176 results about "In situ calibration" patented technology

A phased array antenna system includes an RF front end, a radome, and an optical calibrator embedded in the radome for enabling in-situ calibration of the RF front end. The optical calibrator employs an optical timing signal generator (OTSG), a Variable Optical Amplitude and Delay Generator array (VOADGA) for receiving the modulated optical output signal and generating a plurality of VOADGA timing signals, and an optical timing signal distributor (OTSD). The in-situ optical calibrator allows for reduced calibration time and makes it feasible to perform calibration whenever necessary.

An encoder calculates position error values and applies compensation values to encoder position measurements in-situ. The encoder includes a scale and a multi-section detector for detecting a spatially periodic pattern, such as an optical interference pattern, produced by the scale. The detector includes spatially separated first and second sections. A signal processor estimates respective phase values from detector sections and calculates a phase difference reflecting a spatial position error in the scale. A compensation value is calculated from the phase difference and included in the estimate of the scale position to compensate for this spatial position error. The compensation values may be calculated and used on the fly, or calculated and saved during an in-situ calibration operation and then utilized during normal operation to compensate uncorrected measurements.

The invention discloses a thrust rack in-situ calibration system, which comprises a standard sensor assembly, a hydraulic system and a loading and unloading control system, wherein the standard sensor assembly comprises a sensor pull rod, a front universal flexible element, a standard sensor and a back universal flexible element, the hydraulic system comprises a hydraulic cylinder, a press cavity oil filling valve, a hand lifting pump, a pulling cavity oil filling valve, an electric joint pressure meter and a pressure cavity energy accumulator, the loading and unloading control system comprises a self control pump, a wide frequency servo motor, a pulse automatic tracking system, a computer and a collecting card, the in-situ thrust calibration system controls the work of the self control pump through the pulse automatic tracking system and the wide frequency servo motor, in addition, measurement signals of the standard sensor are fed back to the computer, the computer transmits the pulse signals to the pulse automatic tracking system through software operation, the automatic loading and unloading on the standard sensor by the hydraulic cylinder is realized, in addition, the necessary time can be stabilized, the loading stability can reach 0.004 percent F.S per 30 minutes (or longer time).

In-situ calibration of a resistivity logging tool is accomplished using a variety of methods in which deep measurement signals are calibrated using acquired and simulated measurement signals.

The invention provides a gas analysis device with an in-situ calibration function. The gas analysis device comprises a sampling chamber, an analysis chamber, a gas analyzer and a calibration module, wherein the sampling chamber is connected with a to-be-detected chamber through a first valve and used for leading in sample gas in the to-be-detected chamber; the analysis chamber is connected with the sampling chamber through a second valve, and a vacuum gauge tube is arranged on the analysis chamber and used for monitoring the degree of vacuum of the analysis chamber; the gas analyzer is arranged in the analysis chamber and used for analyzing and testing to-be-analyzed gas; the calibration module is used for providing standard gas for the gas analyzer and quantificationally calibrating the gas analysis device. The invention further provides a gas analysis method. According to the invention, the gas analysis device is periodically calibrated through the calibration module, bakeout degassing is performed through a heater, gas sweeping and protective gas filling are performed through a sweeping and degassing module, a system is enabled to maintain favorable testing background, testing accuracy is guaranteed, gas strength testing at the level of part per billion can be realized, and the gas analysis device is especially suitable for gas analysis and detection in EUV vacuum environment.

By using a scintillation surveymeter with good calibration performance evaluation for a secondary standard radiation field, and a working standard part obtaining an ambient dose equivalent rate, in cooperation with a portable irradiator, and an irradiator lifter, a laser range finder and a laser locator of a relevant radiation source, in-situ calibration is capable of being performed on fixed, or large-scale, or continuous monitoring type radiation monitors to be calibrated stationed in nuclear power plants, nuclear medical departments, and other nuclear facility operating institutions. Moreover, a time-efficient and effective in-situ calibration method is further provided, which can be performed based upon a standard calibration field that is achieved using a portable ¹³⁷Cs radiation source. The in-situ calibration method is capable of saving the trouble of delivering large-scale monitors, or monitors difficult to move, or monitors requiring continuous monitoring to calibration laboratories for scheduled calibration.

The invention discloses an in-situ calibration method for structure parameters of a large-visual-field binocular stereo vision system by small two-dimensional targets, which belongs to the technical fields of optical measurement and mechanical engineering. The calibration method comprises the following steps of: acquiring images of the small two-dimensional calibration targets which are placed in different positions in a measurement scene; respectively computing external parameters, which correspond to the calibration targets placed in the different positions and are opposite to left and right cameras, according to internal parameters, which are calibrated in an off-line manner, of the left and right cameras, and further computing the structure parameters of the stereo vision system; and finally, establishing an objective function to perform nonlinear optimization on the structure parameters of the stereo vision system. The small two-dimensional calibration targets effectively solve the problems of high cost, difficulty in transportation and storage and inconvenience in application and maintenance of large high-precision calibration targets, and can be applicable to the in-situ calibration of the structure parameters of the stereo vision system in a complicated environment.

The invention discloses a thrust measuring device applicable to a small thrust engine. The thrust measuring device comprises a static frame, a movable frame, an in situ calibration device, a force measuring component and a suspension part, wherein the movable frame, the in situ calibration device and the force measuring component are arranged on the static frame, and the suspension part is used for mounting an engine and can adjust the height of the engine. In the thrust measuring device, the suspension part is composed of a suspension block, a lifting bolt, a lifting thread bushing, an elastic element, a tension part and a rigidity tension and compression part or elastic tension and compression part, the engine is mounted by adopting a suspension way, the quantity of test accessories can be reduced, and mass can be reduced, so that inertia force and frictional force of a test device are reduced, and thrust measurement accuracy is improved; a mechanical loading mode is adopted for implementing static calibration, composition of the in situ calibration device is simplified, time of a test preparatory stage is shortened, and economy of the measuring device is improved; and for a specific engine, appropriate parts are selected for being assembled into the suspension part, and universality of a thrust device can be enhanced.

The invention enables platform-independent sonar calibration. The associated systems and methods have application to underwater sonar systems and components, enabling an unprecedented flexibility in use. The systems and methods of the invention allow for efficient field calibration of sonars as configured for operational use, with high accuracy at low-cost. The invention provides in situ calibration capability for both stationary and moving sonar platforms and is suitable for calibration during operations.

A calibration system for a level meter comprising a tank having a sidewall and a bottom defining a tank interior, and a stilling well coupled to said tank, said stilling well having a sidewall, proximal and distal ends and a stilling well interior, and the distal end in fluid communication with the tank interior near the tank bottom, said proximal end of said stilling well being sealingly coupled to said level meter, said stilling well having a calibration fluid path allowing fluids to flow out of said stilling well interior; said stilling well having a vent opening that is sealingly closable near said proximal end; and a source of pressurized gas connectable to said stilling well interior, said stilling well having a measurement configuration where said vent opening is opened allowing said proximal end to vent gases in said stilling well interior, and a calibration configuration, where said pressurized air source is connected to said stilling well and flowing into said stilling well interior, where said pressurized gas may exit said stilling well interior only at said calibration flow path.

The invention relates to a calibration measurement device for steady-state thrust of a 4-25N attitude control engine in a thermal vacuum environment. The calibration measurement device comprises a base transfer frame, shock absorbing blocks, a fixed frame, a balance transfer plate, a single-component balance measurement device, a propellant pipeline, propellant pipeline fixing devices and an in-situ calibration device, wherein the shock absorbing blocks are uniformly mounted between the base transfer frame and the fixed frame; the propellant pipeline fixing devices are fixedly mounted on the periphery of the fixed frame; the propellant pipeline is mounted through the propellant pipeline fixing devices, one end of the propellant pipeline is communicated with an external propellant supply system, and the other end of the propellant pipeline is communicated with a propellant inlet of a to-be-measured attitude control engine; the single-component balance measurement device is mounted at one end of the fixed frame through the balance transfer plate, and the in-situ calibration device is mounted at the other end of the fixed frame. The calibration measurement device meets the requirements of the 4-25N attitude control engine for low thrust calibration measurement and solves the problems that high uncertainty is caused by pipeline constraint, high temperature and vibration in a measurement process, calibration before test run is not proper, the calibration precision is poor and the like.

A method is provided for characterizing spectrometric properties (e.g., peak reflectivity, reflection curve width, and Bragg angle offset) of the Kα emission line reflected narrowly off angle of the direct reflection of a bent crystal and in particular of a spherically bent quartz 200 crystal by analyzing the off-angle x-ray emission from a stronger emission line reflected at angles far from normal incidence. The bent quartz crystal can therefore accurately image argon Kα x-rays at near-normal incidence (Bragg angle of approximately 81 degrees). The method is useful for in-situ calibration of instruments employing the crystal as a grating by first operating the crystal as a high throughput focusing monochromator on the Rowland circle at angles far from normal incidence (Bragg angle approximately 68 degrees) to make a reflection curve with the He-like x-rays such as the He-α emission line observed from a laser-excited plasma.

A method for identifying and quantifying one or more analytes included in a sample comprising a background solvent is disclosed. The present invention enables in-situ calibration and removal of the spectral signature of the background solvent from a composite spectrum so that the spectral features associated with the analyte(s) can be more easily and precisely identified. Further, the method enables estimation of the concentration of the analyte(s) by normalizing the spectrum based on the path length of the infrared radiation through the sample.

The invention discloses an ultralow emission online monitoring system for flue gas pollutants of coal-fired power plants. The system comprises a sampling unit, a back blowing unit, a heat tracing pipe, a calibration unit, a dew-point meter, an air pump, an NOX converter, an analyzing device and a data collecting, processing and transmitting unit. The system is characterized in that an acidification dehumidifier is arranged between the calibration unit and the dew-point meter and used for acidification of flue gas entering the acidification dehumidifier to prevent to-be-tested components in flue gas from dissolving in condensate, and the acidification dehumidifier is provided with an in-situ calibration passage used for calibration of a zero point and a measuring range of the analyzing device. By the ultralow emission online monitoring system, the problem of how to realize accurate and reliable online monitor ultralow emission of sulfur dioxide and nitrogen oxides in desulfurized and denitrified flue gas of the coal-fired power plants is solved, parameters are provided for an ultralow emission process of the coal-fired power plants, and national requirements of ultralow emission online monitoring are met.

The present invention, in one aspect, provides a method for calibrating thermal control elements in situ using a single compound calibrator. In some embodiments, the present invention uses a compound calibrator to calibrate thermal control elements on a microfluidic device. In non-limiting embodiment, the compound calibrator can be a droplet, plug, slug, segment or continuous flow of any appropriate solution that, when heated, yields a thermal response profile with a plurality of features (e.g., maxima, minima, inflection points, linear regions, etc.).

The invention provides an optical trapping based method for in-situ calibration of displacement of a piezoelectric platform. High-precision detection of motion displacement amplitude and frequency of the piezoelectric platform can be realized by analysis of position signals of Brownian motion of standard-size globules trapped in an optical trap system. Besides detection of the piezoelectric platform, standard particles are trapped by laser under microscopic imaging, and position motion signals of the particles are quickly detected by a detector. The piezoelectric platform sends low-frequency fixed-amplitude motion signals to drive a sample chamber to move, the particles trapped in a light trap is subjected to actions of fluid periodic viscous resistance, and voltage proportionality coefficient of a position sensitive detector can be calibrated by detecting the motion signals of the particles. The piezoelectric platform sends signals to drive the sampling chamber to move again, a power spectrum of the trapped particles is analyzed, a peak of the power spectrum is compared with background thermal noise to invert real motion displacement amplitude of the piezoelectric platform, and frequency of the peak stands for motion frequency of the piezoelectric platform.

A simulative load source for in-situ calibration of electric energy meter is composed of zero cross voltage comparator, alamr unit, power supply, single-chip microcomputer, phase-shift current amplifier, current power amplifier and its output circuit, and current protecting circuit.