Abstract: A superconductive quantum interference device (SQUID) system is provided for measuring the alternating current (AC) magnetic susceptibility of material at a single frequency or a mixing frequency from multiple frequencies, such as mf1+nf2, where f1 and f2 are two excitation frequencies of two primary coils. The system includes a magnetic-flux sourcing unit for producing an AC magnetic flux on a sample and a magnetic-flux reading unit for reading the induced magnetic flux from the sample via a magnetic flux transformer. The magnetic-flux reading unit includes a SQUID set for detecting the induced magnetic flux, so as to obtain the magnetic susceptibility of the sample in converting calculation.

Abstract: A system and method for measuring volumes and areas using electromagnetic induction techniques. A current is generated and fed into one of two coil assemblies to induce voltage into another coil assembly to provide accurate values for volume or area.

Abstract: At least one time-varying signal is applied to a plurality of coil elements in cooperative relationship with and spanning different portions of a vehicle. The coil elements generate an associated plurality of magnetic field components that interact with the vehicle. At least one detection circuit generates a detected signal responsive to signal components from the coil elements so as to provide for detecting a change in a magnetic condition of the vehicle.

Abstract: The present invention provides a method for measuring hydrogen concentration in an electrically conductive material, such as a nuclear fuel rod, comprising calibrating an eddy current probe at a plurality of hydrogen concentrations; measuring eddy currents at a plurality of positions along an electrically conductive material; and calculating a hydrogen concentration in the electrically conductive material at each of the positions along the electrically conductive material. The present invention also provides a system for measuring hydrogen concentration in a nuclear fuel rod, comprising an eddy current probe; a nuclear fuel rod calibration standard; a data handling system for collecting data generated by the eddy current probe and for performing calculations using the data. The system may be utilized in-situ and may comprise a movable probe mount configured to hold the eddy current probe and to traverse the calibration standard and the nuclear fuel rod to be measured.

Abstract: Disclosed is an assembly and method for locating magnetic objects or objects that can be magnetized, with the objects being located in non-magnetic media. To increase the detection depth for such objects and to clearly register their shape, position and structures on single detection planes, at least one sensor is arranged in a primary magnetic field of a magnetic field generator and the magnetization distribution of the magnetic field is uniform in the vicinity of the corresponding senor or its local profile is known.

Abstract: A method of measuring the retention force of a biomedical specimen coupled to a carrier includes the measurement of the force required for magnetically decoupling the specimen from the carrier. In one embodiment, the method includes the steps of providing the specimen with an electrically conductive structure; creating an external alternating magnetic field near the specimen; increasing the amplitude and/or frequency of the magnetic field; detecting the start of the movement of the specimen on the carrier; and calculating the retention force of the specimen by determining the applied magnetic force on the basis of the parameters of the magnetic field. In other embodiments, the magnetic field may remain constant and the biomedical specimen may be moved through the field at varying speeds.

Abstract: The present invention is directed towards an automated apparatus and method for determining the pass through flux (PTF) of a sputter target by generating a magnetic field on a first side of the sputter target and passing the magnetic field through the sputter target and out a second side of the sputter target, measuring the magnetic field at the second side of the sputter target with a magnetic field detector, and moving one or both the sputter target or the magnetic field detector during the measuring using an automated stand. In various embodiments of the present invention, the automated apparatus and method may generate a map of the sputter target.

Abstract: A system and method for non-contact engine parameter sensing. A magnetized engine component establishes a magnetic field that varies in response to stress imparted within the engine. A magnetic field sensing element spaced from the magnetized engine component is configured to provide an output indicative of a state of combustion in response to the magnetic field.

Abstract: An electric current perturbation probe includes at least one driver coil and at least one receiver. The at least one driver coil produces an omni-directional magnetic field. The at least one receiver is decoupled from the omni-directional magnetic field. In one example, the at least one driver coil includes a first driver coil that defines a first effective coil axis which is positioned orthogonally to a second effective coil axis of a second driver coil. The first driver coil is provided with a first electrical excitation signal which is phase shifted by 90 degrees from a second electrical excitation signal used to drive the second driver coil.

Abstract: A system and method to detect changes in composite structures using RF signal pattern data interpretation. An RF signal is transmitted from a composite material manufactured structure and a plurality of sensors are employed to measure the RF signal. The measured RF signal is compared to a stored baseline RF signal for the particular structure. Deviations in the measured RF pattern for the structure, or for a structurally-similar composite structure, are automatically analyzed to detect non-visually-detectable defects or other changes in the composite structure. A baseline RF signature is developed for a structure by transmitting a reference RF signal from the composite structure. RF signals are detected by a variety of methods, and the detected signals are compiled and translated into reference and/or test RF signal patterns for the structure.

Abstract: A geo-storm generation apparatus includes a pair of coils disposed on a common center line with a predetermined interval, an electrode that is disposed between the pair of coils, an excitation power supply that excites the pair of coils such that magnetic fields with the same polarity are generated at facing ends of the pair of coils, and a control power supply that applies a control voltage to the electrode, wherein a geo-storm is generated between the pair of coils by concurrently driving the pair of coils with the excitation power supply.

Abstract: A rotating concave eddy current probe for detecting fatigue cracks hidden from view underneath the head of a raised head fastener, such as a buttonhead-type rivet, used to join together structural skins, such as aluminum aircraft skins. The probe has a recessed concave dimple in its bottom surface that closely conforms to the shape of the raised head. The concave dimple holds the probe in good alignment on top of the rivet while the probe is rotated around the rivet's centerline. One or more magnetic coils are rigidly embedded within the probe's cylindrical body, which is made of a non-conducting material. This design overcomes the inspection impediment associated with widely varying conductivity in fastened joints.

Abstract: A fuel cell diagnostic apparatus that diagnoses a fuel cell in which a plurality of power generating cells are stacked together includes a voltage applying device that applies voltage from outside of the fuel cell; a magnetic field measuring device that measures a magnetic field in or around the fuel cell when external voltage is being applied; and a diagnostic device that diagnoses the state of the fuel cell from the measurement results of the magnetic field. By diagnosing an in-plane distribution of current in the power generating cells by measuring the magnetic field, the distribution of water in an electrolyte membrane after power is generated can be diagnosed based on the diagnostic results of that in-plane distribution of the current.

Abstract: There is described a sensor comprising an excitation winding, a signal generator operable to generate an excitation signal and arranged to apply the generated excitation signal to the excitation winding, a sensor winding electromagnetically coupled to the excitation winding and a signal processor operable to process a periodic electric signal generated in the sensor winding when the excitation signal is applied to the excitation winding by the signal generator to determine a value of a sensed parameter. The excitation signal comprises a periodic carrier signal having a first frequency modulated by a periodic modulation signal having a second frequency, the first frequency being greater than the second frequency. In this way, the sensor is well suited to using digital processing techniques both to generate the excitation signal and to process the signal induced in the sensor windings. In an embodiment, the sensor is used to detect the relative position of two members.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter the high-field region of an MRI suite. The device comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: At least one measurement coil of an eddy current part inspection system is oriented relative to a track surface so that the longitudinal axis of the magnetic field generated by the at least one measurement coil is skewed relative to the track surface so as to be substantially aligned with the longitudinal axis of a part on the track surface which can move thereon through the at least one measurement coil.

Abstract: A material properties detection system (100). The system can include an antenna (120) that is tuned for operation within a frequency band over which the antenna transmits. The system also can include a transmitter (210) that generates electromagnetic energy across the frequency band and forwards the electromagnetic energy to the antenna. An impedance measurement circuit (215) can be provided. The impedance measurement circuit can measure an input impedance of the antenna over the frequency band and generate measured impedance data (225). The system can include a material characterization application (230) that processes the measured impedance data to generate a material characterization for a structure (110) to which the antenna is proximate. The material characterization can include a dielectric constant, a permittivity, a loss tangent and/or a permeability.

Abstract: A magnetic sensor device is used for detecting, e.g., a rotational speed of a rotor made of a magnetic material by sensing changes in a magnetic field. The magnetic sensor device is composed of a magnet, electronic components including a sensor chip and wiring for electrically connecting the electronic components. The wiring is formed on a surface of the magnet, and the electronic components are directly mounted on the wiring and electrically connected to the wiring. Alternatively, the electronic components are mounted on the magnet and electrically connected to the wiring via bonding wires. In this manner, a reed frame or a printed circuit board on which the electronic components are mounted can be eliminated to thereby reduce the number of parts used in the magnetic sensor device.

Abstract: A recording medium detecting system includes a magnetic field-generating unit that generates an alternating magnetic field in a predetermined particular region, a detecting unit provided close to the particular region, that detects a change in magnetic flux density not smaller than a predetermined magnetic-flux-density difference B2, and a recording medium, containing multiple magnetic wires made of a magnetic material and formed in a wire shape having a predetermined length, that causes a large Barkhausen effect when the alternating magnetic field is applied. A magnetic-flux-density difference B1 detected by the detecting unit at an installation position thereof when the recording medium is placed in the particular region is not smaller than the magnetic-flux-density difference B2.

Abstract: A ferromagnetic detection pillar having one or more applied magnetic field sources and one or more magnetic field sensors, with the magnets and sensors arranged and adapted to detect a ferromagnetic threat object on one side of the pillar. A detection device, such as a motion detector or infrared detector, is also provided, to detect the presence of an object on a selected side of the pillar. A single free-standing pillar can be used, or two or more free-standing pillars can be arranged to constitute a variable aperture detection portal. Single sensors or multiple-sensor configurations can be used.

Abstract: A method for detecting substructure includes the steps of: nondestructively scanning an assembly using a substructure scanning system including a precision motion carriage and a nondestructive scanning sensor, positioning the assembly under the substructure scanning system, positioning the scanning sensor on the outer skin, moving the scanning sensor over the outer skin with the precision motion carriage, locating the substructure through the outer skin, and controlling an assembly process using the location of the substructure. By using the method of the present invention substructure features may be located through an outer skin with sufficient accuracy to control assembly operations and to meet engineering tolerances. The method for precisely detecting substructure using precision eddy current scanning may be used for, but is not limited to, the location of substructure features, such as edges of flanges, machined steps, or tooling holes, covered by outer mold line skins of an aircraft airframe.

Abstract: Local features such as cracks in materials are nondestructively characterized by measuring a response with an electromagnetic sensor and converting this response into a selected property using a database. The database is generated prior to data acquisition by using a model to generate a baseline response or field distribution for the sensor and combining these results with another model, which may be simpler than the first model or provide a local representation of the field perturbations around a feature, which is evaluated multiple times over a range of values of the selected property. In addition, the presence of a feature may be detected by converting the sensor response into a reference parameter, such as a lift-off factor that reflects the sensor position relative to a material edge, and using this parameter to determine a reference response that can be compared to the measured response.

Abstract: A magnetometer is disclosed that enables high resolution magnetometry using magnetoresistive sensors that consume less power. The magnetometer exploits the ability of the sensor to alter or modulate sensitivity via external means. This modulation effectively transfers the signal of interest from the noisy DC domain to the AC domain by applying an AC signal to a current strap in a magnetic field sensor. The AC signal causes a first magnetic field to be formed in a direction perpendicular to the current strap. A magnetic field sensing structure in the magnetic field sensor senses the first magnetic field. The magnetic field sensing structure uses the first magnetic field to sense a second magnetic field. The second magnetic field is an external magnetic field that is of interest. An output of the magnetic field sensing structure is an AC signal that is proportional to the second magnetic field. The AC signal may be further amplified and refined employing signal conditioning techniques.

Abstract: A flexible elongate structure, such as a flexible riser (10), comprising at least one layer (20) of steel wires near the surface which extend at least partly along the length of the structure, can be monitored by inducing a small, alternating magnetic field in the steel wires using an electromagnetic coil, and monitoring the magnetic flux density near the surface of the structure so as to asses the stress and hence detect if any wires have broken. By using an array of stress-measuring electromagnetic probes (24) around the structure some spatial resolution can be provided as to the location of any break in the wires.

Abstract: A material analysis system configured to determine whether a circuit is defective includes a magnetic field generator configured to generate a first magnetic field that is configured to induce at least one eddy current in a conductive portion of the circuit, wherein the eddy current induces a second magnetic field; a set of magnetic field sensors configured to detect the second magnetic field and generate a set of image information therefrom; a database that includes circuit information for the circuit; and a computing device configured to receive the image information from the set of magnetic field sensors and retrieve the circuit information from the database, wherein the computing device is configured to compare the image information to the circuit information to determine whether the circuit is defective.

Abstract: A device for evaluating magnetic component performance and methods of evaluating transient magnetic performance of such components are disclosed. Magnetic flux capacity and/or energy loss of a magnetic component is/are measured, and the measurement data is electronically processed to evaluate the magnetic performance of the component.

Abstract: A device for testing a test specimen for surface faults is equipped for delivering a magnetic flux into the specimen and has induction probes measurement sensors. At least two yoke legs have opposed gap-forming ends with oppositely poled exciter coils between which the test specimen can be guided. Outside ends of the yoke legs opposite the gap-forming ends are connected to one another by a magnetic flux conductor so that the magnetic flux runs perpendicular to the lengthwise direction through the test specimen. To adapt to test specimens of different cross section, the yoke legs can be moved and fixed. Testing of test specimens by means of high-energy magnetic alternating fields improved because the high heat losses produced in this process are adequately dissipated. The device is especially well suited to determine the quality of bars, pipes and the like in a hot rolling mill with high-energy alternating magnetic fields.

Abstract: A method and an apparatus are disclosed, to screen patients or other areas for ferromagnetic objects, particularly for use intra-operatively in an operating room. The device comprises at least one magnetic field source, at least one magnetic gradiometer, and the associated electronics. The field source and the gradiometer are supported by an arm structure which can be manipulated to position the field source and the gradiometer at one or more positions near areas of interest, such as areas on a patient or other subject, and to orient the field source and the gradiometer so that the axis of the magnetic field is arranged along three different non-parallel, non-coplanar, axes to ensure detection of any ferromagnetic object regardless of its shape and orientation. The device can be manipulated to place the sensor arrays in close proximity to selected parts of a subject's body, for screening purposes.

Abstract: A method for fabricating and testing an article having a thermal-spray coating thereon. The method includes providing a substrate article having a surface, thermally spraying a coating material onto the surface of the substrate article, wherein a surface of contact between the coating material and the substrate article is a bondline, and nondestructively testing the coated article. Nondestructively testing includes generating an eddy current in the coated article, measuring the eddy current in the coated article, and evaluating a near-bondline region of the coated article located adjacent to the bondline using the measured eddy current.

Abstract: Autonomous non-destructive inspection equipment provides automatic and/or continuous inspection and evaluation of a material under inspection. The inspection equipment preferably comprises at least one detection sensor and at least one detection sensor interface for a computer. The autonomous non-destructive inspection system may also be retrofitted into conventional inspection systems by extracting pertinent features through spectral frequency analysis and sensor compensation and utilizing those features in the autonomous non-destructive inspection system.

Abstract: A magnetic material amount detecting apparatus includes primary winding and secondary winding which are wound on a core having a reading section to which a to-be-detected medium is set close. A current is supplied to the primary winding and an output signal from the primary winding is adjusted by an A.C. current detecting section. Then, a difference between the output signal output from the primary winding and adjusted by the A.C. current detecting section and an output signal from the secondary winding is output as a signal indicating the amount of magnetic material which is present near the reading section.

Abstract: A magnetic induction device mounted at the wellhead that is capable of measuring changes in magnetic flux can recognize when a tubing joint or casing collar passes in or out of the well. The number of changes in magnetic flux directly correlates to the number of joints and collars that have passed, and therefore an accurate inventory of the number of lengths of casing or tubing that are run into the well can be automatically maintained.

Abstract: There is described a sensor comprising an excitation winding, a signal generator operable to generate an excitation signal and arranged to apply the generated excitation signal to the excitation winding, a sensor winding electromagnetically coupled to the excitation winding and a signal processor operable to process a periodic electric signal generated in the sensor winding when the excitation signal is applied to the excitation winding by the signal generator to determine a value of a sensed parameter. The excitation signal comprises a periodic carrier signal having a first frequency modulated by a periodic modulation signal having a second frequency, the first frequency being greater than the second frequency. In this way, the sensor is well suited to using digital processing techniques both to generate the excitation signal and to process the signal induced in the sensor windings. In an embodiment, the sensor is used to detect the relative position of two members.

Abstract: A pair of cores are arranged such that first end portions thereof face to each other with a gap via a conveying path through which a medium to be detected passes. Coils wound at the first end portions of the cores, respectively, are connected in series to each other, thereby constituting a first coil. Coils wound at second end portions on a side opposite to the first end portions are connected in series to each other, thereby constituting a second coil. There are provided an exciting coil which generates a detection magnetic field passing the cores and the gap, and a convergent magnetic field generating unit which generates, in the gap, a convergent magnetic field for converging the detection magnetic field in a direction perpendicular to a direction in which the first end portions of the cores are connected to each other.

Abstract: There is described an inductive sensor for sensing a parameter such as position. The inductive sensor includes: receive aerial which is electro-magnetically coupled to a magnetic field generator via a resonant circuit with the electromagnetic coupling varying in dependence upon the sensed parameter so that a sense signal induced in the receive aerial is representative of the sensed parameter. The magnetic field generator generates a magnetic field including a first magnetic field component at a first frequency which is operable to induce resonance in the resonant circuit and a second magnetic field component at a second frequency which is not operable to induce resonance in the resonant circuit.

Abstract: A coil is operatively associated with a magnetic circuit of a vehicle body, and is adapted to cooperate with a time-varying magnetic flux in the vehicle body that is responsive to a condition of the vehicle body sensed by the magnetic sensor. An electrical circuit is operatively coupled to the coil, and the coil in cooperation therewith exhibits a resonant or near-resonant condition in association with the time-varying magnetic flux for at least one condition of the vehicle body. In one embodiment, a signal from an oscillator is applied to the series combination of a capacitor and the coil, which generates an oscillatory magnetic flux in the magnetic circuit. In another embodiment, a second capacitor is connected in parallel with a second coil which operates in a resonant or near-resonant condition responsive to the oscillatory magnetic flux in the magnetic circuit.

Abstract: The invention refers to a measurement probe for measuring magnetization data of at least one item (7), specifically a security document comprising at least one magnetic security material (M), said measurement probe comprising at least one core free magnetizing coil (3) characterized in that at least two magnetic field sensors (4s, 4c, 8s, 8c) are disposed at both ends inside said coil (3) at its both ends. The invention relates further to an authentication device comprising said measurement probe and to an authentication method carried out by means of said measurement probe and authentication device.

Abstract: A magnetic material detecting device which detects a magnetic material by applying a magnetic field to the magnetic material and detecting a magnetic field generated from the magnetic material by the applied magnetic field, and which includes a magnetizing coil which emits a magnetic field that excites the magnetic material, and a dummy coil which generates a magnetic field that excites the magnetic material by electromagnetic induction caused by the magnetic field emitted from the magnetizing coil, in which the dummy coil is disposed at a position where the electromagnetic induction is generated.

Abstract: A locator and marking apparatus comprises a housing and a surface on the housing for holding a magnet to be dispensed. Spacer members are formed on the housing such that the surface for holding the magnet is maintained a substantially predetermined distance from a substrate on which the locating and marking apparatus is positioned.

Abstract: Autonomous non-destructive inspection equipment provides automatic and/or continuous inspection and evaluation of a material under inspection. The inspection equipment comprises at least one detection sensor and at least one detection sensor interface for a computer. The signals are communicated from the sensor to the computer. The signals are then conditioned and evaluated according to knowledge already inputted into the computer. The computer iterations are processed until an acceptable conclusion is made regarding the type of imperfection that is detected.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a controlled area. The device comprises a screening portal, including multiple sensor arrays and associated electronics. The device places the sensor arrays in close proximity to a subject's body, including the head and feet if desired, for screening purposes. The portal can have multiple excitation sources oriented to generate a multi-axis excitation field, and multi-axis sensors. The portal can also have an interlock with the door of the controlled area.

Abstract: A test procedure and a metal detector having transmitting coils, receiving coils and an electronic processing circuit adapted to detect variations in the signals received by the receiving coils against a reference value. The metal detector, also includes a test module which has a selector able to detect a test request, and a controller, used when a test request is detected by the selector, able to compare the signals from the receiving coils during the subsequent passing of a known standard reference object with a predetermined response through the detector.

Abstract: A method for fabricating and testing an article having a thermal-spray coating thereon. The method includes providing a substrate article having a surface, thermally spraying a coating material onto the surface of the substrate article, wherein a surface of contact between the coating material and the substrate article is a bondline, and nondestructively testing the coated article. Nondestructively testing includes generating an eddy current in the coated article, measuring the eddy current in the coated article, and evaluating a near-bondline region of the coated article located adjacent to the bondline using the measured eddy current.

Abstract: In accordance with one embodiment of the invention, a method and system for detecting the position of a shaft comprises providing a shaft with defined hardened metallic regions. The shaft has a first hardened metallic region from a surface of the shaft to a first radial depth from the surface at a first longitudinal position. The shaft has a second hardened metallic region from the surface of the shaft to a second radial depth at a second longitudinal position. The second radial depth is different from the first radial depth. A sensor senses an eddy current to detect an alignment of at least one of the first hardened metallic region and the second hardened metallic region with a fixed sensing region at a respective time. A data processor determines a longitudinal position of the shaft with respect to a cylinder at the respective time based on the sensed eddy current.

Abstract: An eddy current monitoring system may include an elongated core. One or more coils may be coupled with the elongated core for producing an oscillating magnetic field that may couple with one or more conductive regions on a wafer. The core may be translated relative to the wafer to provide improved resolution while maintaining sufficient signal strength. An eddy current monitoring system may include a DC-coupled marginal oscillator for producing an oscillating magnetic field at a resonant frequency, where the resonant frequency may change as a result of changes to one or more conductive regions. Eddy current monitoring systems may be used to enable real-time profile control.

Abstract: Magnetic signature measurements are taken at various points corresponding to an original water depth beneath a ship. A computer processor receives and processes (i) this group of measured magnetic signature values and (ii) the designed magnetic signature value the sensing of which actuates the subject magnetic mine, implementing graph display management on a user interface display screen. According to the computer processing, some or all such measured magnetic signature values are extrapolated at different depths each greater than the original depth, thereby yielding several or many groups, each group being of extrapolated magnetic signature values associated with various points corresponding to the same depth, the groups collectively representing a three-dimensional arrangement of extrapolated magnetic signature values associated with various points corresponding to different depths.

Abstract: The present invention relates to a magnetoresistive sensing device, a system and a method for determining a density of magnetic particles in a fluid. The magnetoresistive sensing device has a substrate (1) with a layer structure (2) for supporting a fluid (3). The layer structure has a first surface area (4) in a first level and a second surface area (5) in another second level and a magnetoresistive element (6) for detecting the magnetic field of at least one magnetic particle (7) in the fluid, the magnetoresistive element being positioned near a transition (8) between the first and second surface area and facing at least one of the surface areas. A corresponding system and method is described as well.

Abstract: A method and apparatus to screen individuals specifically for paramagnetic or ferromagnetic objects they may be carrying or wearing, before they enter a security area. The device comprises either a screening portal or a compact, hand-held magnetic gradiometer and its electronics. The device places all of the sensor arrays in close proximity to all parts of a subject's body, for screening purposes.

Abstract: A device for detecting a prohibited object in a zone with protected access includes a supporting base designed to receive a single foot wearing a shoe of an individual to be inspected. The device further includes a detector to detect a target material and a position-identifier suitable for imposing accurate positioning of the foot of the individual being inspected relative to the detector.

Abstract: The device object of this patent is composed of:—one box (1) which is U-shaped in its transversal section;—two guiding plates (2) for the magnets (4);—two L-shaped rolled sections (3), which constitute the magnets (4) pole pieces;—various magnets (4) placed parallelly to the ferromagnetic insert (8) to be tested; each magnet (4) is placed parallel to the ferromagnetic insert (8) sliding direction with respect to the device and vice versa;—various measuring coils (5) placed in a housing (6), which is U-shaped in its transversal section;—a covering plate (7) fixed to box (1) in such a way to occupy the device side facing the insert (8) to be tested;—simple gears permitting to direct, in following times, the coils (5) parallelly to the different angles of the ferromagnetic insert (8) layers.