68results about How to "Increase the measurement range" patented technology

The invention discloses an integrated grating piezoelectric modulation closed-loop high-precision acceleration micro-sensor which comprises a shell. A light source, a grating, a piezoelectric ceramic component and an MEMS (micro-electromechanical system) sensing mechanism are arranged in the shell sequentially along a light path, the MEMS sensing mechanism comprises a mass block and a cantilever beam connected with the mass block, and one surface, facing to the grating, of the mass block is a light reflecting surface. The acceleration micro-sensor is further provided with a photoelectric detector, a signal processing module, a first electromagnetic force generation device, a second electromagnetic force generation device and a current driving module, the photoelectric detector is used for detecting light intensity of interfering beams which are formed by interference of beams reflected by the grating and beams reflected by the light reflecting surface, the signal processing module is used for computing corresponding acceleration signals according of signals of the photoelectric detector, the first electromagnetic force generation device is fixed at the bottom of the mass block, the second electromagnetic force generation device is positioned in the shell and matched with the first electromagnetic force generation device, and the current driving module is used for transmitting current to the first electromagnetic force generation device and the second electromagnetic force generation device, and is connected with the signal processing module.

The invention discloses a laser methane concentration measuring method based on double-spectrum absorption line and waveform matching. A semiconductor laser performs wavelength linear scanning and covering on two specified absorption lines, laser passing through a gas to be measured is subjected to processing such as narrow-band band-pass filtering and high-speed acquisition by a receiving circuit and then subjected to waveform matching with a reference absorption line, various noises and interference removal and an actual absorption line retaining, and finally, real-time inversion of the concentration of the gas to be measured is carried out by adopting a double-spectrum absorption line concentration inversion algorithm. The laser methane concentration measuring method disclosed by the invention solves the contradiction widely existing in the conventional application of a laser absorption spectrum technology in gas concentration measurement that measurement range and minimum detection limit are difficult to consider, expands the concentration measurement range while ensuring the minimum detection limit of laser methane concentration measurement, solves the problem of concentration misinformation of a measuring system caused by optical and electrical interference, and ensures the measurement accuracy.

The invention provides a quartz flexure accelerometer which can improve the measurement precision, is good in sealing performance, and is high in stability. The accelerometer comprises a servo circuit and a meter. The meter comprises an upper torquer, a detection quality assembly, a lower torquer, and a housing. The upper torquer comprises a compensation ring, a magnetic steel, a magnetic pole piece, and an upper yoke. The lower torquer comprises a compensation ring, a magnetic ring, a magnetic pole piece, and a lower yoke. The detection quality assembly comprises a gold-plated film quartz pendulous reed and two torquer coils which are pasted on the quartz pendulous reed.

The application discloses a coupled fiber grating wide-range intelligent high-strength steel wire which is provided with at least one spiral groove. The grooves are internally provided with optical fiber lines and protection layers used for covering the optical fiber lines. Multiple gratings are etched on the optical fiber lines. Meanwhile, the invention also provides a manufacturing method of the coupled fiber grating wide-range intelligent high-strength steel wire. The spiral grooves are arranged on the steel wire, and the size of the spiral angle of the grooves is changed according to strain range of a component so that measurement range of a fiber grating sensor is extended, and adverse factors of limiting measurement range caused by glass fragility of fiber grating material can be avoided; the fiber gratings are arranged in the internal part of the steel wire so that adverse influence on the fiber grating sensor caused by construction factors can be avoided, and the service life of the fiber grating sensor can be guaranteed; and multiple spiral grooves can be arranged on the steel wire and multiple groups of fiber gratings work simultaneously so that comparison of multiple data can be performed, and accuracy of the monitoring result can be enhanced.

The invention relates to a fiber Sagner loop dynamic weighing sensor. In the sensor, a tail fiber of a light source module is connected with a first port of a fiber circulator; a second port of the fiber circulator is connected with a first port of a fiber coupler; a third port and a fourth port of the fiber coupler are connected to form a loop circuit by fibers; a fiber polarization controller, a fiber protection and enhancement sensing head and a piezoceramics actuator are connected in series to the loop circuit; a third port of the fiber circulator is connected with an input terminal of a first photodetection unit; a second port of the fiber coupler is connected with an input terminal of a second photodetection unit; an output terminal of the first photodetection unit is connected with a data acquisition card; an output terminal of the second photodetection unit is connected with the data acquisition card; the data acquisition card is connected with an input terminal of the piezoceramics actuator to form a feedback loop and connected with a signal processing and displaying system. The fiber Sagner loop dynamic weighing sensor has the characteristics of strong environmental intrusion resisting capacity, high measuring precision and accuracy and wide measuring scope.

The invention provides a mine overall precise wind measurement sensor optimal arrangement method. The mine overall precise wind measurement sensor optimal arrangement method comprises the steps that a complete mine ventilation system network topological structure diagram is built; overall ventilation resistance is measured to obtain the initial state of a ventilation system; a sensitivity matrix is obtained; air ducts are divided according to the air duct wind resistance stability and importance; air ducts are divided according to the wind volume measurement necessity, sensitivity and measurability; and according to the air duct classification result and the sensitivity matrix, a ventilation network is simplified, and the optimal wind measurement sensor arrangement scheme is found according to the simplified network through the wind volume balancing law. The mine overall precise wind measurement sensor optimal arrangement method has the advantages that (1) the wind volumes of all the air ducts can be obtained in real time through common air speed sensors and the small mounting number of the air speed sensors, and a feasible solution is provided for ventilation system online analysis state recognition and diagnosis; and (2), as for the air ducts with the low air speeds, the invention provides a mounting method for low-air-speed long-distance air accumulation air speed sensors, the measurement span of the air speed sensors is increased, and the sensitivity of the air speed sensors is improved.

The invention discloses a dynamic three-wavelength digital holographic measurement method based on a 3CCD or a 3CMOS. The dynamic three-wavelength digital holographic measurement method is characterized by comprising the steps of: utilizing a 3CCD or 3CMOS image acquisition system to carry out dynamic three-wavelength digital holographic measurement on the surface of a tested piece (S); and forming an image acquisition system by means of three CCD chips or three CMOS chips at a receiving end, so as to realize simultaneous acquisition of three wavelength holograms, obtain laser holograms corresponding to three laser wavelengths, and then acquire three-dimensional topography information of the surface of the tested piece (S). According to the dynamic three-wavelength digital holographic measurement method, three multi-wavelength holograms can be acquired at the same time, so that high-precision dynamic measurement is achieved, and due to the fact that the dynamic three-wavelength digitalholographic measurement method remarkably reduces the vibration isolation requirement of a multi-wavelength digital holographic method for environmental vibration and air disturbance, the dynamic three-wavelength digital holographic measurement method can be more widely applied to more measurement objects.

The invention discloses an acceleration measuring device and method based on a piezo-electronic effect. The acceleration measuring device comprises: a mass pendulum sheet unit, which is used for generating inertia force; a fixed loop unit, which keeps stationary relative to a carrier; a flexible quartz plate unit, which is connected to the mass pendulum sheet unit and the fixed loop unit; a deformation detection unit, which includes a nano wire and block electrodes positioned on the two ends of the nano wire respectively, wherein at least one block electrode and the nano wire together form a Schottky barrier, and the two ends of the nano wire are fixed to the mass pendulum sheet unit and the fixed loop unit through the block electrodes; a lead wire unit, which enables the deformation detection unit and a signal processing unit to be connected to form a loop; and the signal processing unit, which is used for providing voltage differences to the two ends of the deformation detection unit, measuring currents generated by the nano wire and obtaining acceleration according to the currents. A piezo-electronic effect is utilized to realize regulation and control for an interface junction zone barrier and a nano-material exhibits the quite unique mechanical performance, so the precision, sensitivity and measuring range for acceleration measuring are improved.

The invention discloses a pulse width double-moment-adding acceleration sensor circuit which comprises a meter head and a closed-loop feedback control circuit. The closed-loop feedback control circuit comprises a differential capacitance detection circuit, a digital control circuit and a pulse width double-moment-adding feedback loop. The differential capacitance detection circuit is connected to a differential capacitance sensor of the meter head. The digital control circuit receives voltage quantity outputted by the differential capacitance detection circuit, converts the voltage quantity into a digital quantity, thus generates a control quantity, and then converts the control quantity into a double-path PWM wave. The pulse width double-moment-adding feedback loop receives the double-path PWM wave and generates corresponding pulse current. The pulse current is loaded to a moment device of the meter head. The moment device generates corresponding feedback force to balance a detection mass block of the meter head. According to the circuit, the pulse width double-moment-adding feedback loop is used, a disadvantage that the dynamic measurement range of a pulse moment adding feedback loop is insufficient is overcome, and the improvement of the measurement resolution of the pulse width moment-adding acceleration sensor is facilitated.

The invention discloses a monitoring system for a cable force of magnetic flux sensors and a preparation method of the monitoring system. The monitoring system comprises a cable body, the magnetic flux sensors, a magnetoelastic instrument, a switch line concentrating box and a collecting system, wherein the cable body is formed by twisting a plurality of steel wires, and an epoxy coating layer, ahigh-strength polyester belt, inner-layer HDPE (High-Density Polyethylene), an isolating layer and outer side HDPE are sequentially arranged at the outer side of the steel wires from inside to outside; the magnetic flux sensors are distributed on the steel wires arranged on two ends of the cable body; the magnetic flux sensors are fixedly arranged in the steel wires; anchorage devices are arrangedon the two ends of the cable body; transmission signal lines of the magnetic flux sensors are lead out of the cable body; the magnetoelastic instrument is connected with the transmission signal linesof the magnetic flux sensors; the collecting system is connected with the magnetoelastic instrument. The cable force is detected by improving the parallel steel wire cable body and adopting small-bore electromagnetic sensors.

The invention discloses an anti-saturation large-current double-Hall-element current sensor, which is suitable for occasions with requirements on detection of contactor current in a larger range and small size. A magnetic circuit part locally induces the magnetic induction intensity of detection signals with the same size and direction and induces the magnetic induction intensity of interference signals with the same size and opposite directions by utilizing double Hall elements which are mutually 180 degrees in position; external magnetic field interference is eliminated through superposition, and the purpose of detecting the current is achieved through the linear relation between the magnetic induction intensity of the Hall element and the voltage; the magnetic circuit part is provided with a magnetic shielding shell made of anti-saturation magnetic material cobalt alloy and used for shielding magnetic field interference of contactor permanent magnets and adjacent binding posts of the contactor. The sensor is structurally composed of a Hall conditioning circuit, a magnetic ring, a magnetic ring air gap framework and a magnetic shielding shell. According to the invention, a high-permeability material is used as a magnetic ring material, and the magnetic ring, high-performance nylon and eight 2mm air gaps form a magnetic circuit, so that the purpose of improving the detection current range is achieved.

The invention provides a device and system for monitoring wide-range displacement of an optical fiber grating. The device comprises a shell and an optical fiber grating displacement measuring assemblyarranged in the shell, wherein the optical fiber grating displacement measuring assembly comprises a displacement sensing assembly with an input end fixedly connected with a to-be-measured target, adisplacement conversion assembly with an input end connected with an output end of the displacement sensing assembly, and a displacement measuring assembly with an input end connected with an output end of the displacement conversion assembly. The conversion assembly is utilized to convert real-time displacement of the to-be-measured target into measurable displacement within a measuring range ofthe optical fiber grating through a strain acquisition transmission assembly, the measurable displacement is converted into wavelength drift amount of the optical fiber grating, the wavelength of theoptical fiber Bragg grating is measured through a spectrometer, and the displacement amount of the to-be-measured target is calculated according to the wavelength drift amount, so that the real-time strain of the to-be-measured target is measured through the measurable range of the optical fiber grating, and the beneficial technical effect of expanding the measuring range of the optical fiber grating is achieved.

The invention provides an in-situ testing method for an unsaturated soil permeability coefficient by combining an active optical fiber temperature change-based in-situ distributed measurement method for water content with a soil water characteristic curve on the basis of a traditional transient profiling method. Long-distance and rea-time distributed measurement of soil mass volume water content can be achieved, and calculation of the unsaturated soil permeability coefficient is achieved on the basis of a measured profile of the volume water content, so that the shortcoming that a volume watercontent distribution function needs to be assumed on the basis of a water content point measurement result or the volume water content is indirectly calculated through the soil water characteristic curve in the prior art is overcome; and the calculation accuracy of the unsaturated permeability coefficient is improved.

The invention discloses a novel high-energy laser beam quality measuring device, which belongs to the field of photoelectric detection, and comprises a to-be-measured laser light source, a high-sensitivity linear array CCD, an imaging lens, a Rayleigh scatterer, a high-precision electric turntable, a high-precision electric turntable motion controller and a computer. According to the high-energy laser beam quality measurement device, in the process of realizing high-energy laser beam quality measurement, the system complexity of an existing detection device is reduced, the measurement range of the beam quality measurement device is improved, the problem of difficulty in measuring the quality of a hundred-kilowatt-level high-energy laser beam at present is solved, and meanwhile, the device has a real-time online measurement characteristic; and the device can be conveniently embedded into an industrial high-energy laser processing system and a high-energy laser weapon.

The invention relates to the mechanical metering device field and especially relates to the calibration metering device of a thin-film array-type distributed pressure sensing system. The device comprises a standard weight, a thin film array distributed pressure sensor used for detecting the standard weight, a calibration groove, a limiting clamping plate which is arranged in the calibration grooveand is cooperated with the calibration groove, and a silicone pad arranged between the calibration groove and the limiting clamping plate. A gap is arranged between the calibration groove and the limiting clamping plate. A calibration boss is arranged in the gap. The thin film array distributed pressure sensor is arranged between the silicone pad and the limiting clamping plate. The standard weight and the calibration boss are cooperated. Compared with a traditional metering tool, by using the device of the invention, the weight of a calibration weight can be applied more than 30kg, a calibration range is increased, the measurement range of the pressure sensing system is widened and the usage range of the thin film array distributed pressure sensor is enlarged.

The invention discloses a flexible pressure sensor containing a CNT composite organic material, and relates to the field of flexible film sensors. The flexible pressure sensor comprises a first flexible substrate, a first electrode, an active sensing layer, a second electrode and a second flexible substrate from top to bottom, wherein the active sensing layer is located between the first flexible substrate and the second flexible substrate, the first electrode and the second electrode are respectively fixed on the first flexible substrate and the second flexible substrate, and the first electrode and the second electrode are in a cross mode; and the active sensing layer is made of multi-walled carbon nanotubes (CNT) and polymethyl methacrylate, and the active sensing layer is manufactured in an additive manufacturing mode. The invention also discloses a preparation method of the flexible pressure sensor. According to the invention, the high-temperature-resistant and high-pressure-resistant organic composite material is used for the active sensing layer, so that the preparation process and the printing process of the slurry are optimized, and the requirements on high-temperature-resistant, wide-range and high-precision pressure sensing in industry and consumer electronics are met.