38results about "Stray field compensation" patented technology

In a magnetic field detection device capable of detecting a weak magnetic field without using a shield room, the number of components is reduced, and the circuit structure is simplified. A magnetic field detection device (1) includes: a cancellation coil (C2) wound around a winding core portion (13) of a bobbin (10); magnetic sensors (S1, S21-S24) fixed to mutually different positions of the bobbin (10); and a feedback circuit (31) that cancels an ambient magnetic field of a cancellation space by causing a cancellation current to flow through the cancellation coil (C2) in accordance with an output signal of the magnetic sensor (S1). The magnetic sensors (S21-S24) are disposed within the cancellation space. In this way, a common cancellation coil (C2) is used for the magnetic sensors (S1, S21-S24), so the number of components can be reduced, and the circuit structure can be simplified.

A soft magnetic sensor comprising a soft material containing randomly distributed magnetic microparticles and a magnetometer that can estimate force and localize contact over a continuous area. A reference magnetometer can be used to filter motion and ambient noise. Methods for locating contact and determining force comprise data analysis of the magnetometer output. In some embodiments, the sensor can localize an object prior to contact.

Various embodiments disclosed herein comprise a system. The system comprises a coil, a magnetic field sensor, and a controller. The coil generates a spatially and temporally varying magnetic field. The magnetic field sensor measures the magnetic field and a background magnetic field. The magnetic field sensor provides a magnetic field measurement and a background magnetic field measurement to the controller. The controller determines the position and orientation of the magnetic field sensor based on the magnetic field measurement and the background magnetic field measurement. The controller transfers control signaling to modify the magnetic field based on the position and orientation of the magnetic field sensor to null the background magnetic field. The coil receives the control signaling and modifies the spatially and temporally varying magnetic field based on the control signaling to null the background magnetic field.

A three-axis magnetic field detection device includes a magnetic field conversion unit for generating a stray field having a magnetic field direction according to a magnetic field direction of an outer magnetic field using magnetic particles, a magnetic field measurement unit for measuring a magnetic field direction with respect to an X-axis magnetic field and Y-axis magnetic field in relation to the outer magnetic field, and a magnetic field detection unit for detecting the X-axis magnetic field, the Y-axis magnetic field and the Z-axis magnetic field based on the stray field and the measured magnetic field direction.

A probe (303; 403) for sensing a magnetic marker, comprising a first coil set (313; 413) including a first coil of a first coil type, e.g., a sense coil (305; 405), disposed between a first pair of coils of a second coil type, e.g., a drive coil (301a, 301b; 401a, 401b) connected in series, and a balance element (317; 417) axially spaced from the first coil set (313; 413) along the length of the probe (303; 403). The balance element (317; 417) is configured or arranged to generate a sense voltage that fully offsets, partially offsets, or minimizes a sense voltage induced in one or more sense coils (305; 405) of the first coil set from the drive coil or coils (301a, 301b; 401a, 401b). A detection system is also disclosed, comprising the probe (303; 403), a magnetic field generator configured to drive an alternating magnetic field through the drive coils (301a, 301b; 401a, 401b) of the first coil set and the balance element (317; 417), and at least one detector configured to receive a signal indicative of a sensed voltage.

The invention relates to a magnetoresistive sensor (500). A magnetoresistive sensor (500) includes a layer stack (510) having at least one reference layer (512) having a reference magnetization perpendicular to a plane of the layer stack and at least one free layer (516) having a vortex magnetization. The magnetoresistive sensor (500) further comprises at least one soft magnetic shield (520) arranged adjacent to the layer stack, which soft magnetic shield is designed to reduce the influence of an external magnetic field on the free layer (516) along the shield axis (530).

A magnetoresistive sensor includes a layer stack containing at least one reference layer having a reference magnetization perpendicular to the plane of the layer stack and at least one free layer having a vortex magnetization. The magnetoresistive sensor furthermore includes at least one soft-magnetic shield arranged adjacent to the layer stack and configured to reduce an influence of an external magnetic field along a shielding axis on the free layer.

The application discloses an aviation magnetic interference suppression method, device and equipment based on double-machine multi-magnetic sensors, wherein two magnetic sensors are arranged on two magnetic exploration airplanes respectively, the two magnetic exploration airplanes are located at the same height, and the height difference between any one of the magnetic exploration airplanes and a position of a detection target is h; the two magnetic exploration airplanes are apart from each other by L; the detection distances of the two magnetic exploration airplanes are both R; it can be guaranteed that the two magnetic exploration airplanes cannot measure the target signal at the same time, so that only one of the common-mode magnetic signals of the magnetic exploration airplanes contains the target signal and the diurnal magnetic interference signal, and the common-mode signal of the other magnetic exploration airplane contains only the diurnal magnetic interference signal; the target signal after the diurnal magnetic interference signal is removed can be obtained by subtracting the common-mode signals of the two magnetic exploration airplanes; and the diurnal magnetic interference signal can be better suppressed through the method, so that the accuracy of the target signal is improved.

A method of diagnosing internal characteristics of a device includes applying a strong magnetic field to the device. The method can include reducing the strong magnetic field at a location of one or more sensors. At least one of the one or more sensors is proximate to the device. The method can include measuring induced magnetic fields around the device. The method can include measuring induced or intrinsic electrical current flow. The method can include measuring intrinsic magnetic properties. The induced magnetic fields can include diagnostic information on properties of the device and how the properties change over time. The device may be, for example, a battery, a capacitor, a supercapacitor, or a fuel cell. The presented measurement of magnetic susceptibility can be performed on materials, solutions, chemical substances, or tissue samples.

An unmanned aerial vehicle (UAV) 100 carries an optically pumped magnetometer 110 for detecting a signal from a magnetic beacon. The UAV has one or more rotors 106 which produce a noise signal. The ma

A magnetoresistive sensor (500) is proposed. The magnetoresistive sensor (500) comprises a layer stack (510) with at least one reference layer (512) having a reference magnetization perpendicular to the plane of the layer stack and at least one free layer (516) with a vortex magnetization. The magnetoresistive sensor (500) further comprises at least one soft magnetic shield (520) arranged adjacent to the layer stack, which is configured to reduce the influence of an external magnetic field along a shielding axis (530) on the free layer (516).

The invention refers to a kit for generating a predetermined magnetic field distribution in a predetermined volume in relation to a device, comprising: a plurality of sensor-source units configured to be placed around the device, wherein each sensor-source unit includes a magnetic field generating element for generating a respective magnetic field in the volume, the respective magnetic field being configured to contribute to the predetermined magnetic field distribution generated by the kit, a magnetic field sensing element for sensing the magnetic field at a surface of the volume, and a bracket to which the magnetic field generating element and the magnetic field sensing element are fixedly attached.

A magnetic field sensor according to the present invention comprises: a first element having a resistance value that changes in response to a magnetic field; a first readout circuit that outputs a first voltage corresponding to the resistance value of the first element; a second element having a resistance value that changes in response to a magnetic field; a second readout circuit that outputs a second voltage corresponding to the resistance value of the second element; wiring provided for the first element and the second element; and a control circuit that controls the current flowing through the wiring on the basis of the first voltage. The ratio of the amount of change in the first voltage with respect to the amount of change in the magnetic field and the ratio of the amount of change in the second voltage with respect to the amount of change in the magnetic field are different from each other.

A method of determining an orientation of a magnet which is pivotable about a reference position having a predefined position relative to a silicon substrate, includes: providing a silicon substrate; determining a first / second magnetic field gradient along a first / second direction; determining a first / second angle based on said first / second magnetic field gradient and a first / second correction value. A sensor device configured for performing this method. A sensor system includes such sensor device and a magnet, optionally connected to a joystick.

The invention discloses a system and method for shielding an in-vivo interventional system from an external electromagnetic (EM) distortion, the system including: at least one distortion shield having multiple magnetic field sensors; a distortion model of the distorting magnetic field produced by a distorting apparatus, a generated field model modeling the magnetic field generated by a transmitter; and a processing module, configured to: receive total magnetic field values measured by corresponding various sensors; construct, based on the received total measured fields, the distortion model, the generated field model, an energy cost function of the generated field and the distortion magnetic field possibly generated by the distorting apparatus; and determine modeled parameter values of the sensors, of the generated field and of the distortion magnetic field so that the energy cost function is minimized. The distortion shield may include a surface-tracking sensor grid.

Influence of RF noise and external magnetic field on the image quality of a portable magnetic resonance imaging (MRI) system (1) are to be avoided. This is achieved by providing a system and a computer-implemented method for determining an optimized position and / or orientation of a portable MRI system (1) for an MR imaging process in a medical environment (2), comprising at least one RF noise sensor (3), wherein the RF noise sensor (3) is configured for measuring RF noise in the medical environment (2) and to provide sensor data, at least one magnetic field sensor (4), wherein the magnetic field sensor (4) is configured to measure the external magnetic field in the medical environment (2) and to provide sensor data, a processor unit (5), wherein the sensors (3, 4) are connected to the processor unit (5), the processor unit (5) comprising at least one memory (6) for storing instructions, at least one processor (7) configured to execute the instructions to cause the following to be performed: measuring RF noise and the external magnetic field in the medical environment by means of corresponding sensors (3, 4), evaluating the sensor data and creating spatial distributions of the measured RF noise and / or the measured external magnetic field in the medical environment (2), determining a position and / or orientation of the portable MRI system (1) in the medical environment (2) for an MR imaging process based on the spatial distributions of the measured RF noise and / or the measured external magnetic field.

The application provides a kind of underwater system magnetic field test environment magnetic interference automatic compensation system, the system includes underwater multi-parameter measurement module, space-time decoupling separation module and hierarchical adaptive compensation module;The underwater multi-parameter measurement module is used for synchronous acquisition underwater multi-dimensional physical parameters;The space-time decoupling separation module is used for the magnetic field disturbance generated by each interference source in test environment is decoupled and separated and the disturbance model of each interference source is established;The hierarchical adaptive compensation module is used for hierarchical compensation based on each interference source disturbance model, and outputs the high-precision measurement result of underwater system magnetic field;The application realizes the high-precision, stable measurement of underwater system target magnetic field under complex, dynamic test environment.

The invention relates to a device for performing a work operation, in particular a welding device, comprising: at least one actuator for performing a work operation; the magnetic field source is fixed on the actuator; at least one magnetic field sensor for detecting the position of the actuator, the magnetic field sensor being designed to detect a first magnetic field strength in a first direction and a second magnetic field strength in a second direction perpendicular to the first direction; and a control and evaluation unit, which is connected to the magnetic field sensor and which is designed to identify whether the magnetic field detected by the magnetic field sensor is a magnetic field produced essentially by the magnetic field source on the basis of a comparison metric that associates the detected first magnetic field strength with the detected second magnetic field strength; and determining the position of the actuator if a positive conclusion is made on the basis of the detected first magnetic field strength and / or the detected second magnetic field strength, and issuing a control command on the basis of the determined position of the actuator.

The invention relates to a device for carrying out a work operation, in particular a welding device, comprising: at least one actuator that performs the work operation; a magnetic field source attached to the actuator; at least one magnetic field sensor for detecting the position of the actuator, wherein the magnetic field sensor is configured to detect a first magnetic field strength in a first direction and a second magnetic field strength in a second direction perpendicular to the first direction;and a control and evaluation unit connected to the magnetic field sensor and configured to identify, based on a comparison metric relating the detected first magnetic field strength to the detected second magnetic field strength, whether the magnetic field detected by the magnetic field sensor is a magnetic field substantially generated by the magnetic field source, and, if this is the case, to determine the position of the actuator based on the detected first magnetic field strength and / or the detected second magnetic field strength, and to issue a control instruction based on the determined position of the actuator.

The disclosed embodiments include a power system that includes a plurality of DC power supplies configured to receive AC power and to provide DC power to components of the charged particle system, a plurality of AC power supplies configured to provide AC power to the plurality of DC power supplies, and a controller comprising circuitry configured to perform operations that includes receiving sensor information; and for each DC power supply of the plurality of DC power supplies: determining, based on the sensor information, a load characteristic for said DC power supply, determining, based on the determined load characteristic, a value associated with an AC power supply corresponding to said DC power supply, wherein the determined value facilitates reducing a combined magnetic field leakage from the plurality of DC power supplies, and generating a control signal to cause the AC power supply to drive an output with the determined value.

An objective of the present invention is to detect a magnetic field within a detectable range even when a disturbance magnetic field exceeding the detectable range is applied.　A magnetic field detection device disclosed herein comprises: a magnetic sensor that detects a magnetic field; a magnetic field application unit that applies a bias magnetic field to the magnetic sensor; and a range adjustment unit that adjusts the detectable range of the magnetic sensor on the basis of the output of the magnetic sensor when the bias magnetic field is applied. The magnetic field detection device may also comprise: a bias setting unit by which the bias magnetic field applied to the magnetic sensor is set in a detectable range of the magnetic sensor on the basis of the result of the adjustment by the range adjustment unit; and a sensing execution unit for causing the magnetic sensor to execute sensing within the range set by the bias setting unit.

An active magnetic shield system, including an array of magnetic field sensors arranged to sense a local magnetic field. An array of magnetic field elements are arranged produce a magnetic field. Each magnetic field element has a unit coil for mounting to a plurality of surfaces arranged in at least 3 planes to define an enclosed cancellation volume, and to produce a vector magnetic field pattern.

An integrated device provides a measure of a quantity dependent on current through an electrical conductor, having: a sensing and processing sub-system: an electrical conductor conducting current: an insulating material encapsulates the sensing and processing sub-system and maintains the electrical conductor in a fixed and spaced relationship to the sensing and processing sub-system. The insulating material insulates the electrical conductor from the sensing and processing sub-system. Sensing and processing sub-system sensing circuitry includes magnetic field sensing elements adjacent the electrical conductor. The sensing circuitry provides a measure of the quantity as a weighted sum and / or difference of magnetic field sensing elements outputs caused by current through the electrical conductor adjacent the magnetic field sensing elements. A voltage sensing input senses a measure of voltage associated with the current conductor. Sensing and processing sub-system output circuitry provides an output measure of the quantity from the sensed measure of current and voltage.

In an apparatus for zeroing a magnetic field in a zeroing region in an external surrounding magnetic field, a plurality of separate magnetic field generating elements 102 are arranged at respective separate locations surrounding the zeroing region to generate respective zeroing magnetic fields extending into the zeroing region. A plurality of magnetic field sensing elements 103 are arranged at respective separate locations within the zeroing region to sense respective values ​​of the magnetic field in the zeroing region. A feedback control unit 150 controls the value of the respective zeroing magnetic field generated by each of the plurality of magnetic field generating elements by driving the magnetic field generating elements with respective currents that reduce the value of the magnetic field detected by each magnetic field sensing element to a value not exceeding a preset threshold corresponding to a preset zeroing of the magnetic field in the zeroing region in response to the value of the magnetic field sensed by the plurality of magnetic field sensing elements.

In the United States, there are approximately 17,000 new cases of spinal cord injury (SCI) each year [according to the SCI Model Systems Network]. The United States has at least 43 specialized hospitals, including at least 18 NIDILRR Model SCI Centers nationwide and 25 Veterans Affairs SCI Centers.

Systems, methods, and computer program products are disclosed for cancelling a magnetic field in a passenger region of a vehicle. Cancelling a magnetic field in a passenger region of a vehicle includes a chassis, a passenger region of the vehicle, a current carrying loop (CCL) configured to carry electricity during vehicle operation, thereby generating a magnetic field configured to radiate toward the passenger region, a sensor associated with the CCL for sensing current passing through the CCL, an electrical wire loop spatially aligned with a physical path of the CCL, and a circuit configured to: receive current sensing data from the sensor, and based on the current sensing data, determine a cancellation electrical current for providing to the electrical wire loop in order to cause a cancelling magnetic field, thereby at least reducing magnetic radiation from the CCL to the passenger region.

A system of diagnosing internal characteristics of a device includes a magnetic shield, a solenoid positioned within the magnetic shield, and one or more sensors positioned within the magnetic shield and outside the solenoid. The device is removably positioned within the solenoid and induced magnetic fields are received by the one or more sensors.