1812 results about "Magnetic sensing" patented technology

The invention discloses a nondestructive testing method for internal defects of a concrete structure fusing big data feature extraction and deep learning. According to the method, through multi-source data collaboration and dynamic feature fusion, the accuracy and robustness of concrete structure defect detection are remarkably improved. In a data processing link, ultrasonic electromagnetic induction infrared thermal imaging data and the like acquired by a multi-source nondestructive testing technology are subjected to collaborative preprocessing, so that the influence of noise interference and environmental fluctuation is eliminated, and standardized input is provided for feature extraction. The dynamic weight distribution network further combines the relevance of each modal feature in a historical defect sample, adjusts fusion weights of different modals in real time, reinforces ultrasonic features with great contribution to cavity recognition or infrared features sensitive to cracks, effectively compresses redundant information, and improves the accuracy of cavity recognition. According to the method, features and data-driven deep features of the fused feature vectors are manually designed at the same time, so that the limitation of single-modal data is avoided, and a model can more accurately capture multi-dimensional features of defects.

The invention provides a lossless helical blade wear real-time monitoring system and detection method, and relates to the technical field of helical blade wear detection, and the lossless helical blade wear real-time monitoring system comprises at least one group of sensing assemblies and a processing terminal. Each sensing assembly comprises at least one sensing unit and is arranged on a barrel of the spiral conveyor, and each sensing unit is suitable for obtaining the magnetic induction intensity change in the process that a spiral blade is abraded in a detection range or rotates towards and away from the sensing unit and outputting a detection signal; the processing terminal is in communication connection with the sensing unit and is suitable for obtaining a detection curve representing the change of the relative position of the spiral blade and the sensing unit according to the detection signal and comparing the detection curve with a preset calibration data set so as to determine the abrasion loss of the spiral blade in the detection range according to the matching degree of the detection curve and the calibration data set.

The three-axis Hall magnetic sensing chip comprises a magnet gathering body, a first Hall element group and a second Hall element group, the first Hall element group and the second Hall element group are arranged in a plane at intervals, the magnet gathering body is arranged on Hall elements, and the orthographic projection of the magnet gathering body on a Hall plane has a first direction symmetry axis and a second direction symmetry axis which are orthogonal. The first Hall element group comprises two first Hall elements which are connected in a contrast difference mode, wherein the magnetic induction centers of the two first Hall elements are located on a first-direction symmetric axis and are symmetrically arranged relative to a second-direction symmetric axis. The second Hall element group comprises two second Hall elements which are located on the same side of the first direction symmetry axis and are symmetrically arranged relative to the second direction symmetry axis, and the magnetic induction centers of the two second Hall elements are perpendicular to the connecting line between the orthogonal intersection points of the first direction symmetry axis and the second direction symmetry axis; the magnetism gathering body is located on one side of the connecting line of the two magnetic induction centers. According to the invention, a high inter-axis signal rejection ratio is realized, and the Z-axis signal can be directly output.

The invention discloses a multi-mode unmanned aerial vehicle system and method for detecting the thickness of a bridge concrete protection layer. The system comprises a multi-mode unmanned aerial vehicle platform, a contact type mechanical arm, an electromagnetic induction steel bar detection module, a wireless data transmission module, an area array laser radar module and a binocular camera module. The contact type mechanical arm is installed on the unmanned aerial vehicle platform and used for executing contact type nondestructive testing. The electromagnetic induction steel bar detection module is installed at the tail end of the contact type mechanical arm and used for making contact with the bridge surface and measuring the thickness of a steel bar protection layer. The wireless data transmission module is installed on the unmanned aerial vehicle platform and used for returning the video of the view angle of the unmanned aerial vehicle to the ground station operation platform in real time, and the ground station operation platform observes and controls the unmanned aerial vehicle according to the returned video; the area array laser radar module is installed below the contact type mechanical arm and used for carrying out pose estimation and obstacle avoidance during adsorption mode switching. The binocular camera module is arranged at the front end of the contact type mechanical arm and used for collecting images of a detected area and conducting unmanned aerial vehicle autonomous positioning.

The utility model discloses a brushless servo motor easy to install and debug, which comprises a shell, a rotor, a stator and an encoder assembly, and is characterized in that the rotor comprises a rotating shaft and a magnetic ring; the shell comprises a shell and a first end cover; the stator comprises a stator core and a winding; the magnetic ring is an M-pole magnetic ring; the encoder assembly comprises a PCB and a magnetic induction device, the magnetic induction device comprises N groups of Hall sensors, and N is 1 or 2; each group of Hall sensors comprises two Hall sensors, and one Hall sensor rotates 90 degrees around the center line of the rotating shaft to reach the position of the other Hall sensor; each Hall sensor is eccentrically arranged relative to the center line of the rotating shaft, and a gap is formed between each Hall sensor and the magnetic ring in the axial direction of the rotating shaft. According to the utility model, the Hall sensor directly senses the magnetic field of the magnetic ring of the rotor to determine the angular position of the rotor, an independent sensing magnet does not need to be arranged on the rotor, the structure is simple, and the installation process is simplified.

The invention discloses a wide-dynamic-range diamond NV color center magnetic sensing method and system, and the method comprises the steps: (1) calibrating the initial resonant frequency and magnetic sensing coefficient of a diamond NV color center in an initial magnetic field environment; (2) in a to-be-measured magnetic field environment, a microwave generator applies frequency-modulated microwaves to the diamond NV color center with the current resonant frequency as the center frequency; demodulating the fluorescence signal in real time by using a phase-locked detection technology to obtain an error signal; calculating the detuning amount of the center frequency in real time according to the error signal and the magnetic sensing coefficient, and further calculating the variable quantity of the magnetic field intensity; meanwhile, the detuning amount is fed back to a microwave generator to track the resonance frequency of the diamond NV color center; and (3) continuously and repeatedly executing the step (2) to realize wide-dynamic-range magnetic field measurement. The method has the advantages of wide dynamic range, high detection capability on strong and weak field mixed signals in a complex application scene and the like while giving consideration to the magnetic sensing sensitivity.

The invention relates to a magnetic saturation evaluation method and system for a magnetic component in a strong magnetic field environment, and the method comprises the steps: constructing a target component model of a to-be-tested magnetic component according to a target geometric parameter and a target material parameter, and respectively setting excitation and boundary conditions of the target component model according to the target working current parameter and the target working environment magnetic field parameter, and performing simulation. The method comprises the following steps: acquiring simulated BH data of a target position in a target component model and corresponding simulated working environment magnetic induction intensity, and determining that the target component model reaches a magnetic saturation state according to the simulated BH data of the target position; and taking the corresponding simulated working environment magnetic induction intensity as a simulated saturated external magnetic field threshold value of the to-be-tested magnetic component. According to the embodiment of the invention, analog simulation of the saturation external magnetic field threshold of the to-be-tested magnetic component in the magnetic field environment is realized, and important support can be provided for model selection application and design optimization of the magnetic component in the high-intensity magnetic field environment.

The invention discloses reservoir underground pore connectivity transformation simulation equipment, a reservoir underground pore connectivity transformation simulation system and an evaluation method. The equipment comprises a rock core transformation clamping device, a first magnet, a second magnet, a nuclear magnetic resonance signal controller, a storage and collection tank and a fluid displacement device, wherein a magnetic induction coil is arranged in the rock core transformation clamping device, and the first magnet and the second magnet are oppositely arranged on the two sides of the rock core transformation clamping device; the nuclear magnetic resonance signal controller is electrically connected with the first magnet, the second magnet and the magnetic induction coil respectively and is used for controlling the magnetic field intensity formed by the first magnet, the second magnet and the magnetic induction coil and measuring a nuclear magnetic signal of a rock core sample in the rock core transformation clamping device; the rock core modification clamping device comprises a fluid inlet, the fluid inlet is communicated with the storage and collection tank, and the fluid displacement device is connected with the storage and collection tank, so that fluid is displaced into the rock core modification clamping device under the action of the fluid displacement device, and modification and evaluation on the pore connectivity of the rock core sample under different fluid pressures are realized.

The invention discloses a battery module active and passive combined ejection structure, an energy storage system and a method, relates to the technical field of battery energy storage safety structures, and provides an active and passive combined battery electric / thermal magnetic induction ejection structure design based on electromagnetic induction and magnetic transformation characteristics of soft magnet materials at specific temperature. The ejection safety of the battery pack is guaranteed, the active triggering monitors abnormal information such as voltage and temperature through the BMS, and the system master controller issues an instruction to execute ejection; passive triggering can be automatically triggered without a BMS instruction by utilizing the magnetic transformation characteristic of a soft magnet at a specific temperature (thermal runaway characteristic temperature), the limitation of only depending on BMS active control in the prior art is solved by utilizing an active and passive combined triggering mechanism, and the passive triggering can be automatically triggered even if BMS monitoring is not accurate or a sensor has a fault through mutual complementation of the two mechanisms. And the fault battery pack can still be isolated through passive triggering, so that the potential safety hazard is greatly reduced.

The invention provides a diagnosis method and system suitable for magnet current in a quasi-ring symmetrical star simulator, and relates to the technical field of star simulators, and the method comprises the steps: setting a target voltage range, and finally outputting the mutual inductance coefficient, total number of turns and sectional area parameters of a coil; utilizing an electromagnetic induction conversion algorithm to generate an original measurement signal; an original measurement signal is input into an integrator through a shielded wire to obtain a proportional voltage which is strictly proportional to the current, and the proportional voltage is transmitted to a data acquisition interface; performing analog-to-digital conversion on the proportional voltage received by the acquisition interface to generate a discrete sequence, calculating a conversion coefficient by combining a target mutual inductance coefficient and a fixed time constant, and finally restoring a digital current signal; and inputting the digital current signal to an upper computer to realize dynamic waveform display, and outputting key boundary parameters to a plasma experiment module. The method has the advantages that the method can adapt to complex changes of magnet current, and enough measurement precision and response speed can be provided in a low-parameter experiment.

The invention discloses a J-A model parameter identification method, system, equipment and medium based on RBF and an improved brownish bear algorithm, and belongs to the technical field of power system optimization, and the method comprises the steps: building a Jiles-Atherton hysteresis reverse model of a current transformer, determining a to-be-identified parameter vector, and building a model with a root-mean-square error between actually measured magnetic field intensity and simulated magnetic field intensity as a target function, training a radial basis function neural network model, expanding data through linear interpolation processing, obtaining a predicted magnetic induction intensity value, inputting an objective function and radial basis function prediction data into an improved brownish bear optimization algorithm, and iteratively optimizing model parameters through hierarchical population position updating and fitness evaluation until convergence conditions are met. And outputting an optimal parameter identification result. According to the method, high-precision and high-efficiency identification of hysteresis model parameters is realized, the generalization capability and robustness of the system are improved, and reliable technical support is provided for hysteresis characteristic analysis of a complex physical system.

The invention discloses a current sensing measurement device and method, a storage medium and electronic equipment, and the device comprises an AC detection module which is used for sensing an AC current and outputting an AC current analog signal; the direct-current compensation module is used for acquiring magnetic induction intensity generated by a direct-current component of the detected current and outputting a differential voltage analog signal; the compensation module is used for outputting compensation current which is equal to the direct-current component in size but opposite to the direct-current component in direction based on the compensation control signal output by the signal processing module so as to offset direct-current magnetic flux generated by the direct-current component; and the signal processing module is used for calculating a direct current component, a compensation current and an alternating current based on the alternating current analog signal and the differential voltage analog signal, and outputting the compensation control signal based on the direct current component. According to the invention, direct current interference can be effectively suppressed, air gap nonlinear errors can be compensated, influences caused by environmental changes and equipment aging can be adapted, high precision and high reliability of a measurement system can be maintained during long-term operation, and the requirement of high-precision field calibration can be met.

The invention discloses an infrared instrument metal lens cone online defect detection device, and relates to the field of metal lens cone defect detection.The infrared instrument metal lens cone online defect detection device specifically comprises a partition plate and a base box installed at the bottom of the partition plate, a positioning plate is fixedly installed on the back face of the top of the partition plate, and a heat preservation mechanism used for preventing the metal lens cone from cooling too fast is arranged on the front face of the positioning plate; a heat supply mechanism for heating the metal lens barrel is arranged on one side of the top of the partition plate; the electromagnetic induction heater is used for rapidly heating the metal lens barrel, and a hot air flow inner wall blowing heat dissipation mechanism is combined, so that the problem of detection errors caused by uneven heat dissipation of the inner wall and the outer wall of the metal lens barrel is effectively solved, and particularly, the capability of detecting internal inclusion and welding defects is improved; the thermal shock damage caused by direct contact of cold air is avoided in a hot air flow heat dissipation mode, the quality of the lens barrel is protected, in addition, through the synergistic effect of the heat preservation mechanism and the shielding unit, the heat dissipation process of the metal lens barrel is further controlled, and the stability of the detection environment is ensured.

The invention relates to a current measurement method and device, computer equipment, a storage medium and a program product. The method comprises the following steps: acquiring the magnetic field intensity of the two sides of a monitoring point at the current moment through a first magnetoresistive sensor and a second magnetoresistive sensor which are deployed on the two sides of the same monitoring point of a power transmission line to obtain first magnetic induction intensity and second magnetic induction intensity; wherein the first magnetoresistive sensor and the second magnetoresistive sensor are located in the same electromagnetic environment; according to the first magnetic induction intensity, the second magnetic induction intensity and the error coefficient of the first magnetoresistive sensor and the second magnetoresistive sensor, the initial current value of the monitoring point at the current moment is determined, and the influence of the hysteresis effect on the current value is eliminated; and Kalman filtering processing is carried out on the initial current value of the monitoring point at the current moment to obtain the target current value of the monitoring point at the current moment, so that the accuracy of the measured current value is further improved.

The invention provides a 90-degree Halbach array-based magnetic coupler for a reaction kettle, which comprises a sealing cover cylinder, an outer magnet support sleeve is rotatably connected to the outer side of the sealing cover cylinder, a plurality of outer magnets are arranged on the outer magnet support sleeve, an inner magnet support sleeve is rotatably connected to the inner part of the sealing cover cylinder, and a plurality of outer magnets are arranged on the inner magnet support sleeve. A plurality of outer magnets are arranged on the outer magnet supporting sleeve, a plurality of inner magnets are arranged on the inner magnet supporting sleeve, the outer magnets and the inner magnets are arranged according to a 90-degree Halbach array, the outer magnets are arrayed according to the fact that the magnetic induction intensity of the inner sides of the outer magnets is enhanced by the 90-degree Halbach array, and the inner magnets are arrayed according to the fact that the magnetic induction intensity of the outer sides of the inner magnets is enhanced by the 90-degree Halbach array. The invention further provides an optimal design method of the magnetic coupler, and an optimal design combination is found by adopting a multi-target parameterization optimal design method. The invention solves the technical problems of low magnetic field intensity between air gaps, low magnetic steel utilization rate, low maximum transmission torque and low design and development method efficiency of the existing magnetic coupler, and belongs to the technical field of magnetic drive reaction kettles.

The invention belongs to the technical field of magnetic suspension motors, and discloses magnetic suspension fan motor winding temperature monitoring equipment and an early warning method. The method comprises the following steps: laminating a preset temperature-sensitive ferromagnetic material and a magnetic suspension fan motor stator iron core according to a preset process to obtain a composite iron core; deploying a high-frequency excitation system on the composite iron core, adjusting the number of turns of a micro-coil of the high-frequency excitation system according to the target magnetic field intensity, collecting real-time excitation current, and analyzing to obtain magnetic induction intensity; analyzing the magnetic induction intensity through multi-physics field coupling iteration to obtain a winding three-dimensional temperature field; performing temperature gradient analysis on the three-dimensional temperature field, performing temperature early warning according to an analysis result, and dynamically adjusting motor operation parameters; according to the invention, the comprehensiveness of temperature monitoring of the magnetic suspension fan motor winding, the timeliness of early warning and the accuracy of cooling control are effectively improved, and safe and stable operation of the motor under complex working conditions is guaranteed.

The invention discloses a visual tactile sensor based on a magnetic imaging principle. The visual tactile sensor comprises a shell, an image acquisition module, a magnetic pole display film, an elastic body and a magnetic film, the magnetic pole display film, the elastic body and the magnetic thin film are arranged in the shell from top to bottom, and the image acquisition module is located above the magnetic pole display film and used for acquiring an image of the magnetic pole display film; when the sensor is used for pressure sensing, the position with the maximum gray level variation of the magnetic pole display film image is the pressure acting position, and the pressure is equal to the result that the gray level variation of the magnetic pole display film image is divided by the magneto-optical conversion coefficient of the magnetic pole display film and the product thereof. The magnetic induction intensity in the center range of the surface of the magnetic film, the initial distance between the magnetic film and the magnetic pole display film and the equivalent elastic coefficient of the magnetic film and the elastic body are related. The sensor converts a mechanical signal into a magnetic field signal and then converts the magnetic field signal into an optical image, high-sensitivity sensing of tiny pressure is achieved, and meanwhile the sensor has the higher signal-to-noise ratio, stability and anti-interference capacity.

The invention relates to the field of buried facility monitoring, and discloses a piezoelectric cantilever vibration sensing and super capacitor self-powered energy closed-loop operation method and system, and the method comprises the steps: building a star array composed of a master pile and a slave pile, and configuring a TDMA time slot and an uplink message length; the slave pile collects a vibration signal through a piezoelectric cantilever, the vibration signal is rectified by a piezoelectric rectification energy taking module and then charges a super capacitor, and the voltage state of the two ends of the super capacitor is obtained; when the voltage state reaches a preset upper threshold, the boosting module supplies power to the processing circuit and the transmitting circuit of the slave pile, and the processing circuit generates a four-byte feature code; the slave piles send four-byte feature codes in a magnetic induction link according to TDMA time slots, the master pile receives and aggregates the four-byte feature codes sent by the multiple slave piles, completes positioning and fusion according to the arrival time difference, and returns the four-byte feature codes to the platform through LoRa and 4G, and the platform completes storage and output according to the four-byte feature codes and a positioning result. According to the invention, end-side cloud connection and replicable deployment can be realized, and low-frequency vibration acquisition and buried communication are adapted.

This invention relates to a device and method for in-situ detection of seeding spacing and depth based on magnetic field induction, belonging to the field of intelligent agricultural machinery equipment technology. It includes a mounting base at the rear end of a precision seeder, a vertical rod mounted on the mounting base, and a cutting shovel at the lower end of the vertical rod. The cutting shovel has two opposing cutting plates, and the opposing sides of the two cutting plates are respectively equipped with multi-dimensional high-precision magnetic sensing modules for detecting magnetic induction intensity information. It also includes a controller and a GPS wireless speed measuring device. The GPS wireless speed measuring device is used to measure the real-time operating speed of the precision seeder. The controller is electrically connected to both the GPS wireless speed measuring device and the multi-dimensional high-precision magnetic sensing modules. This application can solve the problems of current methods for detecting seeding spacing and depth after sowing operations, which rely on manual labor, have poor detection accuracy, and low detection efficiency.

The embodiment of the utility model relates to the technical field of automobile control valves, and discloses a valve driving device and an electronic valve.The valve driving device comprises a rotor, a circuit board, a first magnetic inductor and a second magnetic inductor, the circuit board is arranged on the outer side of the circumference of the rotor, and the rotor can rotate around the axis direction of the rotor relative to the circuit board; the first magnetic sensor is arranged on one side of the rotor and used for sensing the radial magnetic flux of the rotor, and the second magnetic sensor is arranged on one side of the rotor in the radial direction of the rotor and used for sensing the tangential magnetic flux of the rotor. In this way, according to the embodiment of the invention, the rotation angle of the rotor can be obtained through decoding calculation according to the radial magnetic flux signal and the tangential magnetic flux signal. Changes of different components of the same magnetic field are sensed through the first magnetic sensor and the second magnetic sensor, comprehensive assembly errors are effectively avoided, the orthogonality of two paths of sensing signals is improved, and the calculation precision of angle decoding is improved.

The invention relates to a tunnel reluctance current sensor structure and temperature parameter optimization method and system, and the method comprises the steps: arranging an annular magnetic core, forming symmetrically distributed air gaps in the annular magnetic core, placing a tunnel reluctance current sensor in each air gap, and forming a double-air-gap magnetic circuit structure; constructing a magnetic field consistency coefficient according to the average magnetic induction intensity, the minimum magnetic induction intensity and the maximum magnetic induction intensity of the air gap center area, and performing optimization solution on structural parameters of the double-air-gap magnetic circuit structure by taking minimization of the magnetic field consistency coefficient as a target; respectively establishing a measurement channel and a reference channel according to the double-air-gap magnetic circuit structure obtained through optimization solution; multiple times of voltage signal acquisition are carried out through a reference channel under different injection reference currents and different temperature environments, and a temperature compensation factor is calculated, so that gain parameters of an amplifier in a measurement channel are adjusted. Compared with the prior art, the anti-interference capability and the measurement sensitivity of the system can be greatly improved.

The invention discloses a highly packaged magnetic sensing chip based on an NV color center, and the chip comprises a packaging housing (1) which is provided with a packaging pedestal and chip pins. The chip is characterized in that the chip also comprises an NV color center diamond (2) which is arranged on the packaging base; the laser diode bare chip (3) is arranged on the packaging base, and the light-emitting side of the laser diode bare chip faces the NV color center diamond; the microwave transmission microstrip line (4) is arranged between the interior and the edge of the packaging base and is electrically connected with the chip pins; the first photoelectric detector assembly (5) is arranged on the NV color center diamond and used for collecting fluorescence signals.

The invention provides intelligent traffic vehicle identification monitoring equipment, which comprises three-dimensional sensing network construction, a multispectral visual center, and combined pickup through a camera and thermal imaging equipment. The multi-dimensional sensing fusion system and the millimeter wave radar array form a space electromagnetic field sensing network, and a geomagnetic induction coil matrix is deployed; according to the decision center system architecture, an AI decision engine constructs a'perception-cognition-decision 'three-order processing pipeline; a human-vehicle-road-environment-event five-dimensional association network and a closed-loop evolution mechanism are constructed by a smart evolution center and a traffic meta-knowledge graph through an ontology modeling technology, and a sensing-decision-execution-evaluation closed-loop evolution system is constructed. All-weather accurate sensing is achieved, the measurement accuracy is kept through the multispectral fusion technology and equipment automatic calibration, the traffic light automatically generates a continuous green light band to improve the traffic efficiency, navigation software synchronizes control information in real time, and vehicle owners can avoid temporary closed road sections.

The invention relates to the technical field of intelligent illumination control, in particular to an illumination control system based on voice recognition and magnetic control, which comprises a voice trigger module, a magnetic disturbance path construction module, a behavior orientation recognition module, a voice and magnetic action joint recognition module and an illumination state control module. According to the invention, through frame segment division and sound wave feature extraction of the continuous audio stream, effective voice instructions can be accurately identified in a complex voice environment, and magnetic induction signals form a disturbance path map through magnetic flux direction mapping of a time sequence, so that careful tracking of space magnetic field changes is realized; according to the method, non-contact space operation has high direction sensitivity, the movement trend of a user in the space is effectively described aiming at angle change analysis of a magnetic flux disturbance path, the accuracy of behavior recognition is improved, the accuracy and safety of equipment operation are ensured on the premise that the space behavior intention of the user is met, and the user experience is improved. And the man-machine interaction efficiency and the use experience under multiple scenes are greatly improved.

The invention relates to the field of display screens, discloses a self-adaptive adjusting support for an outdoor display screen, and aims to solve the technical problems that an existing outdoor display screen is single in display form, insufficient in immersion experience, high in energy consumption and low in intelligence. The display screen comprises an immersive film watching room, the core of the immersive film watching room is a film watching room outer frame, an annular film watching space is formed by a plane display screen and a curved surface display screen in the frame, elastic bent rods are arranged on the upper side wall and the lower side wall outside the frame, and flexible permanent magnet rods on the elastic bent rods are correspondingly and magnetically attracted with inner permanent magnet blocks on straight rods of the curved surface display screen; a telescopic motor drives an elastic bent rod to deform through a fixed rod transmission chain, drives a curved display screen to synchronously adjust the curvature through magnetic attraction linkage, and is matched with a side telescopic door to realize film watching space adaptation; a magnetic sensitive detection layer and a partition driving circuit are integrated on the flat panel display screen, and an invalid display area is dynamically closed to save energy; according to the device, an'advertisement mode 'and an'immersion mode' are automatically switched through infrared induction and a main controller.

An alternating-current electromagnetic field stress measurement system, comprising: an excitation signal generation module, an alternating-current electromagnetic field stress measurement stress probe, a signal amplification circuit, an A / D conversion circuit and a processor, wherein the excitation signal generation module is used for loading a sinusoidal alternating-current signal to an excitation coil of the alternating-current electromagnetic field stress measurement stress probe, such that a periodically changing electric field is generated on a measured magnetic object; the alternating-current electromagnetic field stress measurement stress probe is used for sequentially routing a stress characterization signal, which is detected from the measured magnetic object, through the signal amplification circuit and the A / D conversion circuit, and then sending the stress characterization signal to the processor; and the processor is used for processing the received stress characterization signal by using an optimized J-A model in which an implicit equation originally characterizing a change in the magnetization intensity or magnetic induction intensity along with stress is made explicit, so as to calculate the stress of the measured magnetic object. The alternating-current electromagnetic field stress measurement system can monitor the stress increase trend in real time, and notice potential dangers in time. Further comprised is an alternating-current electromagnetic field stress measurement method and a computer program for executing the alternating-current electromagnetic field stress measurement method.

The invention relates to the technical field of motor monitoring, in particular to a permanent magnet motor fault simulation test system and a fault monitoring method thereof, and the system comprises a test resistance obtaining device which is used for obtaining equivalent resistance parameters of a target model permanent magnet synchronous motor under different fault levels; the fault levels are divided according to magnetic induction intensity information of the motor in a working state; the simulation test system constructs an operation control environment of the target motor based on a current control strategy of the target motor, and introduces equivalent resistance parameters under different fault levels as test resistance variables in the operation control environment; according to the scheme, equivalent resistance parameters corresponding to different fault levels are injected in an environment of simulating a real working current control strategy of a target motor through a pre-constructed simulation test system, and massive current dynamic data covering multiple working conditions are efficiently generated; and therefore, a targeted motor fault monitoring model can be quickly constructed.

The invention discloses an anti-magnetic suspension accelerometer device based on a quasi-zero stiffness structure and a measurement method, and belongs to the field of precise instruments and meters. The device comprises a support, an axial displacement platform, magnetic conductive soft iron, an upper-layer pyrolytic graphite sheet, a lower-layer thin bismuth wafer, a capacitance displacement sensor and a permanent magnet array, wherein an anti-magnetic suspension system, a magnetic rigidity regulation and control system and a displacement detection system are arranged in the support; the anti-magnetic suspension system is composed of an upper-layer pyrolytic graphite sheet, a lower-layer thin bismuth wafer and a permanent magnet array, the magnetization directions of an inner ring and an outer ring of the permanent magnet array are opposite, a suspension element is suspended by virtue of anti-magnetic force and gravity balance, and quasi-zero stiffness is realized through positive and negative stiffness offset; according to the regulation and control mode, the magnetic field of the air gap where the suspension element is located is adjusted by adjusting the distance between the magnetic conductive soft iron and the permanent magnet, and the magnitude and gradient of magnetic induction intensity in all directions are changed, so that the magnetic rigidity is regulated and controlled, and efficient and accurate regulation and control of the sensitivity and the measuring range of the anti-magnetic suspension accelerometer are achieved. Therefore, the application range of the anti-magnetic suspension accelerometer is expanded.

The invention belongs to the technical field of encoder signal processing, and particularly relates to an encoder capable of realizing non-contact rotation through a measurement magnetic ring of a magnetic induction technology and a TMR magnetic induction read head encoder, performing digital signal processing through a DSP under the driving of a high-speed motor, and integrating signal direct-current bias, amplitude phase difference correction and temperature detection through a program. High-precision position feedback is achieved by subdividing and encoding sine and cosine orthogonal signals inductively output by the measuring magnetic ring, the RS485 protocol communication has the advantages of being high in anti-interference capacity and rich in communication protocol, state monitoring information can be obtained while position information is obtained, motor parameters and encoder parameters can be stored in a built-in mode, and high-precision position feedback can be achieved through a driver. The upper computer is used for reading and modifying, operation is convenient, and the application range is wide.

The invention discloses a result verification method for a transcranial magnetic stimulator calibration device, and relates to the technical field of medical equipment detection, and the method comprises the following steps: collecting pulse magnetic field parameters outputted by a TMS therapeutic instrument in real time through constructing a multipath parallel magnetic field distribution perception array composed of a plurality of coil type magnetic field sensors; designing a three-dimensional calibration platform to perform multi-dimensional dynamic calibration on the magnetic field distribution sensing array, calibrating the relationship between the induced electromotive force and the magnetic induction intensity of the sensor, and verifying whether the measurement error is less than + / -0.1% or not; and comparing the actually measured magnetic field data with the human brain magnetic field distribution data simulated by the finite element simulation model, analyzing the difference value between the simulation data and the actually measured data, and correcting the system according to the data deviation degree. According to the transcranial magnetic stimulator calibration device and the result verification method, real-time acquisition and high-precision calibration of dynamic parameters are realized through a multi-path synchronous magnetic field sensing array, and the calibration reliability is verified based on finite element simulation and actually measured data comparison.