370 results about "Magnetic disturbance" patented technology

The invention discloses an additive manufacturing surface defect, internal defect and shape composite detection device which comprises a surface defect detection system, an internal defect detection system, a shape three-dimensional measurement system and a clamping device, wherein the surface defect detection system comprises a first CMOS industrial camera; the internal defect detection system comprises an air cylinder and a detection probe; the detection probe is used for generating a magnetic field to be close to the detected surface and establish magnetic mutual action with a workpiece to form a magnetic disturbance environment; the shape three-dimensional measurement system comprises a line laser, a light filter and a second CMOS industrial camera. The device can perform real-time and comprehensive detection on the surface defect, the internal defect and the shape three-dimensional size in additive manufacturing, transmits data to an industrial personal computer for analysis, interacts with forming milling composite route planning software, and can control a shaping device in real time to perform formation and generate a milling code and control a milling cutter to perform milling on the additive manufacturing surface.

For an observer equipped with a first azimuth data source responsive to a magnetic field to deliver first azimuth data, such as a compass, and with a second azimuth data source delivering second azimuth data and which is independent of magnetic fields, such as a gyroscope. The azimuth is determined by: analyzing the first and second azimuth data to determine whether a magnetic disturbance is present, and determining azimuth selectively on the basis of: the first azimuth data, the second azimuth data, or a combination of the first and second azimuth data, as a function of the result of the comparing step. In an embodiment, the choices of azimuth data source and events such as magnetic disturbances, sensor updates, types of trajectory deduced, are stored as a history sequence over successive time windows, by analogy with a DNA sequence, and is exploited for optimizing azimuth or navigation results.

A method, consisting of generating, using a plurality of magnetic transmitters, a magnetic field in a region and introducing a field perturbing element into the region. The method includes characterizing multiple images of each magnetic transmitter in the field perturbing element, and calculating a reaction magnetic field in the region based on the characterized images. The method further includes positioning a probe in the region and measuring a perturbed magnetic field at the probe, and determining a location of the probe in response to the measured perturbed magnetic field and the calculated reaction magnetic field.

A disk drive of a perpendicular magnetic recording type uses a double-layered disk. The disk has a plurality of tracks for storing data and a non-recording region (GB area) between tracks. Not a DC magnetized pattern but an AC magnetized pattern or a random magnetized pattern is recorded in the GB area. With this structure, it is possible to prevent an influence of magnetic disturbance due to a DC magnetic field on the surface of the disk.

A method for surveying a borehole is provided. The method includes providing a tool having a magnetic field measurement device disposed thereon and positioning the tool in a borehole. Magnetic interference vectors are determined at at least two positions in the borehole by comparing the measured magnetic fields at those positions with a known magnetic field of the earth. The magnetic interference vectors indicate a direction to a target subterranean structure. Various embodiments of the invention compare the directions to the target subterranean structure with a historical survey thereof, so as to determine a distance between the borehole and the subterranean structure and an azimuth of the borehole. The surveying methodology of this invention may advantageously improve borehole surveying data obtained, for example, in relief well and/or well twinning drilling applications.

A system and method for tracking an object through a three dimensional space is provided that uses the generation and detection of various magnetic fields to provide three-dimensional location data. The integrity of the generated magnetic fields are monitored against a baseline in order to detect compromise by the unintentional introduction of a foreign metallic or magnetic object in the procedural space.

The invention discloses an automatic monitor for an angle of a base station antenna and an automatic monitoring method. The monitor and the method utilize an MEMS sensor to accurately measure a lower inclination angle of the base station antenna through the principle of a gravity accelerometer, utilize the principle of a reluctance sensitive device sensor to measure an azimuth angle of the base station antenna and calculate and correct the azimuth angle so as to eliminate the deviation caused by magnetic disturbance measured by the position of the antenna and ensure the measuring accuracy, and utilize GPRS transmission and IP transmission modes to automatically transmit the antenna angle data obtained by measuring to a network management center. The monitor and the method solve the inaccurate problems on installation and adjustment of the base station antenna in the prior modes, solve manual measurement error or instability, solve the measurement error influenced by the magnetic disturbance at the position of the antenna, solve the problem that the antenna angle change is not discovered in time, and solve the problem of time and labor wastes for acquiring the antenna angle information.

A method and system for compensating for significant soft iron magnetic disturbances in a heading reference system, such as an aircraft heading reference system, such as an integrated standby unit; or a vehicle inertial system, provides a heading correction signal to the heading reference system when a detected difference in value between a gyro heading relative to magnetic north and a magnetometer reading during a defined measurement period exceeds a predetermined acceptable threshold value of change, such as one based on the expected gyro drift over that period. Upon receipt of the heading correction signal, the gyro heading is adjusted to maintain an accurate heading relative to true magnetic north. If this threshold value is not exceeded, then the magnetometer reading is used for the heading value. This method is iteratively repeated in order to continually maintain an accurate heading and may be employed for each heading measurement axis.

The invention belongs to the field of compensation for aircraft magnetic disturbance fields, and particularly relates to an aircraft magnetic disturbance field model parameter calculating method. The aircraft magnetic disturbance field model parameter calculating method comprises the steps of measuring an environment magnetic field of a tested area, measuring a fixed magnetic field and an inductive interference field of a carrier, calculating model parameters of the inductive interference field, measuring a vortex interference field of the carrier, and calculating model parameters of the vortex interference field. The three magnetic disturbance fields of the carrier are measured and calculated gradually in the testing process, and testing pertinence is enhanced; calculating errors caused by the carrier movement coupling according to a traditional method are avoided by effectively controlling the carrier to move; calibration flying necessary in the traditional method is avoided through off-line tests and calculation, and testing resources are saved; the magnetic field of the testing environment can be effectively controlled, and errors caused by the unstable magnetic field of the tested area according to the traditional method are avoided.

The invention discloses an image-based flying drone object tracking control method, comprising the following steps: 1) photographing downwards the images of an object at a preset height and position; calculating the size of the area enclosed by the characteristic points and the central position of the area to create an object standard; 2) creating a virtual image plane in which during the flight, the camera acquires the image information of the object, obtains the acquired images and projects the acquired images onto the virtual image plane; 3) calculating the offset amounts of the projected images from the vertical direction to the relative distance of the object and from the horizontal direction to the object; 4) calculating the offset amounts of the projected images and the reference images; 5) calculating the position controller outputted instruction; and 6) generating the attitude instruction and the pull-force instruction. The control method of the invention realizes the correction of the flying position of a flying drone through the image characteristic point tracking method, which can track the object with small computations. Without the need of the magnetic compass and other sensor, the influence of electromagnetic interference can be avoided.

The invention relates to a system correction and magnetic interference compensation and fusion method for an airborne fluxgate magnetic gradient tensiometer. The method comprises the following steps: establishing an aircraft magnetic interference mode, establishing a single fluxgate error model, fusing the magnetic interference model and the fluxgate error model, establishing a magnetic gradient tensor component correction and compensation model, acquiring correction data from a uniform magnetic field area in the air, resolving a magnetic gradient tensor correction coefficient and inputting the measurement value and correction parameter of a three-axis fluxgate magnetic file into the magnetic gradient tensor component correction model, and calculating the corrected and compensated magnetic gradient tensor. The method provided by the invention has the advantages of completely covering the error factors of the airborne fluxgate magnetic gradient tensiometer and the aircraft magnetic interference type, expressing and solving in the correction model uniformly, realizing the solution of fusion of two problems of correction and compensation, and simultaneously completing the correction and compensation only by high-altitude correction and compensation flight. An iterative method is simple and practical, and a linear equation is solved by a least square method to ensure the correctness of the solution.

The invention provides a near-bit orientation dynamic measurement device and measurement method. The component of the gravity acceleration is measured through an accelerometer in the axial direction of a drilling toll, the component of the geomagnetic field is measured through a magnetometer in the radial direction of the drilling tool, and according to the strength of the local geomagnetic field, the magnetic inclination and the gravitational field overall strength data, the dynamic orientation angle is calculated. Compared with a traditional measurement while drilling (MWD), the method does not measure the geomagnetic field component in the axial direction of the drilling toll and the gravitational field component in the radial direction of the drilling toll, and the influence of the axial magnetic disturbance generated through drilling tool magnetization on the axial geomagnetic field component measuring and the influence of the centrifugal acceleration and radial vibration which are generated through rotating on the gravitational field component measuring are avoided so that dynamic measurement of the orientation angle in the drilling process can be achieved. According to the orientation dynamic measurement device, the number of used sensors is reduced to be three from six, the installation space is saved, power consumption of the sensor part is reduced, and the orientation dynamic measurement device is particularly suitable for requirement sensitive occasions of the installation size and power consumption during near-bit measuring.

The invention provides an optical anti-vibration voice coil motor capable of changing tilt shift centre, comprising a substrate, at least one elastic sheet, a lens carrier, at least three magnetic body groups and a shell. The pedestal, the shell and the magnetic body groups are connected together to form a fixed structure. The magnetic body groups are arranged in the shell; the lens carrier comprises a main body and coils arranged on the main body. The number of the coils is the same as that of the magnetic body groups. The coils and the magnetic body groups are arranged oppositely one by one. The elastic sheet is connected with the lens carrier and the magnetic body groups to form a multi-variant spring oscillator system with a spring centre. The elastic sheet is electrically connected with the coils. The direction of the electromagnetic resultant force of each coil is not faced to and not back to the spring centre, and is not parallel to an optical axis. By adjusting the size of each resultant force, the motor could be used for controlling the tilt shift of the lens to be tilted and be moved along the optical axis to achieve an optical anti-vibration function and an automatic focusing function. By adopting the above structure, the optical anti-vibration voice coil motor not only is simple in structure, and high in reliability, and reduces production cost, but also could maintain excellent image resolution and resist magnetic disturbance.

The invention discloses a detection device and a detection method of angled rotation of a camera of a mobile terminal. The detection device comprises a shell, a rotary camera component and a connecting piece used for connecting the shell and the rotary camera component, wherein a hall sensor is arranged on the shell, a magnet is arranged on the rotary camera component, the hall sensor and the magnet are arranged in parallel from top to bottom, the hall sensor is electrically connected to a signal processing circuit, the hall sensor is a digital hall sensor, setting of magnetic poles of the magnet is as follows: the pole S is upward and the pole N is downward. The connecting piece comprises a rotating shaft and an electric motor, one end of the rotary camera component and one end of the shell are connected through the rotating shaft, the other end of the rotary camera component and the other end of the shell are electrically connected through the electric motor. Quantized digital values are output by the digital hall sensor, and the output digital values are monotone increasing or monotone decreasing curves. According to the detection device and the detection method, a front camera and a back camera can be switched, the position of the rotary camera component is restored at a new call, a rotating angle is accurately detected, and the strong magnetic disturbance is effectively avoided.

The invention relates to an alternating current/direct current sensor. The alternating current/direct current sensor comprises a high-permeability transformer unit, an excitation signal generation unit, a direct current signal detection unit, a restoring circuit unit, an alternating current signal processing unit and a power amplification unit. The high-permeability transformer unit comprises a first magnetic core, a second magnetic core, a first magnet exciting coil, a second magnet exciting coil, a third magnetic core, a primary coil, a secondary coil and an auxiliary coil, wherein the first magnetic core and the second magnetic core are independent of each other; the first magnet exciting coil and the second magnet exciting coil are wound around the first magnetic core and the second magnetic core respectively; the third magnetic core, the first magnetic core and the second magnetic core are overlapped so as to form an integrated magnetic core; the primary coil, the secondary coil and the auxiliary coil are wound around the integrated magnetic core. The performance of the alternating current/direct current sensor is improved remarkably. The alternating current/direct current sensor has the advantages of being low in power dissipation, high in magnetic disturbance resistance capacity, simple in structure, light, high in response speed, high in flexibility, good in interchangeability, convenient to install, calibrate, adjust and maintain, and the like.

The invention belongs to numerical simulation of discharge of a Tokamak device in the field of magnetic confinement controlled nuclear fusion, and relates to a simulation method for controlling a newclassic tearing mode through resonance magnetic disturbance in Tokamak. According to the current data in the Tokamak upper coil assembly, the Biot-Savart law is used for solving an induced magnetic field; integrating is performed to obtain an expression of a polar magnetic flux corresponding to the induced magnetic field according to approximation of a large ring diameter ratio; a Fourier transform pseudo-spectrum method is utilized to transform magnetic flux into components of different moduli to obtain three-dimensional distribution of the components in a tokamak median form, the three-dimensional distribution is coupled into a magnetofluid equation, and the Crank-Nicosolson method is utilized to solve the evolution of the magnetic field with the resonance magnetic disturbance along with time, so that the influence of the magnetic field on the new classical tearing mode is studied. The method can simulate the physical processes of new classic mode locking, inhibition, field penetration and the like of the tearing mode, is high in calculation efficiency and relatively good in numerical stability, and is an efficient numerical method capable of accurately simulating an experiment.

A magnetic memory array comprises a plurality of magnetic memory cells, a magnetic shielding disposed adjacent to at least one of the magnetic memory cells to reduce magnetic interference with respect to another of the magnetic memory cells, and an insulator disposed as to separate at least a portion of the magnetic shielding from the at least one magnetic memory cell. The magnetic shielding may be a magnetic shield layer, patterned magnetic shield materials, and/or magnetic particles embedded in the insulator.

The invention discloses a self-adaptive adjustment method of an aeromagnetic interference compensation coefficient, relating to the aeromagnetic interference compensation technology field and particularly relating to a regulation method of the aeromagnetic interference compensation coefficient. The self-adaptive adjustment method of the aeromagnetic interference compensation coefficient is aimed to solve the problem that the in the prior art, the aeromagnetic interference compensation solving matrix is not accurate in the aeromagnetic interference compensation coefficient which is caused by morbidness. The self-adaptive adjustment method of the aeromagnetic interference compensation coefficient comprises steps of expressing the magnetic interference generated by an airplane as HI, performing extension on a T-L model, performing fusion on a geomagnetic field HE and a magnetic interference HI, setting an initial value Theta 0,P0, calculating a final compensation coefficient vector Theta 1 of first collection data according to a formula of Theta m=Theta m-1+Km (ym-Delta m Theta m-1), obtaining a final compensation coefficient vector Theta N until N times of collection data are finished, enabling the estimate value of a compensation coefficient vector to be Theta <^ >=Theta n, and using a Theta <^ > as a self-adaptive regulation result of the aeromagnetic interference compensation coefficient. The self-adaptive adjustment method of the aeromagnetic interference compensation coefficient is applicable to the adjustment of the magnetic interference compensation coefficient.

The invention discloses a compass positioning optimization method and system for a mobile terminal. The method comprises the steps that when positioning of a compass of the mobile terminal is accurate, acceleration sensor data are read at the moment, and the data serve as benchmark data for accurate positioning of the compass; when a magnetic object is close to the mobile terminal, the precision of a magnetic sensor is affected, and acceleration sensor data are read at the moment; the benchmark data read when the compass positioning is accurate are compared with acceleration sensor data read when the precision of the magnetic sensor is affected; if the two groups of data are approximated to each other, the magnetic sensor produces no response to magnetic disturbance, and positioning of the compass is kept; if not, the magnetic sensor produces a response to the magnetic disturbance, and a user is prompted to calibrate the magnetic sensor. The system comprises a compass precision value detection module, a first data reading module, a second data reading module and a data comparing module. The compass positioning optimization method and system enable the compass to achieve accurate positioning even when the precision of the magnetic sensor is affected.

The invention provides a piezoelectric generating set based on human body kinetic energy stimulation, comprising a plurality of piezoelectric generating composite boards, wherein each piezoelectric generating composite board comprises a metal supporting board and a piezoelectric element; the piezoelectric element is connected with the upper surface of the metal supporting board; the metal supporting board and the piezoelectric element both have a circular arc shape structure; and piezoelectric generating composite boards are mutually overlaid and connected. The device also comprises an elastic supporting body which is connected with the lower surface of the metal supporting board. The invention also provides a generating method of the piezoelectric generating set, which utilizes human body kinetic energy as stimulation to generate electricity. The piezoelectric generating set has the advantages of no magnetic cores, no copper conductor winding coils, no magnetic disturbance, high generating efficiency, environment protection, sanitation, convenient carrying and the like, can be installed on insoles and soles and can be used for supplying power to portable electronic accessories, such as mobile phones, MP3, radios and the like.

The invention provides a device for testing a magnetic suspension characteristic of a single high-temperature superconductor. The device is characterized by comprising a fixed bracket composed of a top plate, a base and a fixed rod, wherein the fixed bracket is vertically placed or horizontally placed, so that suspension and guide forces of the single high-temperature superconductor are conveniently tested; a through hole is formed in the middle of the top plate; a movable rod penetrates through the through hole and is driven by a servo motor to move up and down; the motion displacement of the movable rod is measured by a displacement sensor; a liquid nitrogen low-temperature container is fixedly connected onto the base; a force sensor for testing the suspension and guide forces of a suspension system is connected to a lower part of the liquid nitrogen low-temperature container; and a permanent magnet body and the displacement sensor are arranged together. Compared with the prior art, the device has the advantages that static suspension and guide forces of the system and dynamic suspension and guide forces under external magnetic disturbance can be tested on the same device, the device has diversified structural test contents and is simple in structure, small in volume and convenient to use, and defects of single test content, complex structure, complexity in operation and high cost are avoided.

A method and system for compensating for soft iron magnetic disturbances in multiple heading reference systems, such as aircraft heading reference systems, integrated standby units; or vehicle inertial systems, detects and provides a heading correction signal to the error prone heading reference system when a detected difference in value between a gyro heading relative to magnetic north and a magnetometer reading during a defined measurement period exceeds a predetermined acceptable threshold value of change, such as one based on the expected gyro drift over that period. Upon receipt of the heading correction signal, the gyro heading is adjusted to maintain an accurate heading relative to true magnetic north. If this threshold value is not exceeded, then the magnetometer reading is used for the heading value. This method is periodically repeated in order to continually maintain an accurate heading and may be employed for each heading measurement axis.

A method and apparatus for continuous, non-intermittent, detection of vehicles based on a light detector for detecting a change in illumination when a vehicle arrives or departs, and on a use of the light detection to activate a magnetic sensor, a sensitivity of which is adjusted to detect only those magnetic disturbances sufficiently large to be able to be attributed to a vehicle which is over the sensor. Both the light detector and the magnetic sensor are connected directly to a digital controller without a need for active electronic components or their own or a shared power supply source. The light detector may be fixed or portable, wireless or connected by cables, and may operate independently or as part of a sensor network.