Method for remotely determining vibration amplitude

FIELD: measuring equipment.

SUBSTANCE: by means of a coherent radar unit or a coherent sonar, operating in the ultrasonic range, a vibrating surface is irradiated. The reflected signal is received, and the vibration frequency is measured. The amplitudes of the first four harmonics are measured, and the values obtained are evaluated. Based on the results of this evaluation, a pair of harmonics - either odd or even - is selected, and the ratio of the amplitudes of these harmonics is determined. From this amplitude ratio, the vibration amplitude value is calculated.

EFFECT: increasing the accuracy of determining the vibration amplitude and expanding the method application scope due to eliminating the effect on the results of the measurements of the phase shift factor of the signal.

1 dwg

 



 

Same patents:

Phase reading // 2556748

FIELD: measurement equipment.

SUBSTANCE: invention relates to metrology, in particular to phase meters for determination of acoustic or vibration disturbances. The method of distributed acoustic reading provides the measurement of derivative or rate of change of the signal scattered in the opposite direction in fiber. The method is implemented by sending of an input signal into a section of optical fiber, reception of the returned signal scattered in the opposite direction from the named optical fiber in response to the named input signal, comparison of the first returned signal scattered in the opposite direction from the section of the named fiber at the first moment of time, and the second returned signal scattered in the opposite direction from the same part of the named fiber in the second another moment of time. The first returned signal is modulated by the first frequency shift, and the named returned second signal is modulated by the second frequency shift. Then the rate of change of the phase in time for the named signal scattered in the opposite direction is calculated. The device contains an optical fiber, the receiver of the signal scattered in the opposite direction, the output interferometer containing the frequency modulator, the phase detector.

EFFECT: improvement of quality of phase component reading.

17 cl, 4 dwg

FIELD: measuring instrumentation.

SUBSTANCE: mechanical wave converter includes lighting, water tank with mirror unit, and stand supporting photosensitive element. Lighting is installed on damper at an angle towards vertical. Beams of lighting fall onto mirror unit in the water tank and reflect from it to photosensitive element mounted on Textolite stand. Sensitive area size in the photosensitive element is selected equal to the size of light spot of reflected light.

EFFECT: enhanced sensitivity and reliability of device.

1 dwg

FIELD: measurement equipment.

SUBSTANCE: group of inventions relates to measurement equipment. The device to monitor vibroacoustic characteristic of a lengthy object according to the first version of realisation comprises a transmitter of optical radiation, two receivers, two sensitive elements, made in the form of optic fibre, two splitters, three communication channels, two couplers, three amplifiers. Fibres are channels of communication of a fibre optic transmission line, the length of which is not less than half of length of the sensitive element. At the same time the outlet of the transmitter is connected only by one first communication channel to each of inputs of two splitters, each of which is accordingly connected to one of sensitive elements, the outlet of one of splitters is accordingly connected by means of the second communication channel of the fibre optic transmission line to the inlet of one receiver of optical radiation, and the outlet of the other splitter by means of the third communication channel - to the inlet of the other receiver of optical radiation. According to the second version of realisation, the outlet of the transmitter is connected only by one first communication channel of the fibre optic transmission line to the input of the first splitter, which is connected to one end of the first sensitive element, which by the opposite end is connected to the inlet of the second splitter connected to the second sensitive element, the outlet of one of splitters is accordingly connected by means of the second communication channel of the fibre optic transmission line to the inlet of one receiver of optical radiation, and the outlet of the other splitter by means of the third communication channel - to the inlet of the other receiver of optical radiation.

EFFECT: increased accuracy of measurements.

7 cl, 3 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment, namely to optical methods of measurement of object vibration parameters. A video image signal of the investigated object is generated with the help of a video camera, then they digitise the specified signal with the help of an analogue-digital converter, the digitised video image is processed with the help of a PC, information is produced on absolute parameters of vibration of the points of the investigated object on a video image.

EFFECT: increased efficiency of vibration diagnostics, expanded area of its application and increased accuracy of vibration parameters measurement.

3 cl, 1 dwg

FIELD: measurement equipment.

SUBSTANCE: position indicator of an absorbing rod in a reactor core of RNMK-1000 type comprises a servodrive, which includes the following serially connected components: a DC motor, a step-down reducer with an electromagnetic coupling of moderating vibration, an electromagnetic coupling of rod stopping, a transport drum with a metal tape, at the end of which there is an absorbing rod fixed, a reducer with a non-linear gear ratio and a selsyn sensor. At the same time the selsyn sensor via a cable route is connected in series with a unit of resistive dividers of phase voltages, closing the phase windings of selsyn sensor rotor synchronisation, a computing complex and an address decoder converting phase voltages of selsyn sensor synchronisation windings into a digital code, which characterizes address and position of the absorbing rod in the reactor core. This information is transmitted to a mnemonic table of the rod position indicator, and via an additional slot through the RS-485 interface arrives to a local information network of a power unit.

EFFECT: increased reliability, accuracy of registration of rod position, increased legibility of measurement results display and reduced power intensity.

4 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment. Investigated object is covered with reflective marks of round shape as a test-object. Binary images of this marks and traces of their vibrational blurring are formed. In the absence of vibrations, determined are coordinates of centre of gravity of each mark, and its radius. In the presence of vibration, additional matrix is formed, each fragment of which is a corresponding vibrational blurring trace of mark turned to 90° relative to the mark centre of gravity. For each mark formed are two areas of non-intersection, each of them is an area of connected elements related to vibrational blurring trace of mark, but not related to additional matrix fragment corresponding to it. Coordinates of centres of gravity of non-intersection areas of mark are determined. From centre of gravity of each mark through centre of gravity of its one non-intersection area directed is aiming beam of this mark. Coordinates of two characteristic points of a mark are determined. Half-width of mark vibrational blurring trace is determined as the difference between the distance from centre of gravity of this mark to its first characteristic point. Value of projection of a mark vibration displacement amplitude vector is determined as the difference between half-width of vibrational blurring trace of the mark and its radius. Direction of this projection is determined as tilting angle of the mark aiming beam in image plane.

EFFECT: enlarging functional capabilities.

7 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to measurement equipment. Investigated object is covered with reflective marks of round shape. Binary images of marks and traces of their vibrational blurring are formed. In the absence of vibrations, determined are coordinates of centre of gravity of each mark, its square and radius by square. Two additional matrixes are formed. Each matrix consists of fragments. Centre of gravity coordinates of each fragment are aligned with centre of gravity coordinates of corresponding mark. For each mark, formed are intersection areas, calculated are total quantity of intersection areas of a mark and quantity of intersection areas of a mark, which centres of gravity coincide with the mark centre of gravity, determined are coordinates of centres of gravity of intersection areas of a mark, which do not coincide with the mark centre of gravity, and among them found is the centre of gravity, distance from which to the mark centre of brevity is maximum, it is recorded as the centre of gravity of the most remote from the mark and its intersection areas. Half-width of mark vibrational blurring trace is determined as product of marks intersection areas quantities, which centres of gravity coincide with the mark centre of gravity, and ring width. Direction of projection of a mark vibration displacement amplitude vector is determined as intercept tilting angle connecting the mark centre of gravity with the centre of gravity of the most remote from it intersection area of the mark. Value of this projection is determined as the difference between length of this intercept and half-width of mark vibrational blurring trace.

EFFECT: enlarging functional capabilities.

4 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to distributed measurements, and namely to distributed sensors of acoustic and vibration actions. In a distributed sensor of acoustic and vibration actions, which includes a sensitive element in the form of a fibre-optic cable and a coherent phase-sensitive optic reflectometer optically connected to it through an optic interface and containing a source of periodic sequence of optic pulses and a receiver of scattered radiation with a photodetector, which are optically connected to the interface, which is intended to convert scattered optic radiation to an electric signal supplied to a processing unit, with that, a source of periodic sequence of optic pulses and the processing unit are electrically connected to a control and synchronisation unit, and the source of periodic sequence of optic pulses and/or the receiver of scattered radiation is of a multichannel type and has the number of channels of at least two and is provided with a possibility of recording reflectograms formed in each of the channels, the receiver of scattered radiation includes a Mach-Zehnder or Michelson nonequiarm interferometer with faraday mirrors; with that, the interferometer has at least two output channels, each of which is connected to the photodetector, and the control and synchronisation unit has the possibility of providing separation and independent processing of signals from each of the output channels of the interferometer.

EFFECT: increasing guaranteed sensitivity and range of action of a distributed sensor of acoustic and vibration actions.

5 cl, 7 dwg

FIELD: physics.

SUBSTANCE: apparatus for monitoring vibroacoustic characteristics of an extended object comprises a continuous semiconductor laser, an optical modulator designed to generate a periodic sequence of rectangular pulses with duration in the range of 50-500 ns and repetition frequency of 0.2-50 kHz, a sensitive element in form of a fibre-optic cable, a unit for inputting optical radiation into the sensitive element and outputting scattered radiation, a photodetector designed to convert scattered optical radiation into an electrical signal, and a signal processing unit with a processor, wherein the continuous semiconductor laser is equipped with a Bragg selective reflector capable of reducing the bandwidth of the continuous radiation of the laser to less than 100 kHz, and the optical modulator is in form of an acoustooptical modulator on a travelling acoustic wave, configured to generate a periodic sequence of rectangular pulses with extinction coefficient K≥10CHlg(TCHf), where T is pulse duration and f is repetition frequency.

EFFECT: longer range, higher sensitivity and resolution of the apparatus.

9 cl, 5 dwg

FIELD: engines and pumps.

SUBSTANCE: proposed system comprises light source to transmit light onto shaft surface via multiple optic fibres made at multiple points nearby said surface in, in fact, axial direction between the ends of at least one shaft, high-temperature reflection probe built around fibre bundle to detect light reflected from shaft surface and mechanism to measure torque or oscillation at the shaft. The latter comprise coding mechanism composed of changed texture shaped to wedge-like groove on shaft surface of variable depth. Said depth generates the front and rear working point signals so that appropriate time delay can be detected from whatever two positions of said groove for determination of shaft twist angle by differentiation of reflection pattern characteristics during every rotation cycle.

EFFECT: higher precision of measurements.

23 cl, 24 dwg

FIELD: instrument engineering.

SUBSTANCE: converter can be used for measuring parameters of acoustic fields in gases and liquids. Fiber-optic converter has optical radiation source exciting circuit, optical radiation source, optical coupler, auxiliary optical radiation, fiber-optic light guide made in form of cylindrical two-channel coaxial tied structure, which has rod single-mode waveguide and tubular single-mode waveguide. Device also has optical radiation divider, which divides optical radiation from rod waveguide and tubular waveguide, optical radiation receiver for receiving optical radiation from output of rod waveguide , additional optical radiation receiver which receives optical radiation from output of tubular waveguide, and analog signal processing unit.

EFFECT: improved precision of fiber-optic converter.

3 dwg

FIELD: the proposed mode and the arrangement are designed for definition of the forms of surface vibrations.

SUBSTANCE: the arrangement for definition of the forms of surface vibrations has a source of light, an investigated surface with an indicator, a recorder, a source of vibrations. Such arrangement has a matrix of photoreceivers, a matrix of electronic keys, an analogue-digital transformer, a block of controlling the keys. At that the beam of light reflected from the investigated surface is optically connected with the matrix of the photoreceivers which outputs are successively connected through the first inputs of the matrix of the electronic keys , the analogue-digital transformer is connected with the input of the recorder and the outputs of the block of controlling are connected with the second matrixes of the electronic keys. At that the source of vibrations has a kinematics connection with the investigated surface.

EFFECT: expands the field of application.

3 cl, 2 dwg

FIELD: survey of boreholes or wells.

SUBSTANCE: device comprises laser, input unit to input optical radiation in sensing member; wavelength-division multiplex unit, filter, optical isolator, optical modulator and outlet directed beam splitter. Laser is connected with wavelength-division multiplex unit. Outlet directed beam splitter is connected to the input device. Optical isolator and outlet directed fiber-optic beam splitter are linked to optical modulator and constitute united loop, which forms continuously operated narrow-band laser. The continuously operated narrow-band laser is connected with wavelength-division multiplex unit. Outlet directed beam splitter is connected to the input unit. Photodetector is linked to analog-digital converter and with the input unit. The analog-digital converter is connected in series with buffer memory included in signal processing unit linked to processor. Timing means is attached to optical modulator, analog-digital converter and buffer memory.

EFFECT: increased sensitivity and responsiveness, increased operating sensor length and spatial resolution.

4 cl, 1 dwg

FIELD: the invention refers to measuring technique namely to the means of measuring amplitudes of ultrasonic variations.

SUBSTANCE: the oscillating system is installed in such a manner that its acoustic axle is transversely to the optical axle of light sources forming impulse light radiation of various lengths (colors) into a cylindrical beam. Duration of impulses is set as equal to thousandth of the period of working variations of the oscillating system. The frequency of impulse sequence is set so that moments of forming impulses of light radiation of waves (colors) of one and the same length coincides with the moment of maximum displacement in other direction. The amplitude of vibrations is defined according to relative displacement of images of radiating surface in the moments of forming impulses of light radiation of different lengths of waves(colors)carrying out visual observation through a microscope provided with an ocular scale or a net.

EFFECT: increases accuracy and speed of fulfillment of measuring without preliminary calibration.

6 dwg

FIELD: measuring technique.

SUBSTANCE: method comprises illuminating the vibrating body with light beam generated by means of two pulse radiation sources of different wavelength so that the vibrating body overlaps a part of the light beam. The moment of pulse generation of the first source is synchronized with the maximum deviation of the edge of the vibrating body in one direction. The moment of pulse generation of the second generator is synchronized with the moment of maximum deviation of the vibrating body to the opposite direction. The light beam passes through the diaphragm. The remaining part of the light beam is split into two equal beams. Each of the beams is incident on an individual converter of illumination intensity to voltage. The amplitude of vibration is judged by the difference between the voltages recorded.

EFFECT: enhanced accuracy of measurements.

4 dwg

Laser hydrophone // 2295116

FIELD: hydro acoustics.

SUBSTANCE: laser hydrophone can be used for measuring parameters of noise radiation of moving underwater object. Optical grating is projected into tested medium by means of optical system; pitch of grooves of grating is known, which grooves belong to plane which has image to be oriented orthogonal in liquid and images of the grooves themselves are parallel to casing of underwater object's case. Oscillation velocity of sonic wave, irradiated by case of underwater object's case can be found from frequency of optical signal induced by motion of light-dissipating particles. There is ability of changing in length of measuring base and of conducting measurements of oscillation velocity of sonic waves as "in site" and inside larger tested area. When laser hydrophone operates in particular mode there comes the ability of measuring of distribution of oscillation velocity value along casing of underwater object's case. Local characteristics and integral characteristics of acoustic field can be measured simultaneously in tested area along longitudinal axis of underwater object.

EFFECT: improved precision of measurement.

4 cl, 1 dwg

FIELD: the invention refers to the field of control-measuring technique and may be used for definition of the amplitude of vibration of objects in tens of nanometers on the spectrum of an autodyne signal.

SUBSTANCE: the mode of definition of the amplitudes of vibrations includes irradiation of an object with laser emanation, transformation of radiation reflected from it into an electric signal, decomposition of the signal into a spectral row, measuring of the amplitude of chosen harmonies. At that the reflected signal is transformed into an autodyne signal providing feedback optical liaison by way of direction of the reflected beam into the resonator of a laser diode, in the spectral row two neighboring harmonies are chosen, the amplitude of vibration is defined out of the given mathematical correlation.

EFFECT: expands diapason of the measured amplitudes of vibrations and possibility of carrying out absolute measurements.

3 dwg

FIELD: measuring technique.

SUBSTANCE: method comprises automatic detecting the dangerous vibration and time of stay of personal in the zone of dangerous vibration from the analysis of current values of frequency and level of vibration. The device comprises vibration transducer (1), unit (2) for processing electric signals, computer (15), indicator (16) of dangerous level of vibration, and indicator (17) of permissible time period for stay of personal in the zone of dangerous vibration.

EFFECT: expanded functional capabilities.

5 dwg

FIELD: measuring technique.

SUBSTANCE: ultrasonic indicator comprises front panel, transparent electrode, and layer of colloidal suspension of particles in a dielectric liquid interposed between the electrodes. The complex refraction index of colloidal particles differs from that of the dielectric liquid. The second electrode is made of a piezoelectric plastics provided with the conducting coating whose outer side is connected with the transparent electrode.

EFFECT: expanded functional capabilities.

1 dwg

FIELD: physics, instruments.

SUBSTANCE: invention may be used for remote contactless vibration diagnostics of machines, mechanisms, and building structures and facilities. The second TV camera with a photosensitive CCD matrix positioned in the focal plane of the second TV camera lens, a double-channel PC interface device, and a PC are introduced in the laser meter of the angular and linear vibration displacement amplitude, which includes laser, a semi-transparent mirror installed at 45°, and TV camera with a photosensitive CCD matrix positioned in sequence along the optical axis. The laser beam after reflecting from the semi-transparent mirror and the optical axis of the second TV camera lens are normal to the vibrating surface. The optical axis of the first TV camera with a photosensitive CCD matrix, which is installed at such a distance from the lens as to form a sharp image of the laser spot, is positioned at an angle to the optical axis of the laser beam striking the vibrating surface. Both TV camera outputs are connected to the inputs of the double-channel interface device. The output of the device is connected to the PC input. If the diffuse and reflected components in the radiation reflected by the vibrating surface are insufficient for the operation of both TV cameras, a semi-transparent plate with matte and mirror surfaces is attached to the vibrating object. This enhances the efficiency and makes it possible to automate the measurement process due to the use of both diffuse and reflected components of the reflected radiation.

EFFECT: measurement process automation and increased efficiency.

2 cl, 1 dwg

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