32 results about "Gradiometer" patented technology

The present application relates to a kind of rotation accelerometer gravity gradiometer attitude error post-processing compensation method, comprising the following steps: step 1, original motion data is acquired using the inertial measurement unit fixed with gravity gradient sensor, and the positioning and speed information provided by radio navigation are combined to complete original data acquisition;Step 2, the attitude error of gravity gradient sensor in the measurement process is optimally estimated;Step 3, based on the coordinate transformation matrix of gravity gradient tensor under different coordinate systems, the error compensation of gravity gradient measurement value is carried out, and finally the gravity gradient measurement data after attitude error compensation is obtained.The present application can be used in dynamic measurement environment, and the measurement information of carrier motion is measured using gyroscope and accelerometer, the attitude error of gravity gradient measurement component is estimated and compensated offline with high precision, and then the dynamic measurement precision of rotation accelerometer gravity gradiometer is improved.

A sensor, including: a gradiometer including a plurality of magnetoresistors, the gradiometer being configured to generate a sensing signal in response to a magnetic field that is at least in part produced as a result of an electrical current flowing through a conductor; and electronic circuitry configured to detect an electrical current consumption of the gradiometer, compare the electrical current consumption against at least one of a first threshold and a second threshold, and output an indication that the sensor is subject to tampering based on an outcome of the comparison.

Disclosed are methods and devices for detecting retained surgical items or other objects having a magnetic signature within a corpus of a patient. The device can comprise a handle, a shaft extending from the handle, and a distal sensing portion positioned distally of the shaft. The distal sensing portion can comprise one or more gradiometers comprising a plurality of magnetometers. The device can further comprise one or more output components configured to generate a user output to alert a user of a detected object.

The application relates to the technical field of magnetic detection, in particular to a method and a test system for coupling a magnetic gradiometer and a SQUID to improve sensitivity, which comprises the following steps: deploying at least one set of magnetic gradiometer probe arrays in a superconducting shielding environment to obtain original magnetic gradiometer tensor data streams of a target area; feeding a multi-channel SQUID front-end input coil through a superconducting transmission line; completing magnetic flux locking and amplification to generate a preliminary signal by the SQUID; suppressing environmental and SQUID background noise by using an adaptive digital noise reduction processor to obtain a high-fidelity magnetic gradiometer signal; and generating a high-resolution magnetic gradiometer distribution map through gradient reconstruction and spatial resolution enhancement. The superconducting shielding environment combines array acquisition to suppress external interference and retain complete tensor characteristics, and the superconducting transmission line combines a multi-channel SQUID to reduce transmission noise and cumulative error, so that the signal is closer to the original state, and the SQUID locking sensitivity and amplification fidelity are improved. The application improves the sensitivity of magnetic gradiometer detection and the accuracy of target identification.

The invention belongs to the technical field of precision measurement, and relates to an indoor movable base testing device for a horizontal tensor gravity gradiometer and application of the indoor movable base testing device. The device comprises a control processing module, and a gravity gradient standard field generation module and a motion simulation module which are respectively connected with the control processing module, the motion simulation module and the gravity gradient standard field generation module are both fixed on a foundation, and the gravity gradient standard field generation module comprises an electric displacement table; a pair of attraction source assemblies arranged in an orthogonal mode is fixed to the electric displacement table. The horizontal tensor gravity gradiometer to be measured is arranged on the motion simulation module and located between the pair of gravitation source assemblies; the control processing module is used for driving the motion simulation module to simulate the environment of the movable base, and is also used for enabling the gravitation source assembly to translate on the electric displacement table and generating a gravity gradient standard field dynamically matched with the motion of the gravitation source assembly. According to the invention, the performance verification of the horizontal tensor gravity gradiometer under the condition of simulating the movable base can be realized, and the test cost and period are reduced.

A biomagnetic sensor that incorporates an integrated active noise cancellation unit that uses a gradiometer to remove ambient magnetic noise from a detection signal obtained from a tunnelling magnetoresistive (TMR) sensor unit that is indicative of a magnetic field adjacent to biological tissue. The ambient magnetic noise can thus be removed in real time at a front end of the sensor (e.g. as part of circuitry in the sensor body itself). The active noise cancellation technique proposed herein may be effective enough to enable the biomagnetic sensor to be used in an unshielded environment (i.e. an environment that is subject to the Earth's magnetic field, for example), which widens significantly the potential uses for the sensor.

This invention discloses a method and system for geological and mineral exploration, belonging to the field of geological and mineral technology. The solution includes three core steps: First, a quantum gravity gradiometer array is constructed at the target mining site to collect quantum gravity data in each area to mark drilling target areas that meet the criteria. Second, fluid data from nanorobots tracking each drilling target area is analyzed to determine the nanorobot penetration plan and collect ore-forming fluid data. Finally, a three-dimensional fracture network model of the target mining site is constructed based on the ore-forming fluid data. By calculating the total clustering coefficient corresponding to the model, the design and analysis of the mining plan for the target mining site are completed. This solution integrates quantum technology and nanorobot tracking technology, and through data acquisition and modeling analysis, provides an innovative technical path and systematic analytical framework for the scientific formulation of geological and mineral exploration and mining plans.

A biomagnetic field sensor for detecting magnetic fields from the human body comprises: a tunnelling magnetoresistive (TMR) sensor unit 104 to measure a biological magnetic field; a gradiometer unit 1

Described herein are methods and apparatuses to provide accurate measurement of relatively small magnetic fields under ambient conditions while being worn on an ambulatory subject. These methods and apparatuses may allow accurate and reliable detection of biomagnetic fields from organs such as the brain, heart, and muscles, using a magnetometer, and in particular, using an Acoustically Driven Ferromagnetic Resonance (ADFMR) sensor. These methods and apparatuses may incorporate one or more of: a synthetic gradiometer, flexible and / or thin-film / foil shielding, and / or denoising.

The utility model discloses an auxiliary device for slope measurement of an urban and rural road model, which relates to the technical field of slope measurement and comprises a gradiometer, the bottom end of the gradiometer is movably sleeved with a protective frame, grooves are symmetrically formed in the inner wall of the bottom end of the protective frame, and the inner walls of the grooves are fixedly connected with fixed shafts. The outer sides of the fixing shafts are movably sleeved with rotating plates, and the sides, close to each other, of the rotating plates are fixedly connected with overturning plates correspondingly. The protective frame and the turnover plate are arranged, so that the measuring surface at the bottom of the gradiometer can be covered and protected through mutual matching of the protective frame and the turnover plate when the gradiometer is not used, and the measuring surface of the gradiometer can be effectively prevented from being damaged due to friction and collision in the transportation process; and a threaded rod and a rotating block are arranged, and in the using process, through mutual cooperation of the threaded rod and the rotating block, the protective frame and the connecting rod can be detached, so that replacement of the damaged protective frame is achieved.

The present application provides a device, system and method for detecting weak electromagnetic signals of a sample, comprising a driving module, N Helmholtz coils, a low-temperature container, two SQUID modules, a first signal processing module and a second signal processing module; N is a natural number greater than 1; the driving module provides driving signals for each Helmholtz coil, each SQUID module includes a SQUID galvanometer and a gradiometer; the input end of each SQUID galvanometer is connected to each gradiometer; the input end of the first signal processing module is connected to the output end of each SQUID galvanometer, and outputs a first processing signal to the second signal processing module; the second signal processing module determines whether the processing signal produces random resonance. The present application can realize synchronous detection, that is, the sample of the substance to be tested dissolved in the solvent and the sample containing pure solvent are tested synchronously at the same time, further avoiding the error caused by the time difference caused by separate testing.

The embodiment of the application discloses a data compensation method, device, equipment and storage medium, and the method comprises the steps of establishing a target interference compensation model of a towed superconducting full-tensor magnetic gradient measurement system for a pod platform, wherein the target interference compensation model comprises a SQUID magnetic gradiometer measurement item, an interference compensation item and a sensor self-interference correction item; wherein the interference compensation item excludes residual magnetic interference items of the pod platform, and the interference compensation item comprises a magnetosensitive interference item represented by a first-order derivative of an earth magnetic field component and an eddy current interference item represented by a second-order derivative of the earth magnetic field component; the sensor self-interference correction item is used for representing the imbalance degree and unknown offset of the SQUID magnetic gradiometer; a target function is constructed based on the target interference compensation model; the SQUID magnetic gradiometer measurement value and the SQUID magnetometer measurement value are input into the target function, and a compensation coefficient is obtained by using a symmetric overrelaxation iteration method; and the towed superconducting full-tensor magnetic gradient measurement system is compensated based on the compensation coefficient.

Size, weight, and cost of an atomic magnetic sensor vacuum chamber, and thus an atomic magnetometer and / or an atomic magnetic gradiometer, is reduced by using at least one photonic integrated circuit (PIC). The at least one PIC is configured to receive an optical signal, e.g., from a laser, and to distribute the optical signal to at least one set of two or more grating coupled surface emitters. Each grating coupled surface emitter is configured to collimate, direct, and emit, along a direction of emission, an optical beam, derived from a portion of the optical signal, to an optical detector.

To provide a buried object magnetic survey system capable of improving the quality of measurement data by suppressing false recognition of small detection as noise and discriminating clear noise.SOLUTION: The buried object magnetic search system includes a sensor parallel arrangement frame 10 suspended and towed from a search barge. The sensor parallel arrangement frame 10 has a ladder shape. A plurality of both coil type magnetic gradiometers 11 and a plurality of cesium magnetometers 12 are alternately provided corresponding to each step of a ladder. Further, the sensor parallel arrangement frame 10 is provided with a motion sensor 13.SELECTED DRAWING: Figure 2

The invention discloses an external coincidence precision evaluation method and equipment for a gravity gradient vertical horizontal component, and the method comprises the steps: enabling a shipborne cold atom absolute gravimeter and a full-tensor gravity gradiometer to be installed on the same ship, controlling a measurement ship to sail at a constant speed along a preset measurement line in the north-south direction or the east-west direction, and carrying out the synchronous measurement, obtaining gravity vertical component data output by a shipborne cold atom absolute gravimeter and vertical horizontal component data output by a full-tensor gravity gradiometer; performing filtering processing on the gravity vertical component data and the vertical horizontal component data, and performing point-by-point calculation on the filtered gravity vertical component data and the corresponding position data by adopting a midpoint difference method to obtain a calculation value of a vertical horizontal component; and respectively counting the total number of effective measuring points of the measuring lines in the north-south direction and the east-west direction, and calculating the root-mean-square error of the vertical horizontal component data and the corresponding calculation value, the root-mean-square error being the external coincidence precision of the vertical horizontal component of the full-tensor gravity gradiometer.

The invention discloses a miniaturized vacuum system for an atomic gravity gradiometer, which comprises an upper vacuum cavity, an upper getter I, an upper getter II, an ion pump I, an ion pump II, an upper copper pipe, an upper atomic source, a lower vacuum cavity, a lower getter I, a lower getter II, a lower copper pipe and a lower atomic source, the vacuum system can be divided into an upper atom trapping area, an upper interference area, an upper detection area, a cavity connecting area, a lower atom trapping area, a lower interference area and a lower detection area according to functional area division, and the upper detection area and the lower detection area are each provided with at least one detection window used for detecting the number of atoms. The mode of combining the getter and the ion pump is adopted to replace a large-size combination pump, the size of the vacuum system of the atomic gravity gradiometer is remarkably reduced, meanwhile, by reasonably distributing the positions of the pump sets, the vacuum degree consistency of the upper cavity and the lower cavity is effectively improved, the common-mode rejection effect of the atomic gravity gradiometer is enhanced, and the gravity gradient measurement precision is improved.

A system and a method for estimating a position of a vehicle. The vehicle includes a gradiometer. The method includes calculating a gravity vector using a gravity spatial derivative generated by the gradiometer and a plurality of body velocities generated by a body velocity source, calculating a gravity potential based on the gravity vector, and estimating an inertial measurement unit (IMU)-based position using the gravity vector, a body acceleration, and a body attitude. The method includes estimating a gravity vector-based position using the gravity vector and estimating a gravity map-based position using the gravity potential and one or more gravitational maps. The method includes estimating the position of the vehicle based on the IMU-based position, the gravity vector-based position, and the gravity map-based position, and controlling at least one of the vehicle and a second vehicle based on the position of the vehicle.

The invention discloses a universe intelligent sensing stiff composite pile construction quality control method which comprises the following steps: before construction, arranging a quantum gravity gradiometer array and an electromagnetic signal receiving and transmitting device on a site, and obtaining universe gravity field baseline data and underground dielectric constant distribution before construction; according to material design, iron powder or titanium powder and other electromagnetic sensitive materials are doped into cement soil, the mass ratio is 0.01%-5%, and excitable-responsive intelligent cement soil is formed; sensing in construction; and verification after construction: based on quantum-electromagnetic cooperative detection and an AI prediction model, directly outputting a pile body integrity, bearing capacity and settlement characteristic evaluation report to replace traditional static load test and core drilling detection. The quality is controllable, the construction period is shortened, and sedimentation is reduced.

This invention relates to a circuit for measuring the output frequency signal of a cesium optically pumped horizontal gradient meter. The circuit includes a signal conditioning module and a frequency measurement module. The raw signals output from two cesium optically pumped magnetometers are processed by the signal conditioning module, and the external frequency signal to be measured is input to the FPGA. An externally sourced, voltage-triggered, temperature-controlled crystal oscillator square wave signal serves as the frequency measurement reference signal input to the FPGA. The rising edge of a standard signal is used as an enable flag to synchronously start counting the three signals. Within a specified frequency measurement gate time, the three signals are counted synchronously, and the number of rising edges is recorded. Using an external temperature-controlled crystal oscillator as the frequency measurement reference signal effectively avoids the drift and irregular jitter of the pulse signal caused by temperature changes in the onboard crystal oscillator of the FPGA, thus effectively improving the frequency measurement accuracy and circuit stability.

The pulsed pump magnetometer (PPM) is a new type of magnetometer with much higher dynamic range, linearity, and sensitivity than all other types of magnetometers. These features allow more faithful subtracting and cancelling sources of magnetic noise, enabling high quality biomagnetic measurements. Using an array of PPM sensors enables high quality measurements of biomagnetic signals even in magnetically noisy, real-world conditions like medical offices. Arrays of PPM sensors improve upon pulsed magnetic gradiometers in providing higher sensitivity per sensor and superior noise rejection through noise decorrelation and covariance modeling. Arrays of PPM sensors enable localization and imaging of biomagnetic sources.

The present application relates to a kind of direct coupling DC SQUID readout electronics, including gradiometer antenna and SQUID sensor, the gradiometer antenna is superconducting contact with the input coil of SQUID sensor, and form superconducting flux transformer with it, the output of the SQUID sensor is connected with the input of conversion amplifier, the output of the conversion amplifier is connected with the input of integrator, the SQUID sensor is connected with the output of bias voltage module, the output of the integrator is analog output terminal, the output of the integrator is connected with the input of feedback gain module, the output of the feedback gain module is connected with feedback coil, the feedback coil is connected with SQUID sensor inductance.The present application makes output voltage more linear.

This invention discloses a method for monitoring the relative gravity of surface subsidence during coal mining. It involves deploying quantum gravity reference stations around the subsidence area, arranging relative gravimeters in a grid pattern within the basin, and arranging fiber optic gravity sensor chains in the underground roadway. Simultaneously, a UAV equipped with a cold atom gravity gradiometer performs periodic scans. Based on real-time data, a gravity field-mass migration model is established, correlating coal extraction volume, changes in rock density, and surface gravity anomalies. Wavelet multi-scale decomposition is used to eliminate geological background interference, and hydrological correction is applied, incorporating water level and porosity to optimize gravity variation values. When the corrected gravity variation exceeds a threshold, the azimuth of rock fracture is calculated using the gravity gradient tensor. Equivalent extraction thickness is derived based on gravity variation inversion, and the surface subsidence morphology is dynamically predicted using a subsidence basin model. A state vector is constructed by combining gravity, gradient, and deformation data, and multi-source fusion prediction is achieved through a filtering algorithm.

The invention discloses a method and equipment for measuring external coincidence precision of shipborne gravity gradient, and the method comprises the steps: enabling a shipborne cold atom absolute gravimeter and a shipborne gravity gradiometer to be installed on the same ship, carrying out the synchronous measurement according to a preset measurement network, obtaining a first gravity abnormal data grid outputted by the shipborne cold atom absolute gravimeter, and obtaining a first gravity abnormal data grid; the two different horizontal gravity gradient component data are output by a ship-borne gravity gradiometer; performing two-dimensional Fourier transform on the two different horizontal gravity gradient component data to obtain a gravity potential frequency spectrum, calculating a frequency spectrum of gravitational acceleration through the gravity potential frequency spectrum, and performing inverse Fourier transform on the frequency spectrum of the gravitational acceleration to obtain a second gravity anomaly data grid; carrying out difference operation on the first gravity anomaly data grid and the second gravity anomaly data grid point by point to obtain a difference grid, carrying out sample standard deviation statistics on the difference grid, and verifying whether the distribution of the difference grid accords with normal distribution or not; if the normal distribution is met, the standard deviation is the external conformance precision of the ship-borne gravity gradiometer.

The utility model discloses a road side slope gradient measuring instrument which comprises a measuring instrument body, a dial is arranged on the top of the measuring instrument body in a penetrating mode, a level tube is rotatably connected to an inner cavity of the dial, and a scale rotating wheel is rotatably connected to the top of the measuring instrument body. Guide rails are fixedly connected to the front surface and the back surface of the measuring instrument body, and detachable measuring panels are slidably connected to the surfaces of the guide rails. According to the utility model, the shifting block is shifted to enable the sliding block to slide towards the square direction of the spring, so that the spring is extruded to contract, the detachable measuring panel can be pulled out for replacement, the shifting block is loosened after replacement is completed, the spring is stretched, and the spring pushes the sliding block to be attached to the detachable measuring panel; therefore, the purposes that the measuring surface of the gradiometer can be replaced and fixed through the clamping and fixing structure, the measuring result of the gradiometer is prevented from being affected by the abraded measuring surface, and the measuring precision of the gradiometer is guaranteed are achieved.

A measuring arrangement for determining the electrical conductivity of a measuring fluid comprises a gradiometer including an excitation coil and a first and a second receiver coil. The first and second receiver coils and the measuring fluid are inductively coupled to the excitation coil. The measuring arrangement includes a measuring circuit for exciting the excitation coil, for detecting an electrical signal from the receiver coils, and for deriving the electrical conductivity of the measuring fluid from the signal. All coils consist of a conductive material that has a resistance temperature coefficient which at 20° C. is less than 3.93*10−3 K−1.

The pulsed pump magnetometer (PPM) is a new type of magnetometer with much higher dynamic range, linearity, and sensitivity than all other types of magnetometers. These features allow more faithful subtracting and cancelling sources of magnetic noise, enabling high quality biomagnetic measurements. Using an array of PPM sensors enables high quality measurements of biomagnetic signals even in magnetically noisy, real-world conditions like medical offices. Arrays of PPM sensors improve upon pulsed magnetic gradiometers in providing higher sensitivity per sensor and superior noise rejection through noise decorrelation and covariance modeling. Arrays of PPM sensors enable localization and imaging of biomagnetic sources.

The invention belongs to the technical field of electric power detection, discloses a wide-range anti-interference current measurement system and method based on a quantum magnetic gradiometer, and aims to solve the problem that precision and interference resistance are difficult to consider in the prior art. The system comprises a hollow metal tube which is of a central symmetry structure and is connected in series with a to-be-tested circuit; the quantum magnetic gradiometer is fixed at the central position in the hollow metal tube and comprises two quantum magnetic sensor probes which are arranged in the cross section of the hollow metal tube in a central symmetry manner; the light source module is connected with the quantum magnetic gradiometer through an input optical fiber; the signal processing and display module is connected with the quantum magnetic sensor probe through an output optical fiber; and the synchronous control module is respectively connected with the light source module and the signal processing and displaying module. While wide-range and high-precision current measurement is realized, common-mode noise and background interference in a complex electromagnetic environment are effectively suppressed, and the stability and reliability of measurement are remarkably improved.

The invention belongs to the technical field of magnetic field measurement, discloses a magnetometer magnetic field measurement method, system and equipment based on phase difference and a medium, and aims to solve the problems that an existing multi-probe magnetic gradiometer system is high in complexity and high in cost, and the measurement stability is easily influenced by the performance and synchronization precision of a frequency meter. The method comprises the following steps: acquiring a corresponding relation between phase difference and voltage through a first magnetometer and a signal generation device, and determining a conversion coefficient between magnetic field intensity and voltage; connecting an output signal of the second magnetometer to a radio frequency coil of the first magnetometer, acquiring a phase difference between the output signal of the second magnetometer and the output signal of the first magnetometer, and converting the phase difference into a second voltage; and calculating the magnetic field intensity of the to-be-measured magnetic field according to the second voltage and the conversion coefficient. According to the invention, a multi-channel synchronous acquisition technology and a complex differential circuit are not needed, and the system structure is greatly simplified, the cost is reduced and the measurement stability is improved while the noise suppression level equivalent to that of the traditional magnetic gradient technology is maintained.

The application provides a three-dimensional gradiometer and a biomagnetic detection device. The three-dimensional gradiometer comprises a non-magnetic structure, coils, a non-magnetic sleeve, a chip carrier and a chip. Two ends of the non-magnetic sleeve are connected with the non-magnetic structure and the chip carrier respectively. The coils comprise a first coil group, a second coil group and a third coil group. Each coil group is distributed in different dimensions and is symmetrically wound on the non-magnetic structure. Each coil group comprises detection coils and compensation coils which are arranged in an upper and lower spaced manner and are connected in series. The chip carrier is a multi-prism, and the bottom surface of the chip carrier adjacent to the non-magnetic sleeve is a regular polygon structure. A plurality of chips are arranged on different surfaces of the chip carrier in a one-to-one correspondence and are connected with each coil group in a one-to-one correspondence. The three-dimensional gradiometer can measure three dimensions of a magnetic field and remove environmental noise through a clever structural design, and can greatly improve the detection precision of a magnetic signal.

The invention provides a magnetic method detection method and system capable of adaptively adjusting a measuring line direction, belongs to the technical field of ocean detection technologies, particularly provides a method for determining the putting depth of a magnetometer, carries out magnetic detection according to the determined minimum putting depth and a measuring line interval d, and proposes construction of an expansion interference model and a state vector. And real geomagnetic field calculation and total vector direction calculation results are obtained through combined online estimation of establishment of an extended measurement model containing a complete interference term and adaptive volume Kalman filtering. The direction of the measuring line is adjusted in a self-adaptive mode based on the tidal current direction and the change of the direction included angle, the detection method is optimized, and the detection precision and the resolution ratio are improved.