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1494 results about "Magnetometer" patented technology

A magnetometer is a device that measures magnetism—the direction, strength, or relative change of a magnetic field at a particular location. The measurement of the magnetization of a magnetic material (like a ferromagnet) is an example. A compass is one such device, one that measures the direction of an ambient magnetic field, in this case, the Earth's magnetic field.

Well deviation azimuth measurement system based on high-precision compensation algorithm

The invention belongs to the technical field of data processing, and particularly relates to a well deviation azimuth measurement system based on a high-precision compensation algorithm. The system comprises a reference vector construction part, a compensation part and a Kalman filtering measurement part. The benchmark vector construction part is used for determining a reference benchmark of a geomagnetic field and a gravitational field in the underground environment; the compensation part is used for compensating original sensor data measured by the underground sensor group, and estimating an underground initial attitude angle according to compensated accelerometer data and compensated magnetometer data in the compensated data; calculating attitude change data; according to the attitude change data, constructing a local interference field model to obtain corrected magnetometer data; and the Kalman filtering measurement part is used for modeling all error sources into state vectors, correcting measurement errors in real time through a Kalman filtering algorithm and outputting a final well deviation direction. According to the invention, the precision, the stability and the robustness of well deviation azimuth measurement are obviously improved.
Owner:QINGDAO ZITN MICROELECTRONICS CO LTD

Multi orientation door lock

In some embodiments, a method of determining whether a door is ajar may include determining an orientation of a door lock of the door, and, based on the orientation of the door lock, analyzing at least one signal from at least one of two or more proximity sensors of the door lock. The method may further include determining whether the door is ajar based at least in part on a result of the analyzing of the at least one signal. In some embodiments, a method of determining a status of a door may include receiving a first signal from a first magnetometer disposed within a door lock of the door, receiving a second signal from a second magnetometer disposed within the door lock of the door, and detecting, based on a result of an evaluation of both the first signal and the second signal, a possible attack on the door.
Owner:ASSA ABLOY RESIDENTIAL GROUP INC

High-precision attitude sensor dynamic calibration system and method thereof

The invention discloses a high-precision attitude sensor dynamic calibration system and a method thereof, and belongs to the technical field of attitude sensors. The invention discloses a dynamic calibration system and method for a high-precision attitude sensor. The dynamic calibration system comprises a data acquisition unit, a dynamic calibration unit and a calibration execution unit. The problem that the calibration effect is limited in the prior art is solved, the state of the sensor can be known more comprehensively by collecting the output data of the high-precision attitude sensor, the environmental data and the multi-source data of the accelerometer, the gyroscope and the magnetometer in real time, so that more accurate error analysis and calibration are carried out, and the calibration accuracy is improved. Modeling and error analysis are carried out by utilizing a machine learning algorithm, parameters are automatically adjusted through a model adaptive updating mechanism, error analysis can be carried out on data collected in real time so as to provide reference for subsequent dynamic calibration, and dynamic calibration operation of the high-precision attitude sensor is accurately executed according to an analysis result of the model. And high precision and high stability of attitude measurement are ensured.
Owner:CHINESE PEOPLES LIBERATION ARMY UNIT 32181

Global magnetic disturbance compensation method in aviation magnetic survey

The invention provides a global magnetic disturbance compensation method in aviation magnetic survey. The method comprises the following steps: S1, performing high-altitude calibration flight through a motion platform, and acquiring total magnetic field data based on detection data of an optical pump magnetometer; s2, obtaining geomagnetic background gradient information and obtaining geomagnetic field data based on the geomagnetic background gradient information; s3, obtaining motion platform magnetic interference data according to the total magnetic field data and the geomagnetic field data; s4, motion platform attitude information, motion platform current information and fluxgate magnetometer detection data are acquired; s5, obtaining a motion platform magnetic interference coefficient according to the motion platform magnetic interference data, the motion platform attitude information, the motion platform current information and the fluxgate magnetometer detection data; and S6, according to the geomagnetic background gradient information and the motion platform magnetic interference coefficient, performing data compensation on the total magnetic field data in real time during actual aviation magnetic measurement.
Owner:AEROSPACE INFORMATION RES INST CAS

System, Method and Apparatus for Magnetic Tracking of Ultrasound Probe and Generation of 3D Visualization Thereof

A magnetic-based tracking system for tracking an ultrasound probe. The tracking system can create a three-dimensional visualization. The tracking system can include a reference device including a reference magnet and an ultrasound probe including an ultrasound acoustic transducer or acoustic array that acquires ultrasound images. The reference device can include a magnetometer that detects a magnetic field generated by the reference magnet. The ultrasound probe can couple a first ultrasound image with a first magnetic field strength, wherein both of the first ultrasound image is received and the first magnetic field strength is detected at a first time. The system can include a console including a processor and non-transitory computer-readable medium having stored thereon a plurality of processor executed logic modules that perform operations including receiving and recording a plurality of coupling of ultrasound images and detected magnetic field strengths to generate a 3D visualization from the ultrasound images.
Owner:BARD ACCESS SYSTEMS INC

Submarine cable detection method and device based on quantum magnetometer

The invention discloses a submarine cable detection method and device based on quantum magnetometers, the device comprises a multi-frequency signal generating device and a quantum magnetic field sensing device, and the quantum magnetic field sensing device comprises a first quantum magnetometer, a second quantum magnetometer and a signal processing module; according to the method, two quantum magnetometers which are horizontally installed are used for detecting the ratio of amplitude values of alternating magnetic fields generated by two equal-amplitude alternating currents with different frequencies in a submarine cable, and the distance relation between the two quantum magnetometers and the submarine cable is judged by comparing the ratio values detected by the two quantum magnetometers. And when the ratios detected by the two quantum magnetometers are equal, the position of the motion platform is the position of the submarine cable. The quantum magnetometer is used as a core sensor, so that the influence of posture change of the motion platform on detection data jitter is reduced, and the detection precision is improved; and a multi-frequency signal detection mode is adopted, so that the difficulty of extracting the characteristic magnetic field signal generated by the submarine cable to be detected from the total magnetic field is reduced.
Owner:LONGYUAN BEIJING WIND POWER ENG TECH

Wind power generation tower pose monitoring method and system based on combination of GNSS / MEMS IMU / magnetometer

The invention discloses a wind power generation tower pose monitoring method based on a GNSS / MEMS IMU / magnetometer combination, and the method comprises the steps: carrying out the estimation of a state vector containing the position, speed, attitude error, sensor zero offset and scale factor error through error state Kalman filtering based on the GNSS / MEMS IMU combination, and carrying out the correction and fusion of GNSS and IMU data through a lever arm effect; a complementary filtering algorithm is adopted, an error vector is constructed by combining measured values of an accelerometer and a magnetometer, a gyro angular velocity is corrected through a PI controller, an attitude quaternion is recurred, a course angle is calculated, and the course angle is used as an auxiliary observed quantity to update filtering. According to the invention, by adding course information provided by the MEMS IMU and the magnetometer, the position and the attitude are comprehensively estimated, and high-precision six-degree-of-freedom pose monitoring is realized.
Owner:WUHAN UNIV

SERF atom magnetometer magnetic imaging method based on displacement modulation and optical assistance

According to the displacement modulation and optical assistance-based SERF atom magnetometer magnetic imaging method, an SERF atom magnetometer integrated with a magnetic flux guider is used as a magnetic sensor, and low-frequency magnetic field modulation is introduced to the magnetic sensor by controlling a to-be-tested sample to perform periodic infinitesimal displacement in the sensitive direction of the magnetic sensor; the modulation signal is demodulated by combining a phase-locked amplification technology, and a magnetic response signal subjected to phase-locked demodulation at each spatial position is extracted; constructing a magnetic response matrix through two-dimensional track scanning of micron-order step pitch; an image acquisition module and a reflection optical assembly are introduced for spatial registration so as to monitor the relative position in real time, and the visibility and controllability of the magnetic imaging process are guaranteed; the point-by-point detection of fT-level weak magnetic signals can be realized on the premise that an array structure is not needed; the low-frequency noise interference can be effectively inhibited, the stability and definition of direct-current and low-frequency magnetic field imaging are improved, and the method is suitable for high-resolution space imaging application of weak magnetic sources such as magnetic domain structures, nervous tissue slices and ancient rock samples.
Owner:BEIHANG UNIV

Free precession atom magnetometer modulation method and device based on optomagnetic double resonance pulses

The invention discloses a free precession atom magnetometer modulation method and a free precession atom magnetometer modulation device based on optomagnetic double resonance pulse, and relates to the technical field of magnetic field precision measurement. Firstly, pumping light passes through a light intensity modulator to generate light pulse with pulse frequency being about Larmor precession frequency and duty ratio being 50% so as to generate macroscopic polarization, then the pumping light is turned off, and the light intensity modulator generates light pulse with pulse frequency being about Larmor precession frequency and duty ratio being 50%; the method comprises the following steps: instantly applying a radio frequency pulse corresponding to the frequency of an optical pulse, controlling a spin polarization vector to a plane vertical to the direction of a magnetic field, removing the radio frequency pulse, generating a free precession signal, and extracting a Larmor precession frequency by processing the free precession signal to obtain magnetic field information. According to the free precession atom magnetometer, enhancement of free precession signals can be achieved, the dead zone of the magnetometer is reduced to be a single axis in the direction of detection light, and a new scheme is provided for application of the free precession atom magnetometer.
Owner:BEIHANG UNIV

Fusion filtering attitude estimation method based on extended Kalman filtering (EKF) and Mahony

The invention discloses a fusion filtering attitude estimation method based on EKF and Mahony, and the method comprises the steps: firstly obtaining the original data information of an IMU sensor at the current moment, carrying out the normalization of the attitude information of an accelerometer and a magnetometer, carrying out the error calculation, and compensating the error to the angular velocity of a gyroscope through a PI controller, the method comprises the following steps: performing Mahony filtering correction on an angular velocity and a corrected attitude quaternion to obtain an angular velocity subjected to Mahony filtering correction and a corrected attitude quaternion, constructing a state equation of an EKF by using the corrected attitude quaternion and a gyroscope zero offset value, and constructing an observation equation by using data of an accelerometer and a magnetometer so as to obtain an optimally estimated attitude quaternion and a gyroscope zero offset value; and finally, compensating the optimally estimated zero offset value of the gyroscope to the angular velocity correction process in the Mahony filtering process.
Owner:SHENYANG UNIV

Sensor Unit and Method for Detecting Brain-Wave-Induced Magnetic Fields

A sensor unit for detecting brain current-induced magnetic fields in an unshielded environment has a plurality of gradiometer units configured for arrangement around a head of a user. Each gradiometer unit has two magnetometers which are arranged at a fixed distance from each other. Each magnetometer has a sensor medium and is configured to detect a magnetic field strength at a measurement location by reading a spin resonance in the sensor medium depending on the magnetic field strength. The sensor unit further includes at least one excitation light source for radiating light into the sensor media of the magnetometer. The sensor unit further incudes at least one signal processing unit for determining a magnetic field gradient at a gradiometer unit as a difference of the output signals of the two magnetometers of the gradiometer unit and for detecting a time course of the magnetic field gradient.
Owner:ROBERT BOSCH GMBH

Detection of aircraft travel by a mobile device

The techniques herein are directed generally to determining or categorizing movement of a user via their user device, and specifically to detection of aircraft travel by a mobile device. In particular, according to one or more embodiments described herein, methods and / or apparatus are shown for determining that a user is in a particular mode of travel (e.g., traveling by aircraft) via a mobile device such as a smart phone by using various detected parameters including data from the sensors on that device or a sibling device such as the Inertial Measurement Unit (IMU) bearing an accelerometer, magnetometer, and / or gyroscope, and the device's atmospheric pressure barometer.
Owner:SEE OTHERS & TRAVEL MORE INC

SERF atom magnetometer double-axis magnetic field detection method and device based on pulse magnetic field modulation

The invention discloses an SERF atom magnetometer double-axis magnetic field detection method and device based on pulsed magnetic field modulation, relates to the technical field of magnetic field precision measurement, and compresses the action time of a modulation magnetic field additionally applied in the same unit period on a hot atom ensemble by replacing conventional continuous sinusoidal magnetic field modulation with pulsed magnetic field modulation. The pulse magnetic field with the duty ratio of d can reduce the spin exchange relaxation rate to 2d times of that of a conventional method under the same modulation amplitude and frequency, due to the fact that the spin exchange relaxation rate is effectively restrained, the collected polarizability response signal is obviously improved, and the polarizability response signal can be obtained through the pulse magnetic field with the duty ratio of d and the pulse magnetic field with the duty ratio of d. Low-relaxation-rate sensitivity-enhanced double-axis magnetic field measurement under a pulse modulation scheme is realized, the double-axis measurement sensitivity of a miniaturized SERF atom magnetometer is further improved, and the method has great significance in supporting leap-type development of a future array type extremely-weak magnetic imaging system and medical application thereof.
Owner:BEIHANG UNIV +1

Double-pump light semi-transparent and semi-reflective miniaturized triaxial SERF atom magnetometer device

The invention relates to a double-pump light semi-transparent and semi-reflective miniaturized triaxial SERF atom magnetometer device, which is characterized in that single pump light is guided into a probe by a polarization maintaining optical fiber; and then one beam of pump light is divided into two beams of circular polarization pump light with the same light intensity by using a half-wave plate, a polarization splitting prism, a right-angle reflector and a quarter-wave plate, and then the two beams of circular polarization pump light vertically pass through the same alkali metal gas chamber. After the pump light penetrating through the air chamber passes through the semi-transparent and semi-reflective flat beam splitter, one half of the pump light is detected by the photoelectric detector and used for extracting magnetic field information, and the other half of the pump light returns to the original path and passes through the alkali metal air chamber for the second time. According to the invention, high-sensitivity simultaneous measurement of a three-axis magnetic field of the miniaturized three-axis SERF atom magnetometer is realized, the atomic spin polarizability is enhanced, the uniformity of the atomic spin polarizability in the air chamber is improved, and the technical problem of spin polarizability uniformity in miniaturized application of the SERF atom magnetometer is solved; and the application of the array type triaxial SERF atom magnetometer in the fields of magnetocardiography, brain magnetism and the like is facilitated.
Owner:BEIHANG UNIV

Photoelectric signal conversion system of magnetometer

The invention relates to the technical field of magnetometers, and provides a photoelectric signal conversion system of a magnetometer. The photoelectric signal conversion system of the magnetometer comprises an optical lens group, a photoelectric signal conversion module and a photoelectric signal conversion module, which are sequentially arranged along a light propagation direction, wherein the optical lens group is used for carrying out light path adjustment on laser; the quarter-wave plate is used for converting the laser subjected to light path adjustment into circular polarized light from linear polarized light; the coil and the atomic gas chamber are used for receiving the circular polarized light, and the circular polarized light and alkali metal atoms in the atomic gas chamber interact in the superimposed magnetic field to form transmission light containing magnetic resonance information; the variable-focus lens group is used for performing variable-focus focusing on the transmission light; and the photoelectric detector is used for converting the focused transmission light into a voltage signal and outputting the voltage signal so as to determine the current environment magnetic field according to the voltage signal.
Owner:RES INST OF CHEM DEFENSE PLA ACAD OF MILITARY SCI

Multi-redundancy integrated navigation system

The invention relates to a redundancy integrated navigation system, which is characterized in that a modular redundancy integrated navigation system hardware platform is constructed, the redundancy integrated navigation system comprises two navigation modules with identical configuration, and each navigation module mainly comprises an array micro-electro-mechanical inertial measurement unit, a satellite navigation receiver, a magnetometer and a core processor; the array MEMS-IMU adopts a redundancy design, a plurality of MEMS-IMUs form an array, and fused angular velocity and acceleration information is obtained through fault detection and isolation and information fusion; performing fault detection and data selection on the satellite navigation receiver, and performing fault detection and data selection on the magnetometer; each navigation module carries out combined navigation calculation according to the data of the array micro-electro-mechanical inertial measurement unit, the data of the selected satellite navigation receiver and the data of the selected magnetometer; and finally, navigation data output selection is carried out. According to the scheme, system-level reliability and robustness are improved, long-time stable work of the system is guaranteed, and the method can be widely applied to pose measurement in the field of aerospace navigation.
Owner:SICHUAN INSTITUTE OF AEROSPACE ELECTRONIC EQUIPMENT

Cement-based material residual magnetism intensity detection device, detection method and evaluation method

The invention provides a cement-based material residual magnetism intensity detection device, a detection method and an evaluation method. The cement-based material residual magnetism intensity detection device comprises a magnetic shielding cylinder, a fluxgate magnetometer and a test tool, the magnetic shielding cylinder is used for shielding a magnetic field to ensure stable test environment magnetic field; the fluxgate magnetometer comprises a fluxgate probe and a fluxgate digital display meter, the fluxgate probe is used for measuring a vector value of space magnetic induction intensity at a position corresponding to the fluxgate probe, and the fluxgate digital display meter is used for displaying a residual magnetism intensity measured value measured by the fluxgate probe; the test tool is arranged in the magnetic shielding cylinder and is used for placing a sample to be tested and fixing a fluxgate probe; according to the invention, a fluxgate magnetometer and a magnetic shielding cylinder are adopted to detect the residual magnetism intensity of the cement-based material, a standardized detection process and a test method are provided for solid components, a liquid mixture and a molded test block, and quantitative characterization of the distribution rule of the residual magnetism intensity of the cement-based material is realized through fewer detection points.
Owner:CHINA CONSTR EIGHT ENG DIV CORP LTD

Defect detection sensor and defect detection method based on quantum technology

The invention discloses a defect detection sensor and a defect detection method based on a quantum technology, and relates to the technical field of defect detection.The defect detection sensor comprises a central controller, an orthogonal differential detection unit, a quantum magnetometer and a magnetic shielding cylinder; the orthogonal differential detection unit is used for collecting a first magnetic field change signal on the surface of a preset area of the preset part, transmitting the first magnetic field change signal to the quantum magnetometer and applying the first magnetic field change signal to alkali metal atoms of the quantum magnetometer; the quantum magnetometer is used for obtaining a second magnetic field change signal and sending the second magnetic field change signal to the central controller; and the central controller is used for analyzing the second magnetic field change signal and determining whether the preset area of the preset part has defects or not. According to the invention, the sensitivity and accuracy of defect detection can be improved.
Owner:PIPECHINA SOUTH CHINA CO +1

Determining continuous inclination angle

A method for determining an inclination of a wellbore can include receiving sensor data at a rig controller, wherein the sensor data comprises sensor data from a radial magnetometer, a tangential magnetometer, a radial accelerometer, and a tangential accelerometer, determining, via the rig controller, a magnetic toolface angle of a BHA based on the sensor data from the radial magnetometer and the tangential magnetometer, converting, via the rig controller, the magnetic toolface angle to a gravity toolface of the BHA based on the sensor data from the radial accelerometer and the tangential accelerometer; and determining, via the rig controller, an inclination angle based on the gravity toolface, and the sensor data from the radial magnetometer and the tangential magnetometer and determining an azimuth angle based on mapping of the earth's magnetic field vector, the inclination angle, and a high side offset angle.
Owner:NABORS DRILLING TECHNOLOGIES USA INC

Sensor calibration test system and calibration test method for UUV intelligent perception

The invention discloses a sensor calibration test system and a calibration test method for UUV intelligent perception, belongs to the technical field of underwater robots, and aims to solve the problems that the capability evaluation of the UUV intelligent perception system is difficult to realize, the credibility, the reliability and the accuracy are poor, and the UUV intelligent perception system cannot be fully matched with the actual application environment and cannot be optimized due to the existing underwater multi-mode comprehensive perception calibration mode. And the development and improvement of the intelligence of the UUV are directly influenced. The sensor calibration test system can simulate various motion modes of the underwater vehicle and the underwater target in navigation, so that a large number of calibration samples are formed, the three-dimensional imaging sonar, the underwater camera and the magnetometer can realize calibration of working parameters based on the underwater acousto-optic magnetic comprehensive beacon arranged on the underwater target, and the calibration precision is improved. After sensor calibration is completed, the system can be used for testing the calibration effect of the sensor, and the number of times and cost of sea test calibration are effectively reduced.
Owner:HARBIN ENG UNIV

Virtual fence based on animal direction

PCT designated stage expiredWO2024251941A1Pasturing equipmentOther apparatusAnimal scienceAccelerometer
The present invention relates to a method and a system for providing a virtual fence for grazing animals. The basis is tracking the position of grazing animals and exposing them to corrective signals when they move out of bounds, thereby creating a virtual fence. The invention incorporates directional sensors that measure the heading of the animal and uses this information to augment the use of position in the virtual fence. Heading can be found from the direction of the device, and is typically measured using a combination of a magnetometer, a gyroscope and an accelerometer. The position is typically measured using a GNSS device, but could also come from an inertial navigation system.
Owner:MONIL AS

Method for activating a vehicle function and associated activation device

The invention relates to a method for activating a function of a motor vehicle by means of an activation device comprising at least four ultra-wide-band communication external antenna modules and an ultra-high-frequency communication module, from an item of “hands-free” portable access equipment (SD) carried by a user, comprising an accelerometer, a gyroscope and a magnetometer, the activation of the function being triggered by detection of the presence of the user in a predetermined zone around the vehicle, and depending on an authentication result, the method comprising the following steps:s) determining an initial position of the item of access equipment with respect to the vehicle,t) measuring the values from the gyroscope, from the magnetometer and from the accelerometer,u) obtaining a value of the probability of the intention to activate a vehicle function,v) comparing the probability value with at least one predetermined threshold,w) transmitting, at ultra-high frequency from said item of equipment to said vehicle, a request to place the external antenna modules in partial or full ultra-wide-band communication operation, depending on the result of said comparison,x) activating the vehicle function, depending on an estimate of the distance between said item of equipment and the vehicle made by said external antenna modules thus activated in the ultra-wide band.
Owner:CONTINENTAL AUTOMOTIVE TECHNOLOGIES GMBH

Dynamic measurement method and system for attitude parameters of rotary steering tool

The invention relates to the technical field of drilling tool attitude dynamic measurement, and discloses a dynamic measurement method and system for attitude parameters of a rotary steering tool, and the method comprises the steps: obtaining a triaxial angular rate, a triaxial earth gravitational field component and a triaxial earth magnetic field component of the rotary steering tool in real time; determining an attitude angle priori estimated value according to the triaxial angular rate; determining an attitude angle posterior observation value according to the three-axis earth gravitational field component and the three-axis earth magnetic field component; fusing the attitude angle priori estimation value and the attitude angle posteriori observation value through iterative extended Kalman filtering to obtain a posteriori optimal attitude angle estimation result; and calculating attitude parameters according to a posterior optimal attitude angle estimation result. According to the method, adaptive fusion is carried out on the dynamic observed quantities measured by the three-axis gyroscope, the three-axis accelerometer and the three-axis magnetometer through the iterative extended Kalman filter, so that noise interference of the external environment, such as high rotating speed, strong vibration and magnetic anomaly, in the dynamic measurement process is eliminated, and the control and measurement precision of the rotary steering tool is improved.
Owner:CHINA NAT PETROLEUM CORP +1

Magnetic source positioning method based on spin-exchange relaxation-free atom magnetometer

The invention discloses a magnetic source positioning method based on a spin-exchange relaxation-free atom magnetometer, and aims to provide a high-precision brand-new solution for magnetic source positioning in a near-zero magnetic environment by performing physical modeling and least square estimation on space magnetic field distribution of a target magnetic source. The magnetometer is enabled to be simultaneously sensitive to a three-axis magnetic field, a light absorption detection method is utilized to ensure that complete three-axis magnetic field information is obtained, and the sensitivity of the three axes reaches fT / Hz1 / 2 (1fT = 10 <-15 > T) magnitude. In the positioning process, the target magnetic source is abstracted into a physical model of the magnetic dipole, and the space magnetic field information generated by the target magnetic source is obtained through the atom magnetometer, so that the long-term stability of the magnetic source positioning process and the high precision of the positioning result can be ensured in the zero magnetic environment; therefore, a high-precision magnetic positioning technical means with great potential is provided for various application scenes such as paleomagnetic sample testing and magnetic source positioning in medical research, and technical progress and application expansion in related fields are expected to be promoted.
Owner:BEIHANG UNIV

Electronic device comprising magnetometers

An electronic interactive device includes an interaction surface for use with a user borne device. The interaction surface includes a contact detection surface for detecting a device contact event with the interaction surface; a plurality of magnetometers defining a reference coordinate system and a sensing volume proximate to the interaction surface, with each of the magnetometers having a rigid spatial relationship to the other magnetometers; and processing circuitry communicably coupled to at least the contact detection surface and the plurality of magnetometers. The plurality of magnetometers perform magnetic field measurements and provide measurement data to the processing circuitry. The processing circuitry determines at least one of position and / or magnet orientation relative to a longitudinal axis of the user borne device and a distance separating the magnet and / or magnet orientation relative to a longitudinal axis of the user borne device from the interaction surface when the contact event occurs.
Owner:ADVANCED MAGNETIC INTERACTION (AMI)

Miniaturized closed-loop FID scalar atom magnetometer and implementation method thereof

The invention relates to a miniaturized closed-loop FID scalar atom magnetometer and an implementation method thereof, and belongs to the field of atom magnetic measurement. According to the method, the closed-loop working mode of the FID magnetometer is realized by utilizing a self-made electronics system, the modulation frequency of pumping light is corrected in real time, so that the magnetometer still keeps high sensitivity under a large magnetic field change rate, and the performance restriction between the dynamic range and the sensitivity of an open-loop FID magnetometer is broken through. The interaction between the self-made frequency meter and the time sequence control system is the core component of the closed loop of the magnetometer system. The device can measure a magnetic field with a large change rate at a high speed, is high in sensitivity and accuracy, and plays an important role in field magnetic measurement application.
Owner:UNIV OF SCI & TECH OF CHINA

Dynamic measurement method and system for attitude parameters of rotary steerable tools

The present invention relates to the technical field of dynamic measurement of drill tool attitude, and discloses a dynamic measurement method and system for attitude parameters of a rotary steering tool. The method includes: obtaining in real time the three-axis angular rate, the three-axis earth gravity field components, and the three-axis geomagnetic field components of the rotary steering tool; determining a prior estimate value of the attitude angle according to the three-axis angular rate; determining a posteriori observation values of the attitude angle according to the three-axis earth gravity field components and the three-axis geomagnetic field components; obtaining a posteriori optimal attitude angle estimation result by fusing the prior estimate value of the attitude angle and the posteriori observation values of the attitude angle through iterative extended Kalman filtering; and calculating the attitude parameters according to the posteriori optimal attitude angle estimation result. In this application, an iterative extended Kalman filter is used to adaptively fuse the dynamic observables measured by a three-axis gyroscope, a three-axis accelerometer, and a three-axis magnetometer, so as to eliminate the noise interference of external environments such as high rotational speed, strong vibration, and magnetic anomaly faced during the dynamic measurement process, thereby improving the control and measurement accuracy of the rotary steering tool.
Owner:CHINA NAT PETROLEUM CORP +1

Attitude estimation method based on multi-sensor fusion and adaptive filtering

The invention relates to the technical field of inertial navigation and sensor fusion, in particular to a multi-sensor fusion and adaptive filtering attitude estimation method, which comprises the following steps: S1, acquiring sensor data of a gyroscope, a magnetometer and an accelerometer, and respectively acquiring angular velocity, magnetic field direction and gravitational acceleration information; s2, angle information is obtained, and magnetometer and accelerometer sensor data are converted into attitude information; s3, carrying out weighting processing on the angle information and the attitude information through a fading memory weighting method and a limited memory weighting method; S4, carrying out filtering fusion on the weighted angle information and attitude information through an RAEKF filtering fusion algorithm; s5, an adaptive factor and a robust factor are introduced into the RAEKF filtering fusion algorithm; s6, outputting attitude angle estimation; according to the method, the theoretical contradiction that long-term drifting and stability cannot be achieved at the same time is fundamentally solved, stable precision is kept under abnormal data interference, and the robust performance is remarkably improved.
Owner:ANHUI UNIV OF SCI & TECH

Method for suppressing common-mode noise of CPT magnetometer

The invention discloses a method for suppressing common-mode noise of a CPT magnetometer, which can remarkably improve the performance of the CPT magnetometer by introducing a differential detection technology and an adaptive signal processing method. A beam of coherent laser is configured, two beams of light generated by a spectroscope respectively pass through different paths, one beam of light passes through an atomic gas chamber, the other beam of light does not pass through the atomic gas chamber, and a high-sensitivity photoelectric detector is used for collecting signals. A differential signal of two signals is generated by using a differential amplifier, so that the influence of common-mode noise is effectively eliminated. Then, the differential signal is subjected to adaptive filtering through a digital signal processor, and the signal quality is further improved. Experiments show that the method can significantly improve the measurement precision and stability of the CPT magnetometer, and has a wide application prospect.
Owner:BEIHANG UNIV +1

Unidentified aerial phenomena field disturbance detector

An unidentified aerial phenomena field disturbance detector includes an accelerometer configured to measure a gravitational field surrounding the unidentified aerial phenomena field disturbance detector; a magnetometer configured to measure a magnetic field surrounding the unidentified aerial phenomena field disturbance detector; a microwave frequency detector configured to measure a specific band of microwave frequencies surrounding the unidentified aerial phenomena field disturbance detector; a controller; and an optical indicator configured to optically communicate information to a user of the unidentified aerial phenomena field disturbance detector. The controller determines a change in the gravitational field surrounding the unidentified aerial phenomena field disturbance detector when generates gravitational field values are outside a predetermined range of non-event field values. The controller controls the optical indicator to optically communicate the determined change in the gravitational field surrounding the unidentified aerial phenomena field disturbance detector.
Owner:DIPOALA WILLIAM SAMUEL