572results about How to "Improve measurement stability" patented technology

The invention relates to an apparatus and a method for a scanning probe microscope, comprising a measuring assembly which includes a lateral shifting unit to displace a probe in a plane, a vertical shifting unit to displace the probe in a direction perpendicular to the plane, and a specimen support to receive a specimen. A condenser light path is formed through the measuring assembly so that the specimen support is located in the area of an end of the condenser light path.

The invention discloses a dual-polarization interferometric fiber-optic gyro which belongs to the field of communication technology. The fiber-optic gyro comprises a light source, two linear polarized light generating circuits, two signal detection light paths, a polarized beam splitter/combiner, a polarization-maintaining coupler, a phase modulator and a polarization-maintaining fiber-optic ring; wherein the light source is connected with the input ends of the two linear polarized light generating circuits by optic fibers; two output ends of the two linear polarized light generating circuits are respectively connected with two ports at the same side of the polarized beam splitter/combiner by optic fibers through one signal detection light path; the port at the other side of the polarized beam splitter/combiner is connected with the polarization-maintaining fiber-optic ring through the polarization-maintaining coupler; and the phase modulator is connected between the polarization-maintaining fiber-optic ring and the polarization-maintaining coupler by optic fibers. Compared with the prior art, the fiber-optic utilizes the dual-polarized light to carry out the detection, thereby greatly improving the measuring precision and the measuring stability of the rotating angular velocity; meanwhile, the fiber-optic gyro has the advantages of simple structure, low cost, small volume, high sensitivity and wide application range simultaneously.

The invention discloses a blade state monitoring device and a monitoring method of a wind turbine generator system. The blade state monitoring device comprises a sensor and a controller, wherein the sensor is arranged on a tower rack, a cabin or a generator of a wind turbine generator system with blades, and is used for monitoring the distance between the sensor and a sucking surface of a blade, and used for acquiring actual distance data between the sucking surface of the blade and the sensor; the controller is connected with the sensor so as to receive the actual distance data output from the sensor, and is used for judging the torsion state of the blade according to initial distance data and the actual distance data between the sucking surface of the blade and the sensor. According to the blade state monitoring device, as the distance between the sensor and the blade is monitored through an external sensor, and whether the torsion deformation of the blade is too large or not is judged according to the acquired actual distance data and the initial distance data, whether the blade has the risk of cracking or structural abnormity or not can be judged, corresponding measures such as repairing can be taken in time, the loss caused by blade cracking can be reduced, and meanwhile the cost of blade component replacement can be reduced.

The invention relates to a rapid width measurement system for tobacco shreds, which is mainly composed of an image filtering and region segmentation unit, a subimage contour extraction unit and a single tobacco shred width calculation unit. By using the advanced computer technology, image recognition technology and real-time digital image processing technology, the invention can realize the rapidand accurate width measurement of a large number of tobacco shreds. By using the invention, multiple tobacco shreds can be measured in one step, and the average width and variability of each tobacco shred can be rapidly and accurately calculated. The invention has the characteristics of simplified equipment structure, accurate width measurement of tobacco shreds and high measurement efficiency.

The invention discloses a moving object posture measurement method based on prior knowledge model optimization, belongs to the technical field of computer vision measurement, and relates to a method for measuring moving object posture through the combination of a binocular vision principle and prior knowledge model posture optimization. The measurement method comprises the following steps: firstly establishing an offline prior model of a detected object, acquiring a movement image of the detected object in real time through a binocular camera, and extracting, matching and reconstructing the image features to obtain a three-dimensional coordinate of a mark point; optimizing mark point position information in posture measurement through the adoption of the prior distance relation between the mark points, thus improving the spatial position precision of the mark points, and finally achieving the high-precise posture measurement. The moving object posture measurement result is optimized through the prior model constraint, and the measurement precision and the stability of a posture measurement system under a complex environment are improved; a combined mark point is used as the image feature, the measurement precision is high, and the applicable range is wide.

The invention relates to a two-slit interference fringe decoding spectrum confocal displacement sensor and a displacement measurement method thereof. A grating spectrometer is used in a spectrum analyzing unit of a current spectrum confocal displacement sensor, the beam split principle is complex, cost is high, detected wavelength can drift along with time and environment, and the measuring accuracy of the sensor is affected. The sensor comprises a broadband point light source, a non-aberration spectroscope, a dispersing lens group, a confocal pinhole, a non-aberration collimating lens, an interference two-slit screen, an adaptive lens, a rectangular diaphragm and a linear array CCD. Reflected light of the surface of a measured object is subjected to filtering through the confocal pinhole, then quasi-monochromatic light is formed, after non-aberration collimating, the quasi-monochromatic light is divided into two sub column face light sources by two slits, interference is formed, the widths of the interference fringes and the wavelength of the reflected light of the surface of the measured object are in good linear relation, and by interpreting the widths of the interference fringes, measuring of object displacement is achieved. The displacement sensor and the method have the advantages of being low in cost, good in linearity and high in resolution ratio, and meanwhile an instrument is simple in structure and easy to machine.

The invention relates to a light curtain-based vehicle size automatic measuring system and a measuring method thereof. The system consists of a measuring host, a signal acquisition device and a light curtain sensor array which are connected, wherein the light curtain sensor array is a three-dimensional structure which consists of a height measuring light curtain sensor, a width measuring light curtain sensor and a length measuring light curtain sensor; output ends of the height measuring light curtain sensor, the width measuring light curtain sensor and the length measuring light curtain sensor are connected with the signal acquisition device; and after a detection signal transmitted by the light curtain sensor array is received by the measuring host, the height, the width and the length of a vehicle to be measured are calculated by the measuring host. The system is rational in design; an accurate measuring function of the vehicle size is realized; the problem of error in image contour dimension caused by the fact that a camera screenshot is not in the same plane as a land mark and a vertical mark existing in a camera image photograph measuring method is solved; the measuring accuracy and stability are improved; and all the degree of difficulty for handling, the anti-interference capacity and the maintainability are dramatically improved.

Provided is a gas flux measuring device measuring a region, such as forest, as a measuring object with no influence by concomitants and with high responsibility and excellent measuring stability. The device comprises a laser beam source, laser output controller, wavelength modulation controller, first light receiver, first direct current component detector, first wavelength modulation demodulator, optical system, reference cell, second light receiver, second direct current component detector, second wavelength modulation demodulator, third wavelength modulation demodulator, analyzer, adder, temperature measuring means and pressure measuring means. The device further comprises a flow velocity measuring means directly measuring horizontal 2-directional flow velocity components and a vertical directional flow velocity component of a gas flow in the measuring region and putting out these measurement signals into the analyzer. Based on the signals inputted from the flow velocity measuring means, the analyzer makes analysis based on the eddy correlation method and obtains, by calculation using this analysis result, a momentum flux and concentration of the measuring object gas.

The invention provides a method for measuring temperature in real time. The method is characterized in that temperaturemeasurement comprises the following steps: processing radiation lights emitted by a measured object by a light-splitting mechanism to obtain two or more than two multi-wavelength radiation light beams; receiving radiation energies with different wavelength by a photoelectric detector to obtain a radiation energy ratio; calculating corresponding temperature values according to a formula of the blackbody radiation theory; obtaining correction factors of single-wavelength radiation energies by taking a temperature value calibrated by a standard blackbody radiation source in a high-temperature range as a criterion; and calculating the corrected single-wavelength radiation energies to obtain a temperature value in a low-temperature range. The method has the advantages that with the adoption of a multi-wavelength optical temperature measuring technology, measurement errors caused by emissivity of an object surface, a temperature measuring distance, a temperature measuring angle, and environmental factors such as air flows, impurities and the like are reduced, and the temperature measuring accuracy is improved; the measuring accuracy and stability is improved, and the measuring range is widened extremely by the corrected single-wavelength radiation temperature measurement.

The present invention relates to safety monitoring system, and is flexibility monitoring method for large span bridge structure. Whole bridge pressure field is first established with water tanks set in the unchanged location, water pipes set horizontally and city water supply system to lead water pressure to deformation location of the bridge; and the pressure transducer is fixed to the measured part. The pressure change is converted into flexibility change and monitored with the computerized monitoring system, which consists of water tank, water pipes, pressure transducer, A/D converter, computer, etc. The present invention has high measurement stability, great measurement range, low measurement cost and high practical value.

The invention belongs to the technical field of sensors, and discloses a nonlinear compensating circuit of a resistance bridge type sensor. The nonlinear compensating circuit comprises the resistance bridge type sensor, an excitation voltage source and a signal amplification circuit; a common mode resistor is connected between the resistance bridge type sensor and the negative end of a bridge power supply source in series; the output end of the signal amplification circuit is connected with the common mode resistor in series through a feedback resistor. The nonlinear compensating circuit has the advantages that signals (voltage) obtained after outside information sensed by the resistance bridge type sensor is converted are/is amplified through the signal amplification circuit, after pressure parting is carried out on the resistance bridge type sensor and the common mode resistor with the appropriate proportion (by changing the feedback resistor), and nonlinear compensating for the resistance bridge output type sensor with the gradually-increased output signal sensitivity is accordingly achieved. In addition, the signal amplification circuit in a circuit can be a digital programmable amplifier, the digital debugging zero position and the full scale can be applied, and the problems of low accuracy and poor stability caused by resistor replacement in the debugging process are solved. The measurement accuracy and the stability of the sensor are improved.

The invention relates to high speed parallel multichannel data system for nucleus spectrum and nuclear electronics. It is made up of 4 independent channels, and includes analog circuit, 14 bits ADC, and a 4 channel timer distributor. The analog signal would be transformed to digital quantity and input into large capacity FPGA chip to take online analysis of time, amplitude, sampling points information and relativity, taking effective data selection and inputting into host computer through network or USB2.0 interface.

The invention discloses a low-noise dual-polarization interference optic fiber gyroscope belonging to the technical field of communication. The optic fiber gyroscope comprises a light source, two linear polarized light generating circuits, two circulators, a polarizing beam splitter/combiner, a 3 multiplied by 3 polarization-preserving coupler, two photoelectric detectors, a phase modulator and apolarization-preserving optical fiber ring, wherein the light source is connected with input ends of the two linear polarized light generating circuits through optical fiber; two output ends of the two linear polarized light generating circuits are respectively connected with the optical fiber of two ports at one side of the polarizing beam splitter/combiner through the circulator; the port at theother side of the polarizing beam splitter/combiner is connected with the polarization-preserving optical fiber ring through the 3 multiplied by 3 polarization-preserving coupler; and the polarization-preserving optical fiber ring and the polarization-preserving coupler are connected with the phase modulator through optical fiber. Compared with the prior art, the optic fiber gyroscope realizes the inhibition of noise sensitivity by using the symmetry of the 3 multiplied by 3 polarization-preserving coupler and meanwhile is characterized by simple structure, low cost, small volume, high sensitivity and wide application range.

The invention relates to the technical field of coke oven baking process, disclosing an automatic detection and analysis system for temperatures at multiple points of coke oven baking. The automatic detection and analysis system comprises a thermoelectric couple, a compensation lead, a lower computer, a switch board and an upper computer, wherein the upper computer comprises an upper computer work station and a redundancy upper computer work station which are respectively connected with the switch board and respectively comprise a database, a real-time data acquisition module, a data conversion module and a data integrated processing module. According to the automatic detection and analysis system disclosed by the invention, the stability and the data analysis capability of the temperature detection and analysis system in the coke oven baking process can be improved; the process maintenance load, the management cost and the fault rate of equipment are reduced; the coke oven baking quality is improved; the function of full-automatic detection and analysis of temperatures at the multiple points of the coke oven baking is achieved; the actual temperature of a furnace body is ensured to be basically matched with a planned temperature curve; the daily expansion ratio of a coke oven building body is controlled within normal range; the smooth implementation of a coke oven process is ensured; and the quality of the coke oven body is improved.

The invention belongs to the technical field of computer vision measurement and relates to a method for three-dimensional data registration based on flexible feature points. According to the method, a ladder type measurement system is adopted for three-dimensional data measurement of a large part having a free-form surface; by utilization of control point information in public view field areas of a global control system and a local measurement system, control points are matched, and a transfer matrix is obtained; by utilization of the transfer matrix, three-dimensional point cloud data measured by the local measurement system is unified into the global control system, finally three-dimensional reconstruction is performed on data of the global control system, to achieve three-dimensional data registration of the large part. According to the method, by utilization of the projection flexible control points, the problems of complex control point layout and measurement blind areas in the process of measuring a conventional large part are solved, the measurement positioning is adjusted in real time according to surface features of the measured part, and site adaptability of the measurement system and data registration precision and measurement stability are improved.

The invention discloses an improved wind load pressure sensor, comprising a sensor shell, an oil charge sensitive body and a signal conditioning circuit, wherein, the oil charge sensitive body is composed of a sensitivity body shell in the form of a groove, a silicon integrated sensitive chip and an elastic separation film fixed on the opening of the groove, the ring circumambience of the back pressure face of the silicon integrated sensitive chip is fixed at the bottom of the groove through a fixed supporting ring in a sealing manner, the back pressure face of the silicon integrated sensitive chip is communicated with ambient pressure through a back pressure airway tube, the pressure surface of the silicon integrated sensitive chip is provided with a Wheatstone bridge on which a strain resistor is led to the signal conditioning circuit through an internal lead and a lead column and then is output, the non-pressure surface of the silicon integrated sensitive chip is provided with a temperature sensor, a heating resistor and a constant temperature control circuit controlling the heating resistor according to the temperature sensor, and silicon oil is filled among the elastic separation film, a groove internal ring surface and the pressure surface of the silicon integrated sensitive chip. The invention can control the temperature of the oil charge sensitive body, and eliminate the problem that an oil charge micro-pressure sensor is in fault due to the influence of ambient temperature, thereby realizing high-accuracy survey of wind loads.

The invention discloses a reference waveform determination method realized by gas ultrasonic flow meter based on a cross-correlation time-difference method. The measurement principle of the gas ultrasonic flow meter based on the cross-correlation time-difference method is that a signal propagation time difference of two signals is acquired through calculation of a cross-correlation function of ultrasonic receiving signals when gas in a pipeline is in a static state and a flowing state, and then the flow velocity of the gas is determined. When flow measurement is performed, the ultrasonic receiving signals at the same flow velocity have certain randomness due to existence of influence factors such as circuit noise, thermal motion of gas molecules, inconsistency of direct and inverse piezoelectric effects of an ultrasonic transducer and the like. Because of importance of reference waveforms in the aspect of calculation of transit time with a cross-correlation algorithm, the invention provides the reference waveform determination method. According to the method, multiple static waveforms are adopted and averaged, and obtained average waveforms are processed and taken as the reference waveforms. The problem about reference waveform selection when the transit time is calculated with the cross-correlation algorithm is effectively solved, and the measurement precision and repeatability of the transit time are improved.

The invention discloses a double polarized light polarization-preserving fiber polarization eliminator, and belongs to the technical field of communication. The polarization eliminator comprises three sections of polarization-preserving fibers with lengths of l1,l2 and l3 respectively, the polarization-preserving fibers with lengths of l1,l2 and l3 are melted and butted in turn, and the double refraction main axis of the polarization-preserving fiber of the rear section and the double refraction main axis of the polarization-preserving fiber of the adjacent front section form an included angle of 45 degrees along the same direction in turn, wherein l3 is equal to 4l1, l2 is equal to 2l1, delta nbl1 is more than or equal to Ldc, the delta nb is the difference of the refractive indexes of the two main axes of the polarization-preserving fibers, and the Ldc is the decoherence length of a light source. Compared with the prior art, the polarized light obtained by the polarization eliminator is closer to natural light, and the polarization eliminating result is more ideal; and the polarization eliminator has simple structure, clear principle and wide application range.