Abstract: A method for controlling actuation of label particles in a biosensor device, e.g., using frustrated total internal reflection, includes applying a predetermined actuation force on the label particles and determining the effect of the applied actuation force in a binding volume or surface of a sensor cartridge of the biosensor device. A feedback control of the actuation force is applied.

Abstract: A cooperative source electromagnetic induction (EMI) device includes: a transmitter configured to generate a time-varying primary magnetic field in the vicinity of a target object, which magnetic field inductively couples with the target object to generate a target object secondary magnetic field; and a cooperative source to which the primary magnetic field is also inductively coupled, generating one or more respective cooperative source secondary magnetic fields. The target object and the cooperative source are inductively coupled via the target object secondary magnetic field and the cooperative source secondary magnetic field. The device includes a receiver configured to measure a composite inductive response, which comprises the inductive coupling of the target object and the cooperative source.

Abstract: The device (18) for checking a tire (14) reinforcing thread comprises: an induction member (68, 70) that induces a magnetic flux (P1, P2; P) in the thread (42a-b; 100; 102), a support (67) supporting the induction member (68, 70) having the overall shape of a U and comprising legs (82, 84) that conduct the magnetic flux (P) into the thread (42a-b; 100; 102), the legs defining a direction of alignment of the device, at least one receiver member (74) that receives the magnetic flux (P1, P2; P) flowing through the thread (42a-b; 100; 102) situated between the legs (82, 84). The dimensions of the receiver member are designed so as to measure only the magnetic flux flowing through the thread (42a-b; 100; 102) when, in operation, the direction of alignment (18) is parallel to the thread (42a-b; 100; 102).

Abstract: A magnetic testing method and apparatus can accurately detect a flaw by magnetizing a test object to such a degree that the object becomes magnetically saturated while solving the problems of a large magnetizing device is required when only a DC magnetic field is applied and that the test object generates heat when only an AC magnetic field is applied. A magnetic testing apparatus comprises a first magnetizing device for applying a DC bias magnetic field to a test object P in substantially parallel to the direction in which a flaw F to be detected extends, a second magnetizing device for applying an AC magnetic field to the test object P substantially perpendicularly to the direction in which the flaw F to be detected extends, and a detecting device for detecting leakage flux produced by the magnetization of the test object P accomplished by the first and second magnetizing devices.

Abstract: An embodiment of a magnetic-field sensor includes a magnetic-field sensor arrangement and a magnetic body which has, for example, a non-convex cross-sectional area with regard to a cross-sectional plane running through the magnetic body, the magnetic body having an inhomogeneous magnetization.

Abstract: A detection system comprising a plurality of magnetic field generators and a plurality of magnetic field detectors located adjacent to a detection area, and a control system arranged to generate magnetic field using the generators, and, for each of the generators, to make measurements of the magnetic field generated using each of the detectors, and processing means arranged to process the measurements to generate a data set characterising the detection area.

Abstract: Magnetic material imaging (MMI) system including first and second sets of field-generating coils. Each of the field-generating coils of the first and second sets has an elongated segment that extends along an imaging axis of the medical imaging system. The imaging axis extends through a region-of-interest (ROI) of an object. The elongated segments of the first set of field-generating coils are positioned opposite the elongated segments of the second set of field-generating coils and the ROI is located between the first and second sets of field-generating coils. The MMI system also includes a coil-control module configured to control a flow of current through the first and second sets of field-generating coils to generate a selection field and to generate a drive field. The selection and drive fields combine to form a movable 1D field free region (FFR) that extends through the ROI.

Abstract: A method for quasi-static testing a magnetic recording head read sensor is described. The method includes applying a first voltage to a heater in the magnetic recording head and measuring an output of the magnetic recording head read sensor while applying the first voltage to the heater and recording the measured output as a first set of measurements. The method further includes applying a second voltage to the heater in the magnetic recording head and measuring the output of the magnetic recording head read sensor while applying the second voltage to the heater and recording the measured output as a second set of measurements. The first and second sets of measurements are then compared.

Abstract: A system and method for performing object localization based on the emission of electromagnetic fields. The electromagnetic fields are simultaneously emitted from different transmitters. One electromagnetic field is emitted at a base frequency; the remaining waves are emitted at frequencies that are harmonics of the base frequency. The composite magnetic fields are measured by sensors. The signal generated by each sensor is subject to a Fourier analysis to determine the strengths of the individual electromagnetic fields forming the composite electromagnetic field. These individual measure field strength data are then used to determine the position and orientation of the sensors relative to the transmitters.

Abstract: The ability to levitate and detect height and orientation of diamagnetic objects suspended in paramagnetic solutions using an inhomogeneous magnetic field is described. By comparing the measured height and orientation of a sample material with the measured height and orientation of a reference material, quality control of objects can be carried out. The major advantages of this quality control technique are: i) it is a simple apparatus that does not require electric power (a set of permanent magnets and gravity are sufficient for the diamagnetic separation and collection system to work); ii) it is compatible with simple optical detection; iii) it is a cost-effective and simple method that can carry out quality control between sample and reference materials rapidly.

Abstract: An eddy current sensor that includes: a probe and a computing unit. The probe has an exciting portion and a detecting portion. The exciting portion includes a first excitation coil that is wound around a non-magnetic bobbin so that a center axis direction is oriented in an x-axis direction and a second excitation coil that is wound around the non-magnetic bobbin to intersect with the first excitation coil so that a center axis direction is oriented in a y-axis direction. The detecting portion includes a detection coil that is arranged at the lower one of two intersecting portions of the first excitation coil and the second excitation coil. An eddy current measurement method for determining the thickness of a hardened layer.

Abstract: A magnetic inspection station for tubular members and methods for operating the same have a longitudinal flaw detection assembly adapted to pass a circumferential magnetic field through a tubular member and a transverse flaw detection assembly adapted to pass a longitudinal magnetic field through the tubular member. The magnetic fields cause congregation of a ferromagnetic particles sprayed on the tubular member in a magnetic particle inspection fluid. The congregation of ferromagnetic particles indicates a flaw in the tubular member. The magnetic inspection station includes a clamping apparatus positioned closely adjacent to the magnetic inspection station and adapted to support the tubular member within the magnetic inspection station and exert a compensating force on the tubular member to resist the magnetic forces generated by the longitudinal flaw detection assembly and the transverse flaw detection assembly.

Abstract: Provided is an eddy current inspection device, an eddy current inspection probe and an eddy current inspection method that make it possible to detect defects existing in deeper parts of test objects. Three or more odd number of excitation coils are arranged at even intervals in a circumferential direction on a postulated circumference. Excitation currents applied to the excitation coils are controlled so that the phase difference between excitation currents applied to adjacent ones of the excitation coils arranged in the circumferential direction on the postulated circumference equals one cycle divided by the number of excitation coils. A magnetic field generated according to an eddy current occurring in the test object due to a magnetic field caused by the application of the excitation currents to the excitation coils is detected by use of a detector arranged on a postulated plane containing the postulated circumference but inside the postulated circumference.

Abstract: A method and apparatus in which at least two different test phases are performed on a test object, selected from: conventional eddy current testing, partial saturation eddy current testing, and ultrasonic testing. Measurement data sets are obtained from the at least two different test phases, with each measurement data set comprising measurement data corresponding to a plurality of test positions. The data sets are combined in a data processing means and the combined measurement data is processed to evaluate a damage condition of the test object. In a preferred embodiment, all of conventional eddy current testing, partial saturation eddy current testing, and ultrasonic testing are performed. The apparatus may be provided in two or more sub-assemblies, of which one may be an internal test tool and one may be an external tool. Alternatively, the apparatus may be capable of carrying out all three of the test phases.

Abstract: A measuring apparatus for detecting a metal object includes two emission coils, a magnetoresistive measuring device, and a control device. The emission coils are configured to produce superimposed magnetic fields. The magnetoresistive measuring device is in the region of both magnetic fields, and is configured to emit an output signal which is dependent on the magnetic field. The control device is configured to supply the emission coils with alternating voltages such that the value of the alternating voltage component of the output signal, which is time synchronized with the alternating voltages, is minimized. The control device is further configured to detect the object when the ratio of the alternating voltages does not correspond to the distances between the magnetoresistive measuring device and the emission coils.

Abstract: A measuring device for detecting a metal object includes two emission coils configured to produce superimposed magnetic fields, a receiving coil in the region of both magnetic fields, and a control device configured to control the emission coils such that a value of a voltage, which is clock synchronized with alternating voltages and which is induced in the emission coils, is minimized. The control device is configured to detect the metal object when a ratio of the alternating voltages does not correspond to a ratio of distances between the receiving coils and the emission coils.

Abstract: A nondestructive evaluation apparatus and method for qualifying cold worked fastener holes. In an illustrative embodiment, the apparatus comprises a probe and a detector that interprets probe signals. An inductive sensor coil located in the probe uses a magnetic shielding arrangement to focus sensing to a specific zone of cold worked material around a hole in a test specimen. The shielding mitigates edge effects around the hole and measurement dilution away from the hole. A reference coil, located on not cold worked material away from the hole, provides a comparative baseline measurement. Sensor coils are arranged in a novel resonant filter bridge circuit in the probe and connected to the detector. The detector evaluates impedance changes on the probe caused electrical conductivity variations in the test specimen and correlates the changes to cold work quality.

Abstract: A measuring device configured to detect a metal object includes two emission coils configured to produce superimposed magnetic fields. The measuring device also includes a device configured to determine a differential voltage between the emission coils. The measuring device further includes a control device configured to supply the emission coils with alternating voltages such that the value of an AC voltage component of the differential voltage, which is time synchronized with the alternating voltage, is minimized. The control device is configured to detect the metal object when the ratio of the alternating voltages does not correspond to the ratio of the impedances of the emission coils when the metal object is not there.

Abstract: A system for monitoring the condition of a conveyor belt having magnetically permeable cords, has a magnetic field generator for generating a magnetic field to magnetize the cords, in use, a magnetic field sensing unit for sensing the magnetic field provided, in use, by the cords, the sensing unit comprising an array of spaced magnetic field sensors, the spacing of the sensors being sufficiently close to discriminate between adjacent cords. The spacing of the sensors depends on the spacing of the cords, and may be less than half the spacing between cords of a conveyor belt. The sensors may be direction sensitive and the sensors may be oriented in more than one direction, to sense the perpendicular and other components of the magnetic field.

Abstract: An apparatus for the nondestructive measurement of materials that includes at least two layers of electrical conductors. Within each layer, a meandering primary winding is used to create a magnetic field for interrogating a test material while sense elements or conducting loops within each meander provide a directional measurement of the test material condition. In successive layers extended portions of the meanders are rotated so that the sense elements provide material condition in different orientations without requiring movement of the test circuit or apparatus. Multidirectional permeability measurements are used to assess the stress or torque on a component. These measurements are combined in a manner that removes temperature effects and hysteresis on the property measurements. This can be accomplished through a correction factor that accounts for the temperature dependence.

Abstract: An eddy current sensor that includes: a probe and a computing unit. The probe has an exciting portion and a detecting portion. The exciting portion includes a first excitation coil that is wound around a non-magnetic bobbin so that a center axis direction is oriented in an x-axis direction and a second excitation coil that is wound around the non-magnetic bobbin to intersect with the first excitation coil so that a center axis direction is oriented in a y-axis direction. The detecting portion includes a detection coil that is arranged at the lower one of two intersecting portions of the first excitation coil and the second excitation coil. An eddy current measurement method for determining the thickness of a hardened layer.

Abstract: A segmented magnetostrictive patch array transducer capable of generating a high frequency shear wave in a structure such as a rod or a pipe, a structural fault diagnosing apparatus including the segmented magnetostrictive patch array transducer, and a method of operating the segmented magnetostrictive patch array transducer are shown. The segmented magnetostrictive patch array transducer includes a plurality of magnetostrictive patches attached along a circumference of a rod member; a plurality of insulators that are disposed on the magnetostrictive patches; a plurality of meander coils, each of the meander coils comprising a plurality of coil lines extending along the circumference direction of the rod member on each of the insulators, wherein a current flows through adjacent coil lines in opposite directions to one another; and a plurality of magnets that respectively form a magnetic field along the circumferential direction of the rod member on the magnetostrictive patches.

Abstract: A pipeline inspection tool includes two pole magnets oriented at an oblique angle relative to the central longitudinal axis of the tool body. An array of sensor coil sets is located between opposing edges of the two pole magnets and oriented perpendicular to the central longitudinal axis. Each sensor coil set includes a transmitter coil and two opposing pairs of receiver coils that are gated to receive reflections from the wall of a tubular member. Because the line of sensor coils is rotated relative to the magnetic bias field, the receiver coils are in-line with, and have the same angular orientation as, the transmitter coil. The tool provides improved sensitivity to small defects, substantial decrease in RF pulser power requirements, full circumferential coverage, self-calibration of the transmitted signals, and less interference between transmitter coils caused by acoustic ring around.

Abstract: A magnetic particle inspection (MPI) apparatus is disclosed that includes a chordal field coil pair and a radial field coil pair. The chordal field coil pair includes first and second chordal field coils configured to produce a chordally oriented magnetic flux about a test article.

Abstract: The invention concerns a method for producing an assembly of at least one transmission coil (B1) and one reception coil (B2) for eddy current testing, the reception coil receiving in the absence of fault a complex amplitude signal VR, subject to a variation ?VR in the presence of a characteristic fault to be detected. The method consists in selecting the distance ?ER between the axes of the transmission coil and the reception coil so as to maximize the ratio I?VR/VRI.

Abstract: A human-portable utility locator system for locating and tracing a buried utility line characterized by an electromagnetic field emission. The locator may include a horizontal spaced sensor pair for detecting the horizontal field asymmetry of the emitted field in one or more independent frequency bands, which is employed to assist in determining an accurate “virtual depth” measurement for producing detection events. An event detector may be disposed to detect events corresponding to extremum in the B-field gradient with respect to time and a user interface (UI) coupled to the event detector signals the detected event to a user. In a preferred embodiment, one pair of spaced-apart 3D magnetic sensor arrays is disposed substantially orthogonal to another intermediate spaced-apart pair of sensors.

Abstract: An apparatus for the nondestructive measurement of materials that includes at least two layers of electrical conductors. Within each layer, a meandering primary winding is used to create a magnetic field for interrogating a test material while sense elements or conducting loops within each meander provide a directional measurement of the test material condition in different orientations without requiring movement of the test circuit or apparatus. In a bidirectional implementation the meanders are oriented 90° apart while in a quadridirectional implementation the meanders are orientated at ?45, 0, 45, and 90°. Multidirectional permeability measurements are used to assess the stress or torque on a component. These measurements are combined in a manner that removes temperature effects and hysteresis on the property measurements. This can be accomplished through a correction factor that accounts for the temperature dependence.

Abstract: In one embodiment, a method for determining the distance of a conducting surface profiled in a direction of distance determination from a functional surface moving relative to the profiled surface is disclosed. The method includes connecting inputs of a sensor to an oscillator arrangement. The sensor includes a first and a second measuring coil. The method includes further connecting outputs of the sensor to an analog-to-digital converter via a demodulator unit to obtain first and second digital measured values. The first and second digital measured values correspond to the distance between the profiled surface and the first and second measuring coil of the sensor, respectively. The method further includes connecting an arithmetic unit to the analog converter unit. The second measurement coil is arranged at a known distance from the first measuring coil on the side of the first measuring coil that faces away from the profiled surface.

Abstract: An arrangement and method recognizes and classifies preferably hidden objects in object and/or human traffic. Objects relevant to security are recognized, located and tracked through the surroundings thereof in moving object and human traffic isolated in real time. Use is made of a combination of a field generator, the field of which is modified by at least one corresponding object within the scanned space, first sensors which repeatedly record the changes in the field and provide corresponding signals, second sensors which record defined surroundings of the object in real-time with relation to the first sensors and provide corresponding signals and analytical means which correlate and collate the signals from the sensors with each other and which give from the same the shape, spatial position and/or spatial orientation of the object.

Abstract: An eddy current testing device which confirms that a change in characteristics of a target object is detected regardless of the magnitude of the change and specifying the position of a portion from which the change is detected. The device uses an eddy current probe to inspect a bent portion of a metal body, and has an inspection controller and a display unit. The inspection controller calculates a phase angle of a signal detected by the eddy current probe and generates flaw identification image data that indicates an area (or an area of the signal detected and determined to correspond to a flaw signal, based on the phase angle of the detected signal) of a flaw signal in coordinates in which the position of the portion of the target object is plotted along a coordinate axis. The display unit displays the flaw identification image data.

Abstract: The invention relates to a method and arrangement for the contactless determination of conductivity-influencing properties and their spatial distribution over the entire cross section of an electrically conductive substance moving in a primary magnetic field (B). The substance may be a liquid or a solid. A simultaneous measurement of a number of mechanical state parameters of the magnetic system is performed (three-dimensional components of the force and the torque), said parameters being variable by the effect of a secondary field on the magnetic system, the secondary field being produced on the basis of eddy currents induced in the substance by the primary field (B). To determine the spatial distribution of the property that is sought, the primary field is changed in intensity or form a number of times and a measurement of the state parameters is carried out for each change.

Abstract: The invention relates to a device for measuring the mass of a magnetic material (6) present in an analysis medium, that comprises: a modulator (24) of the phase of a high-frequency and/or low-frequency component of a magnetic field for exciting the analysis medium with a modulation signal having a value that is modified by a frequency fmod; and a demodulator (36) capable of demodulating the amplitude of an amplitude signal, measured in response to the excitation field, from the modulation signal, wherein said demodulator is connected to the output of a filter (34) and to the input of an estimation unit (44).

Abstract: A method for detecting metal in an inner region of a caster mould during a casting process using a plurality of eddy current probe assemblies, wherein each of the plurality of eddy current probe assemblies is configured to generate a primary magnetic field passing through nonconductive mould material of the casting mould to the inner region of the casting mould and to provide a signal indicative of a detected secondary magnetic field caused by eddy currents induced in the metal.

Abstract: Disclosed is a method and an NDT/NDI probe deploying a slit or a flexible joint of probe bending region, preferably between two rows of probe elements to allow free bending between rows of probe elements and along the direction of the rows of elements and to allow two adjacent rows of elements to bend individually along its own natural bending lines perpendicular to the direction of the rows of elements. Also disclosed is the use of protective flexible pads to cover the probe elements and other probe components.

Abstract: A method for inspecting a component having a surface profile that includes a local minima and a local maxima. The method includes positioning an eddy current probe proximate to a surface of the component to generate a first position indication, positioning the eddy current probe proximate to the surface of the component to generate a second position indication that is different than the first position indication, and interpolating between the first and second position indications to determine a profile of a portion of the surface of the component.

Abstract: A flexible elongate structure, such as a flexible riser (10) for connecting oil and gas wells to floating production platforms, 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 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 detect if any wires have broken. Measurements are made at two different frequencies, the lower frequency giving an output dependent both on stresses and on the number of adjacent wires in the layer (20), and the higher frequency giving an output primarily dependent on the number of these wires. By comparing these two measurements a corrected output parameter (P) may be obtained that is indicative only of stress. A break in a wire can be expected to change the stress in that and adjacent wires.

Abstract: An information reading device for reading identification information from a medium to which at least one magnetic element for generating a signal upon receiving a magnetic field is provided, which includes a plurality of detecting parts that detect a signal generated from the magnetic element according to the magnetic field applied to the medium, and an information reading part that reads information formed by the magnetic element based on a combination of detecting parts which have detected the generated signal.

Abstract: The invention relates to a switch acting in contactless fashion for the purpose of detecting the position of a first part with respect to a second part, having a transceiver for attachment to one of the parts, which transceiver is supplied with power by an electrical supply source and comprises a coil, which is connected to a transmission/reception circuit, for the purpose of transmitting an interrogation signal and for the purpose of receiving a response signal, which can be transmitted in response to the interrogation signal by a transponder which can be arranged on the other part, wherein in addition to a first path for processing the response signal to an evaluation circuit, a second path is provided which has a proximity circuit, which is connected on the input side to a connection of the coil and on the output side to the evaluation circuit for the amplitude of the voltage tapped off by the coil for the purpose of determining the distance between the parts.

Abstract: The invention relates to a method for securely monitoring a distance between a metallic part and an inductive proximity sensor, in particular for monitoring a closed position of a guard door in an automated system, said method having the steps of: providing an oscillating circuit, providing a metallic part made of a first material, driving the oscillating circuit with at least one pulse, such that a decaying oscillation is generated which is dependent on a distance between the metallic part and the oscillating circuit and which has an actual frequency and an actual attenuation, and signaling whether both the actual frequency undershoots a predefined maximum frequency and the actual attenuation undershoots a predefined maximum attenuation. The invention also relates to a signaling device for monitoring a distance between a metallic part and an inductive proximity sensor.

Abstract: The invention relates to a microelectronic sensor device for manipulating a sample in an exchangeable carrier (111), for example for optically detecting target particles (1) in a sample liquid that is provided in a sample chamber (2) of the carrier (111). The microelectronic sensor device comprises a number of n>1 magnetic field generators (141-143), e.g. electromagnetic coils, with which magnetic fields can be generated in a target region (110). A control unit (150) is provided that can determine and evaluate the mutual coupling or the self-inductance of the magnetic field generators and/or signals from magnetic field sensors attached to the carrier with respect to the presence and/or state of a carrier (111) in the target region (110). In this way, the control unit (150) can for example detect if the carrier (111) is correctly positioned in the sensor device and/or where a magnetically interactive substance (1, 120) is located.

Abstract: A system for use when measuring a magnetostriction value of a magnetoresistive element according to one embodiment includes a mechanism for applying a first magnetic field about parallel to a substrate having one or more magnetoresistive elements, and for applying a second magnetic field about perpendicular to the substrate and about parallel to magnetoresistive layers of the elements; and a mechanism for applying a mechanical stress to the substrate during application of the magnetic fields.

Abstract: The present invention pertains to a method for the nondestructive testing of pipes made of ferromagnetic steel by means of a stray flux, in which the pipe, which is moving in the longitudinal direction and alternatively additionally rotating, is magnetized by a constant field, and the generated magnetic flux is transmitted into the pipe in a contactless manner, and the flaws that are located in the near-surface area of the outer or inner surface of the pipe bring about magnetic stray fluxes, which emerge from the pipe surface and are detected by means of sensors. The amplitudes, preferably of the horizontal field component of the magnetic stray flux, which vary in the vertical direction, are detected, on the one hand, at a near-surface distance from the pipe outer surface, and, on the other hand, at a distance lying further remotely therefrom, and the detected signals are related to one another.

Abstract: A method for non-contact determination of sought properties of an object to be measured by using electromagnetic induction. An electromagnetic field is generated in a transmitter coil placed on one side of the object to be measured. The magnetic field penetrates through the object to be measured and is detected by a receiver coil placed on the other side of the object to be measured. A control coil is placed near the transmitter coil generating a change in the magnetic field of the transmitter coil. A field change in the detecting is detected in the control coil. The field is detected in the receiver coil. The difference in time is determined for the detection of the field change in the control coil and in the receiver coil, respectively. The time of penetration through the object to be measured is determined, and the thickness or electrical conductivity of the object to be measured is determined therefrom.

Abstract: A CAM (current arrow map) 71 and another CAM 72 are obtained from magnetocardiogram waveforms measured from both front and back sides of a subject using data at a point of time of an R-wave peak, then the coordinates of the CAM 72 are inverted in both x and y axis directions to obtain a CAM 73. The coordinates of each of the CAMs 71 and 73 are converted to polar coordinates to obtain CAMs 74 and 75 at both front and back sides of the subject. After that, the CAM 74 is adjusted to the CAM 76 in scale to obtain a CAM 76 , and CAMs 74 and 76 are combined. Then, the CAM data at measuring points on each measuring-points-missing radius vector is inserted through an arithmetic processing by interpolation so that CAM data at every measuring point on a planispheric chart 77 are connected to each another consecutively.

Abstract: A system for sorting fine nonferrous metals and insulated copper wire from a batch of mixed fine nonferrous metals and insulated wire includes an array of inductive proximity detectors, a processing computer and a sorting mechanism. The inductive proximity detectors identify the location of the fine nonferrous metals and insulated copper wire. The processing computer instructs the sorting mechanism to place the fine nonferrous metals and insulated copper wire into a separate container than the non-metallic pieces.

Abstract: A toroidal power transformer is disclosed. The toroidal power transformer comprises a circular core composed of plurality of laminated electrically conductive materials, a plurality of multi-layered first windings radially wound around the circular core, said winding arranged with an angular spacing of 2? and a number of windings in each winding layer is less than a number of windings in each previous layer, a multi-layered second winding radially wound around the circular core covering a corresponding one of said plurality of first windings, wherein the layers of each of said second windings are arranged to form a substantially triangular cross-section; and an insulating layer between each of said first and second windings.

Abstract: The present invention relates to systems and methods for magnetic actuation of particles from and toward the surface of a sensor with a magneto-resistive element. The orientation of magnetic fields and arrangement of magnetic field generating means with respect to the sensor maintains or restores the sensitivity of the magneto-resistive element after actuation.

Abstract: An RFEC excitation unit and sensor apparatus and method that facilitate detection of cracks or other anomalies within or under a surface and immediately next to an expected structure (such as a rivet) that would otherwise cause a signal change preventing detection of the cracks. In some embodiments, the apparatus includes actuators and control that move the apparatus and analyze sensed RFEC signals to determine the location of the rivet, and then to rotate (mechanically or electronically) the sensed signal and/or excitation signal to maintain a constant relationship to the edge of the rivet in order that signals from the rivet edge are suppressed and signals from the cracks are detected. In some embodiments, the excitation unit is maintained at the center of the rivet surface, and the sensor is moved around the rivet in a circle centered on the rivet.

Abstract: A metal detector for control of protected access comprises two oblong shape vertical housings (10, 12), a structure (14) connecting the upper part of the vertical housings (10, 12) and emitting and receiving electrical coils (3, 5) provided in the housings (10, 12). Each of the two housings (10, 12) comprises two separate emitting (3) and/or receiving (5) coils. The coils operate so that each of the two housings (10, 12) comprises one emitting coil (TX) and one receiving coil (RX). The metal detector further comprises a controller for controlling operation of the emitting and receiving coils, so that when an emitting coil (TX1, TX2) provided in a housing (10, 12) is active, the two receiving coils (RX1, RX2) provided respectively in both the two housings are also simultaneously or subsequently active.

Abstract: An inspection method and an inspection apparatus that can easily measure a distribution of residual stress on a surface processed by shot peening, including a state of distribution in a depth direction of a material to be treated in a relatively short time without destroying the material to be treated. A coil provided in the inspection circuit is arranged on a surface processed by shot peening of the inspection target, an alternating current signal is input to the inspection circuit with changing a frequency so that frequency response characteristics of impedance of the inspection circuit is measured and acquired as inspection target data, and the inspection target data is compared to frequency response characteristics of impedance acquired from a sample of which a state of generation of residual stress is found.