gratings on object to be measured, utilizing two the same CCD vide cameras to make shooting for obtaining 24 pieces of pictures, dephasing said pictures to obtain phase values at X and Y direction on each pixel pf each picture and matching two phase values for calculating out 3-D coordinate of each point.

A torque-detecting sleeve member is a cylindrical member that has first and second cylindrical torque-acting parts, a torsion signal generator and a torsion converter. Torque acts on the first and second cylindrical torque-acting parts in at least two points. The torsion signal generator is disposed axially between the first and second cylindrical torque-acting parts to at least partially form an external peripheral surface between the first and second cylindrical torque-acting parts. The torsion converter is operatively disposed between the torsion signal generator and at least one of the first and second cylindrical torque-acting parts for converting torsion transmitted from the at least one of the first and second cylindrical torque-acting parts to the torsion signal generator.

The present invention provides for an apparatus and a method for determining a property of a fluid which flows through a biological tubular structure, such as blood flowing through a capillary vessel (112) under the skin (114). This enables in vivo non-invasive blood analysis. An objective (108) having a variable numerical aperture (116) is used to enable automatic detection of a blood vessel (112) and to provide a high signal to noise ratio of the return radiation for the purposes of the spectroscopic analysis and to provide a small detection volume that fits completely within the target region.

The invention provides a high-speed detection system and method of tunnel defects. The system comprises a master control unit, a linear laser, an area array charge coupled device (CCD) camera, an image compression unit, a displacement sensor, a synchronous controller, an image storage unit, a storage module, a correction module and an inertial navigator. A special measurement locomotive serves as a mobile monitoring platform for the design and is particularly suitable for subway tunnel monitoring, and subway and other tunnel space structures can be effectively, rapidly and dynamically measured; the actually measured data is compared with actual real distance, errors are analyzed, the parameter setting is adjusted, and the measurement accuracy is greatly improved; moreover, the XYZ axial vibration of the mobile monitoring platform is subjected to error correction through the inertial navigator, and a measurement error is prevented from being introduced into mobile measurement.

The invention belongs to the field of optical precision measurement and relates to a method and a device for measuring the appearance and the wall thickness of a sphere by combining a differential confocal confocal technology and point-diffraction interference. The method realizes the high-precision rapid measurement on the appearance of the outer surface of the sphere by using the point-diffraction interference, the rotation of the measured sphere and the splice of a measuring sub-aperture; and the appearance and wall thickness of the inner surface and the outer surface of a key area of a transparent or semitransparent sphere can be scanned and measured point by point by using the differentia confocal technology. The invention organically integrates a point-diffraction interference technology and the differentia confocal technology so as to realize the synchronous measurement on the appearance and the wall thickness of the inner surface and the outer surface of the sphere, and aims to solve the difficult problems that the traditional AFM or a single confocal sensor and the other scanning methods have low measuring speed, low efficiency, easy leakage in measurement and the like during measuring the surface of the sphere. The invention has broad application prospect in the fields of testing the appearance and the wall thickness of a laser fusion pellet, the appearance and the outline of a spherical surface and the like.

The invention is directed to a method of evaluating the signal of an infrared thermometer for measuring human body temperature, in which the infrared thermometer includes a probe adapted to receive thereon a probe cover or protective film sufficiently transparent to infrared radiation, and in which on a measuring operation performed with the probe cover or protective film in "installed" condition the signal is evaluated, so that a measuring operation is performed also when the probe cover or protective film is not installed, with an appropriate allowance being made for the consequently more intensive infrared radiation by different signal evaluation.

The invention relates to a friction stir welding head having a housing and a welding tool with a rotating welding pin and a rotating shoulder tool for welding workpieces which rest on a workpiece rest, with the shoulder tool, which rotates in synchronism with the welding pin, coaxially surrounding the welding pin. According to the invention, a first distance between a first laser rangefinder and a welding pin section 4a can be determined by means of the first laser rangefinder. This makes it possible to determine at least one change in the distance between the welding pin tip and the workpiece rest by means of a first laser rangefinder.

The invention discloses a temperature compensation method for a pressure sensor. In the method, the coupling error of a measurement system of the pressure sensor can be compensated inside the sensor, and external equipment directly reads a pressure numeric value. The method is simple to operate, and benefits the avoidance of measurement error caused by secondary sampling, and the reduction of the influence of system error and lag error on a gauge point by adopting a multi-calibration averaging method. A pressure compensation curve is fitted by using gauge point reliability analysis and taking variance as weight, and the fitted compensation curve is closer to a reliable gauge point, thereby improving measurement accuracy.

An automatic, frequency selective microwave tuner, used for load pull transistor testing, is capable of generating independently controllable reflection factors, both in amplitude and phase, at several, harmonic or not, frequencies simultaneously. The tuner employs horizontally and vertically adjustable high Q resonant probes and replaces, when used in harmonic load pull set-ups, otherwise required combinations of wide-band tuners with harmonic rejection tuners or wide-band tuners and frequency discriminators (diplexers or triplexers).

The invention relates to active passive knuckle arm type measuring robot. It includes I, II, III, IV, and V shaft assemblies. Its features are that each shaft assembly is set actuator and active passive switching unit; encoder used to measure output corner is connected with the output axis. The invention has high measuring accuracy, can actively process trace plan. The encoder can collect final moving corner for each knuckle axis to avoid mechanical error between step motor and harmonic reducer. The invention can be widely used in various products measuring and detecting.

The invention provides a quadrature calibration method and a quadrature calibration device of a triaxial vector magnetometer. The quadrature calibration device of the triaxial vector magnetometer quadrature is used for the alignment of a standard magnetic field and a reference direction in a quadrature calibration process of the magnetometer and comprises a shielding barrel, a solenoid coil, a cylinder-shaped probe installation platform and a working table. The shielding barrel is placed on the working platform, the solenoid coil is coaxially arranged by penetrating the center of the shielding barrel through a support, and the solenoid coil is used for providing the standard magnetic field. The solenoid coil is tightly stuck to the probe installation platform which is coaxially sleeved on the inner wall of the solenoid coil and the probe installation platform is movable and can be located in the inner portion of the solenoid coil and on an extension cord outside a solenoid coil axis. A groove which is used for placing a magnetometer probe is arranged in the center of the upper portion of the probe installation platform. The magnetometer probe is capable of moving as the probe installation platform along the extension cord outside the solenoid coil axis to an even magnetic field area in the inner portion of the solenoid coil in the calibration process.

The invention provides a celestial autonomous navigation method based on star sensors, which comprises the following steps: calculating attitude information based on a geocentric inertial coordinate system, which is output by a star sensor; calculating the optical axis direction based on the geocentric inertial coordinate system; converting the optical axis direction based on the geocentric inertial coordinate system into optical axis direction based on a WGS84 coordinate system; reading the included angles alpha 0 and beta 0 between the X and Y directions of the star sensor and the horizontal direction from a laser level meter; calculating the direction in the WGS84 coordinate system when the optical axis direction is perpendicular to the horizontal level; calculating the longitude alpha and latitude beta of the underground point S of the carrier; and outputting the attitude q and the longitude alpha and latitude beta of the underground point of the carrier in the geocentric inertial coordinate system. The invention avoids measurement and control errors caused by horizontal reference platforms, enhances the measuring accuracy, and simultaneously outputs the attitude of three axes and the longitude and latitude of the carrier in the geographic coordinate system in real time, thereby completely realizing celestial autonomous navigation.

An apparatus for measuring skin moisture content, the apparatus including: an electrode unit comprising a reference (R) electrode, a current (C) electrode, and a measuring (M) electrode; an operational amplifier including an inverting input terminal that is supplied to a first voltage and connects with the R electrode, and an output terminal that connects with the C electrode; a switch controlling a connection between the output terminal and the C electrode; and a comparison control unit comparing the first voltage with a voltage at the output terminal, and controlling the switch to connect the output terminal and the C electrode when the voltage at the output terminal is less than or equal to a value that is acquired by multiplying the first voltage and a predetermined constant.

The invention relates to a laser gas analyzer and a calibration method; wherein, the laser gas analyzer comprises a light source radiation unit used for generating semiconductor laser beams, a spectroscopy unit which respectively transmits the generated laser beams to a reference cell which is internally encapsulated by zero gas and gas to be measured with known consistency and a measurement cell where the gas to be measured is pumped into during the measurement process and the zero gas and end gas are respectively pump into during the calibration process, a reference detector which is used for obtaining the energy intensity of the laser beam which passes through the reference cell and positioning the absorption peak wavelength of the gas spectrum, and a measurement detector which is used for measuring the energy intensity of the laser beam which passes through the measurement cell and determining the gas consistency during the measurement process; and the calibration method combines the energy signals of the laser beams obtained by the two detectors with a specific arithmetic to carry out zero calibration and end calibration on the instrument. The laser gas analyzer has the advantages of wide application range, simple calibration operation process, saving time, reducing the production cost and usage cost and the like owning to the characteristics of sealed laser passage and multi-optical passages.

The invention provides a visual measuring device of a flame frontal surface structure of a movable fire source, and the visual measuring device comprises a control computer, a combustor, a turntable mechanism, an image acquisition device, a turntable driving device and a support seat, wherein the combustor is connected to the turntable mechanism; the turntable mechanism is arranged on the support seat; the turntable driving device is arranged in the support seat and connected with the turntable mechanism through a rotating shaft; the turntable driving device and the image acquisition device are respectively connected with the control computer; and the image acquisition device is connected with the turntable mechanism and arranged opposite to the combustor. The invention also provides a method for realizing the visual measurement of the flame frontal surface structure of the movable fire source through the device provided by the invention. According to the invention, the rotating speed of the combustor can be adjusted through a frequency conversion electromotor, the size of the flame which is generated by the combustor is controlled, the flame frontal surfaces of the fire source at various motion speeds and under combustion strengths are generated, and the device provided by the invention has the advantages of wide application range, simple structure as well as flexibility and convenience in operation.

The invention relates to large scale three-dimensional multifunctional geotechnical test machine. Its feature is that it includes mainframe part and container component. The former includes main frame, level xy directional and vertical weighted platform. The level xy directional weighted platform includes two perpendicular x and y directions weighted platform. The x directional weighted platform is set the bottom, can make the upper y directional one move along the x direction by x direction servo moving machine. The y direction weighted platform can make the loading bearing platform fixed on it move along the y direction by y direction servo moving machine. The vertical weighted platform is used to supply vertical pressure. The invention has good loading ability, can realize multi geotechnical test.

A device for performing distance measurements on an eye. The device includes an interferometer, focuses at least one measurement beam records backscattered radiation and interferometrically generates a measurement signal displaying structures of the eye by time-domain, spectral-domain or Fourier-domain coherence reflectometry, has an adjustment apparatus for laterally and / or axially displacing the focus in the eye or for varying a polarization state of the measurement beam and has a control apparatus which actuates the interferometer, wherein the control apparatus generates a plurality of A-scan individual signals from the backscattered radiation, combines these to an A-scan measurement signal and actuates the adjustment apparatus for displacing the position of the focus or for varying the polarization while recording the backscattered radiation from which the control apparatus generates the A-scan individual signals is being recorded.

Impurity is removed from gas, the resultant gas is introduced into a cell 15, and the intensity of light transmitted through the cell 15 is measured as a reference. Gas containing impurity of which concentration is known, is introduced into the cell 15, and the intensity of light transmitted through the cell 15 is measured with the temperature and pressure maintained at those used at the measurement of the reference light intensity. Then, the absorbance of the impurity is obtained according to the ratio of the two light intensity data obtained by the two measurements above-mentioned. The impurity absorbance thus obtained is stored, in a memory 20a, as a function of an impurity concentration. Gas containing impurity of which concentration is unknown, is introduced into the cell 15, and the intensity of light transmitted through the cell 15 is measured with the temperature and pressure maintained at those used at the measurements above-mentioned. The absorbance of the impurity is obtained according to the last-measured light intensity and the reference light intensity. The absorbance thus obtained is applied to the function, thereby to obtain the impurity concentration.

First, the method obtains the group of relation curves and fitting functions between the surplus energy and the open circuit voltage in the service time of lithium ion batteries. Based on the modified module value of the low frequency alternating current impedance, the one of the said curve or fitting function is selected. Based on the open circuit voltage and the selected fitting function, the surplus energy of the battery is calculated out. The device includes the cast and the internal circuit boards composed of interconnection of the microcomputer, the circuit for controlling the charge current, the amplification circuit for charging and discharging current signal, the current measurement circuit and thue pure oscillator etc.

The invention provides a closed-loop optical fiber current transformer, which comprises a light source, a light source control unit, a photoelectric detector, an optical device integrated assembly and a sensing head. An optical path system of the transformer is simple in structure and convenient in integration and modularization; a used optical element is small in volume and light in weight and free of electromagnetic interference, and has no interference on measured amount; and a reflection type optical path and a simple optical device are used for achieving mode interchange of orthogonal polarized light so as to form a reciprocity optical path and improve anti-interference capacity of the optical path. The multi-closed-loop technology is adopted, system measurement error caused by light source power attenuation and half-wave voltage drift of an optical is overcome, and stability and reliability of the transformer are improved.

The invention discloses a method for the calibration of vectorial coordinate transformation and the modification of errors of a digital image probe, and a device thereof; the noncontact optical measurement principle is adopted to realize the precise calibration and accurate modification of errors of the image probe in high-accurate two-dimensional measurement and ensure an accurate measurement result. The method of calibration is realized completely on the basis of the measuring principle of the image probe, without the existence of the errors of calibration principle. The process of calibration is based on the self-calibration principle, a virtual calibration point is formed by fixing a target object and moving the probe, then the calibration operation is fulfilled by constructing a vector, therefore, the operability of equipment is improved; by calculating the position of the image optical centre of an probe image sensor to be taken as the calibration origin, a new measurement error caused by the offset of a coordinate system is avoided to be introduced after the multiplying power of the probe is adjusted, the requirements of measurement in different application situations are ensured, and as the probe self-calibration technology is adopted, the calibration of the probe is ensured to have very high accuracy; the error self-modification is realized by moving a precise three-dimensional moving mechanical device to extract error meshes.

The invention relates to a full optical fiber current transformer. After passing through a Loyt depolarization device, a light beam emitted by a light source enters an integrated optical device and produces two beams of linearly polarized light through the processing of the integrated optical device; and after passing through a polarization maintaining optical fiber delay line and a lambada / 4 wave plate, the two beams of the linearly polarized light are converted into two beams of elliptically polarized light and enter sensitive optical fibers for transmission. Due to the Faraday magnetic optical effect, the two beams of the elliptically polarized light produce a phase difference under the action of a magnetic field produced by a tested current; subsequently the two beams of the light enter the sensitive optical fibers again after being reflected by a reflector; and the two beams of the light interchange the light paths and produce the phase difference again under the action of the magnetic field produced by the tested current. The two beams of the elliptically polarized light carrying current information return to the integrated optical device via the lambada / 4 wave plate and the polarization maintaining optical fiber delay line to form interference light which is sent to a photo detector. The photo detector converts a light intensity signal carrying the information of the tested current into a voltage signal which is sent to a double closed loop control device. The double closed loop control device respectively completes the phase zero setting closed loop control and the modulated wave resetting closed loop control of the two beams of the linearly polarized light according to the voltage signal.

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 discloses a timber optimized truncate method and relative optimized truncate saw. First, inputting the saw data list which comprises target saw length and quality parameters into the computer; when the sawed timber that longitudinally supplied passes the position relative to the detecting device, the detecting device reads the information of sawed timber into the computer, and the computer according to the input saw data list and said information to select the optimized sawing method; the saw machine according to said method processes truncating on the timber. Two sides of said truncate machine individually have a feeding platform and a finished product classifying platform; wherein, said feeding platform has a detecting device; said finished product classifying platform has a finished product classifying device; and a waste removing device is arranged between them.

An electronic hand tool type caliper includes a scale track located along a scale member reference edge that forms a sliding bearing with a mating surface of the caliper slide, thereby maintaining proper alignment of the slide jaw. Placing the scale track along the reference edge is advantageous in that the reference edge surface is inherently precisely machined and particles are excluded by the inherently close fit and the wiping action of the sliding bearing. A readhead sensor is mounted within the slide surface that mates to the reference edge to provide the sliding bearing. Thus, a very small readhead sensor may be reliably positioned at an extremely small gap relative to the scale in a protected operating environment, without detrimentally affecting cost, slider friction, or signal strength. High resolution digital signals may be provided.

The invention relates to a measuring device and a measuring method for the diffraction efficiency of a grating. The device comprises a monochromatic source, a beam splitter, a grating rotary table, detectors, a two-dimensional translation platform and a computer. The method is characterized in that: the second detector and the third detector are adopted to move on a small arc and a big arc respectively to detect the energy of a diffracted beam L3 of the grating to be tested; and the method realizes the aims of diminishing a measurement blind zone and reducing the requirement on the size of an optical platform. The double light path synchronous measurement is adopted to remove measurement errors caused by the instability of the light source.

The invention discloses a MEMS gyroscope difference measurement way. Two MEMS gyroscopes which are quite similar in environment sensitivity are selected out to form a gyroscope difference pair and angular velocity sensitive shafts of two MEMS gyroscopes are in opposite direction by installation, in parallel with a same tested drive shaft, and are sensitive to a same outside input angular velocity. Main parameters of two gyroscopes and an environmental coefficient ratio are determined through a test and a nominal test. When in practical application, the input angular velocity value of high precision is resolved according to an input angular velocity real-time solution formula. The invention selects out the gyroscopes of the same type and the same processing art, uses the similarity of response property to environment factors of the MEMS gyroscopes of the same models and property of suppression of output drift by difference installation and improves measuring precision of the MEMS gyroscopes through processing output data of the gyroscopes. The invention is suitable for application areas of various MEMS gyroscopes, in particular for situations of low requirement on production cost of the MEMS gyroscope and high precision of system output.

A special tape (22) for measuring blocks used in the construction of wood structures includes two special scales. A first scale has marks (32) spaced at 14½ inch intervals for making blocks for studs, and a second scale has marks (34) spaced at 22½ inch intervals for making blocks for rafters. The tape (22) is longitudinally placed along a two-by board (500) and marks (36) made on the two-by board (500) at the desired intervals of 14½ or 22½ inches. The two-by board (500) is then cut at the marks (36) to create the blocks, which are then placed between the studs or rafters.