Abstract: A magnetic sensor unit includes a magnet, a magnetic sensor facing a lower surface of the magnet, a magnetic shield surrounding the magnetic sensor in a lateral direction crossing up and down directions of the magnetic sensor, and a magnetic yoke covering an upper surface and a side surface of the magnet. The magnet includes a first magnetized region magnetized along the up and down direction, and a second magnetized region magnetized in a direction opposite to a direction of magnetization of the first magnetized region. The first and second magnetized regions have first and second magnetic poles provided on the lower surface of the magnet. A distance LA between a center of the first magnetic pole and a center of the second magnetic pole, a distance LB between the magnetic shield and the center of the first magnetic pole, a distance LC between the magnetic shield and the center of the second magnetic pole satisfy a relation of LA<LB+LC.

Abstract: Apparatus and associated methods relate to monitoring health of a system for sensing rotational frequency of a rotatable member. A plurality of magnetic speed probes, each of which is configured to sense the rotational frequency of the rotatable member, are arranged in transmissive proximity with one another. A transmitter-configured one of the plurality of magnetic speed probes includes a signal coupler that couples an electrical signal generated by a radio-frequency signal generator into the inductive coil of the transmitter-configured magnetic speed probe, thereby radiatively transmitting an electromagnetic signal. A speed-probe monitor electrically coupled to each of the plurality of magnetic speed probes determines, based on the coil current sensed by each of the plurality of magnetic speed probes in response to the electromagnetic signal radiatively transmitted, health of the system.

Abstract: Systems and methods interacting with tabletop models using a handheld device are provided herein. A display system includes a tabletop model, including a horizontal display that is configured to display a two-dimensional digital map and a three-dimensional physical model that is configured to overlay the two-dimensional digital map. The display system includes a mobile device including a touchscreen display. The display system transforms a movement on the touchscreen display to a movement of a cursor on the two-dimensional digital map.

Abstract: A rotation sensing apparatus includes a detected part, a sensor unit, and a rotation information calculation circuit. The sensor unit includes a first sensor disposed opposite to a first pattern portion, a second sensor disposed opposite to a second pattern portion, a third sensor disposed to be spaced apart from the first sensor in the rotation direction and opposite to the first pattern portion, and a fourth sensor disposed to be spaced apart from the second sensor in the rotation direction and opposite to the second pattern portion. The rotation information calculation circuit is configured to sense the rotation direction, in response to a differential signal, generated based on the first oscillation signal and the second oscillation signal, and an oscillation signal corresponding to maximum and minimum frequencies, from among the first oscillation signal, the second oscillation signal, the third oscillation signal, and the fourth oscillation signal.

Abstract: The semiconductor device controls the first circuit for supplying/stopping the current supplied by a DC power supply to the latching solenoid consisting of a coil and a movable iron core and a permanent magnet, the current is measured based on the input from the current detection circuit. The semiconductor device includes a control circuit having a low power dissipation mode in which the leakage current is reduced, and a normal operation mode. The control circuit maintains the low power consumption mode when no current is flowing through the coil, when a current is flowing through the coil maintains the normal operation mode, further, the movable iron core It comprises a control circuit configured to detect the inflection point of the current detected by the current detection circuit when leaving the permanent magnet.

Abstract: A distance measuring device (100) is provided, comprising a first sensing module (110), a second sensing module (120), a reference device (130), and an evaluating module (140). The first sensing module and the second sensing module are arranged on a horizontal base line (150). Each one of the first and second sensing module is configured to detect the strength of a magnetic field (50) and each one of the first and second sensing module has a first sensing direction (y) and a second sensing direction (x).

Abstract: A method for measuring a non-magnetic coating thickness upon a non-magnetic gas turbine component, such as a hot gas path component, can comprise applying a magnetic coating, such as a ferrous coating, upon the non-magnetic gas turbine component, applying a non-magnetic coating, such as a metallic bond coating, upon the magnetic coating, and measuring a thickness of the non-magnetic coating with a magnetic induction probe. The magnetic induction probe can be calibrated to the magnetic coating before the non-magnetic coating is applied. Measuring of the thickness of the non-magnetic coating can be used to validate spray patterns of automated spray processes. The magnetic and non-magnetic coatings can be stripped from the gas turbine component and used to validate additional spray patterns.

Abstract: Apparatuses, systems, and associated methods of assembly are described that provide for improved sensor devices. An example sensor device includes a bobbin tube that defines a hollow interior. The device includes a primary coil element wound around the bobbin tube configured to, in response to a current input, generate a primary magnetic flux and includes a secondary coil element wound around the primary coil element. In an instance in which the bobbin tube receives a probe assembly therein, magnetic interaction between the probe assembly and the primary coil element is configured to induce a signal in the secondary coil element. Furthermore, a pitch of the secondary coil element varies according to a non-linear, polynomial function along a second length of the bobbin tube so as to reduce linearity error of the sensor device.

Abstract: An electromagnetic device is disclosed, the electromagnetic device comprising a core support having an exterior surface comprising at least one radial protrusion, a tubular magnetic core positioned around a portion of the length of the core support, the tubular magnetic core having an interior surface, at least one indent located in the interior surface of the tubular magnetic core, wherein the at least one protrusion is located within the at least one indent to prevent relative longitudinal movement between the core support and tubular magnetic core, and a primary coil and at least one secondary coil, each coil positioned around a portion of a length of the tubular magnetic core.

Abstract: The present invention provides a rotation angle detector capable of detecting a rotation angle of a rotor in the same manner as at normal time even when abnormality such as disconnection or a short circuit occurs, and capable of reducing the number of terminals. When one spatial order cycle of the output winding is an electrical angle of 360°, a phase difference between a first output winding and a second output winding and a phase difference between the second output winding and a third output winding are set at an electrical angle ?, and ??180°×n (n is an integer).

Abstract: A distance measuring device (100) is provided, comprising a first sensing module (110), a second sensing module (120), a reference device (130), and an evaluating module (140). The first sensing module and the second sensing module are arranged on a horizontal base line (150). Each one of the first and second sensing module is configured to detect the strength of a magnetic field (50) and each one of the first and second sensing module has a first sensing direction (y) and a second sensing direction (x).

Abstract: Embodiments generally relate to assembly and methods for precisely rigging a linear variable differential transformer (LVDT). For example, the probe rod assembly of a dual tandem LVDT may comprise two moveable cores, a probe fitting, and a probe rod. Generally, the first moveable core may be configured to achieve electrical zero with its respective transformer. Without adjusting the position of the probe rod with respect to the one or more coils of wire, the second moveable core may be configured to achieve electrical zero with its respective transformer. This may ensure that both moveable cores simultaneously achieve electrical zero in the null position. Typically, the probe fitting may be configured to fit at a first end of the probe rod projecting outward from the outer housing. The disclosed assembly and methods may be used to precisely rig dual tandem LVDTs, single channel LVDTs, and dual parallel LVDTs.

Abstract: The sensor for detecting the position of a generator element which outputs a position-dependent physical variable, the sensor includes a transducer for converting the physical variable into an electric generator signal, a circuit on a wiring support for receiving the generator signal from the transducer and outputting a measurement signal that corresponds to the generator signal and a protective compound which at least partially surrounds the transducer and the wiring support, thus retaining the transducer on the wiring support.

Abstract: A central point positioning determination device and a central point positioning method thereof for a rotor coil of a large-scale steam turbine generator includes a control device, a pulse acquisition device, and a pulse generation device. The pulse generation device is connected to connection ends of a positive terminal and a negative terminal of the rotor of the generator, and a rotor body of the rotor. The control device controls the pulse generation device to send pulses to the positive terminal, the negative terminal, and the rotor body of the rotor of the generator. By doing so, the central point of the rotor coil can be found conveniently and quickly.

Abstract: A system for determining the location of a movable element within a container is provided in which a linear variable differential transformer (“LVDT”) is formed with the container and the movable element therein. The LVDT includes a coil assembly including a primary or excitation winding, a secondary or output winding, and a movable element or core that is magnetically permeable. Measurement of an output signals allows for precise determination of the movable element location relative to the container. The system can be utilized to determine fluid volumes in accumulators used for controlling subsea equipment by monitoring the location of a movable element, e.g., a piston, within a hydraulic fluid accumulator.

Abstract: A system for detecting a position of an object includes a position sensor and a demodulator. The position sensor receives a first excitation signal, senses a displacement of the object with respect to a reference point based on the first excitation signal, and generates first and second sense signals based on the first excitation signal. The demodulator receives the first sense signal and the second sense signal from the position sensor, performs a first cross-correlation calculation between the first sense signal and a second excitation signal and a second cross-correlation calculation between the second sense signal and the second excitation signal, determines displacement of the object with respect to the reference point based on results of the first and second cross-correlation calculations, and determine a position of the object based on the displacement.

Abstract: A single housing with a non-ferromagnetic piezo-driven flexure has primary and secondary coil forms of different diameters, one coaxially inside the other, integrated in the flexure. The cylinders defining the planes of the primary and secondaries do not spatially overlap. The secondary coil forms may be wound in opposite directions and wired to provide a transformer device. Movement of the primary relative to the secondaries in the direction of the central axis of the coils can be differentially detected with high precision.

Abstract: A tool for evaluating the internal surfaces of tubular is provided, wherein one or more arms extend outwardly from the tool into contact with an inner wall of the tubular, and changes in the dimensions or condition of the inner wall result in changes in the position of the ends of the arms relative to the tool. This motion is converted, through an electromagnetic transducer, into an electrical signal, the amplitude of which falls is maintained as the temperature of the tool changes. In one aspect, the transducer includes a coil and a moveable metal or magnetic element. The coil is powered by a constant current source, and variations in the resistance of the electrical components of the transducer resultingly do not cause fall off of the output signal amplitude.

Abstract: A current-to-voltage conversion circuit according to one aspect of the present invention includes a first resistor, a first current source, a first capacitor, a first output terminal, a first voltage source, a first transistor, and a second resistor. The first resistor includes a first end and a second end. The first end of the first resistor is connectable to an electrode included in a sensor and the second end of the first resistor is connected to a first electrical potential. The first capacitor includes a first end and a second end. The first end of the first capacitor is connected to the first end of the first resistor and the second end of the first capacitor is connected to the first current source. The first transistor includes a first terminal, a second terminal, and a control terminal. The first terminal is connected to the second end of the first capacitor, the second terminal is connected to the first output terminal, and the control terminal is connected to the first voltage source.

Abstract: A rotational resolver system and method includes a rotational shaft to which at least one eccentric conductive coarse resolution disc is fixed and to which at least one conductive fine resolution disc is also fixed. The fine resolution disc defines a plurality of generally semicircular protruding edge segments. At least one conductive coarse-disc sensing coil is disposed adjacent an edge of the coarse resolution disc, and at least one conductive fine-disc sensing coil is disposed adjacent the edge of the fine resolution disc. These coils may be oriented for axial sensing of the respective disc.

Abstract: A method for determining a reference current curve for a fuel injector having a magnetic coil drive in an internal combustion engine of a motor vehicle includes: (a) applying a first voltage pulse to the magnetic coil drive to open the fuel injector, (b) applying a holding voltage to the magnetic coil drive to hold the fuel injector open, (c) switching off the holding voltage, (d) waiting for substantially no current to flow through the magnetic coil drive for a predetermined time period that is sufficiently short that the fuel injector remains open, (e) applying a second voltage pulse to the magnetic coil drive, and (f) recording a time-based curve of the current that flows through the magnetic coil drive during the second voltage pulse, which forms the reference current curve. This reference current curve is used for determining a time of a predetermined opening state of the fuel injector.

Abstract: A position measurement system including a material measure and a scanning device movable relative to one another with respect to a measurement direction. The material measure has a plurality of markings which are arranged in a row with respect to the measurement direction, wherein the scanning device includes a transmitter winding arrangement. Multiple receiver coils are provided which are arranged in a row with respect to the measurement direction. The inductive coupling between the transmitter winding arrangement and the receiver coils is a function of the position of the scanning device with respect to the material measure. The transmitter winding arrangement defines multiple separate transmitter areas which are arranged in a row with respect to the measurement direction. A maximum of one single receiver coil is situated in each of the transmitter areas. At least one switching means is provided via which the two adjacent receiver coils are differentially interconnectable.

Abstract: A scanning head for scanning a material measure on which markings with a period are formed periodically in the measuring direction includes at least two individual sensors configured to produce sensor signals by scanning the markings. The scanning head further includes a digital signal processing apparatus configured to produce at least one highly accurate output signal from the sensor signals. The scanning head is configured to output at least two different types of output signals. The at least two different types of output signals comprises at least one safe output signal and the at least one highly accurate output signal.

Abstract: An apparatus for operating a resolver which includes at least one first receiver winding and an exciter winding, which are/can be associated with a rotor, and an evaluation device which determines an angular position of the rotor as a function of an induced voltage that is generated by the exciter winding and detected by the receiver winding. According to the invention, the first receiver winding is connected at a first end to an actuable switch by means of a first RC circuit, said switch connecting the RC circuit as required to a positive voltage source, and the first receiver winding is connected at a second end to a second actuable switch by means of a second RC circuit, said second switch connecting the second RC circuit as required to a negative voltage source, and to a control unit which simultaneously actuates the switches as required.

Abstract: A sensor for detecting a position of an encoder magnet in a direction of motion, including: a first coil extending in the direction of motion, a second and third coil, which are aligned with the first coil and which are arranged symmetrical to each other with respect to a point of symmetry as observed in the direction of motion and which accordingly form a first and second transformer with the first coil, the transformation ratio of which transformers depends on the position of the encoder magnet, and a magnetic asymmetry, which changes the transformation ratio of one of the transformers with respect to the other transformer.

Abstract: A method for determining a position of a magnet assembly relative to an array of inductive elements arranged adjacent to a magnetically permeable material, the method involving: measuring electrical characteristics of each of one or more inductive elements of the array of inductive elements; and from information derived from the measured electrical characteristics of the one or more inductive elements of the array of inductive elements, determining the position of the magnet assembly relative to the array of inductive elements.

Abstract: A sensor for detecting a position of a transducer magnet in a movement direction, including: —a coil carrier extending in the movement direction, —a first coil extending in the movement direction that is wound onto the coil carrier and—a second and a third coil oriented according to the first coil, which are wound onto the coil carrier such that the second and third coils accordingly form a first and second transformer with the first coil, the transformation ratio of which is dependent on the position of the transducer magnet, —wherein at least the second coil or the third coil is arranged between the coil carrier and the first coil.

Abstract: Sensor having a primary coil, two secondary coils as well as an evaluator. An excitation signal may be applied to the primary coil. An output signal depending on a position of a coupling element may be induced in each secondary coil. An evaluator is configured to evaluate the output signals in order to evaluate a phase offset between the output signals. Further, the evaluator is configured to provide a sensor output signal indicating the position or change in position of the coupling element.

Abstract: A single housing with a non-ferromagnetic piezo-driven flexure has primary and secondary coil forms of different diameters, one coaxially inside the other, integrated in the flexure. The cylinders defining the planes of the primary and secondaries do not spatially overlap. The secondary coil forms may be wound in opposite directions and wired to provide a transformer device. Movement of the primary relative to the secondaries in the direction of the central axis of the coils can be differentially detected with high precision.

Abstract: A device for focusing a laser in which a voice coil and LVDT are mounted in parallel alignment with each other and have a common centrally disposed armature. A central bore extends through the armature. A lens is mounted at one end of the armature and a laser is located at the opposite end. The laser beam passes through the central bore and is focused by the voice coil moving the armature which in turn moves the lens. The LVDT accurately positions the armature to focus the laser beam.

Abstract: An apparatus includes a housing which defines a longitudinal axis; a positioning element which, relative to the housing, translates linearly along the longitudinal axis; and a rotational member which, relative to the housing, rotates about the longitudinal axis as the positioning element translates linearly along the longitudinal axis. The rotational member defines a helix to receive torque from the positioning element as the positioning element translates linearly along the longitudinal axis. The apparatus further includes a first sensor assembly to detect minor angular displacement of the rotational member (e.g., less than 360 degrees). The apparatus further includes a second sensor assembly to detect major angular displacement of the rotational member (e.g., a number of full 360 degree rotations). Such detection is capable of identifying a full angular displacement of the rotational member in response to linear translation of the positioning element from an initial position to a sensed position.

Abstract: Electrodynamic control of fluid leakage loss is provided. Embodiments utilize electrohydrodynamic (EHD) principles to control and/or reduce leakage flow in turbomachinery. Electrodes can be used to provide a flow actuation mechanism inside the clearance gap for generating discharge. The electrodes can be positioned to have geometric asymmetry. Embodiments provide the electrodes on a turbine blade. The blade can have a DC power that can function as a square pulsed DC wave with the duty cycle equal to the blade passing frequency and the stator can be grounded. In an embodiment, the stator can have the actuator of the electrode-insulator assembly attached to the inside. In one embodiment, the actuators can be arranged just on the stator or casing. The phase and power supply to individual electrodes can be adapted as needed. In one embodiment, the phase can be lagged for accurate control of leakage flow.

Abstract: Circuit for evaluating resolver sensor signals (28) in a vehicle, having a resolver sensor (4), set up to pick up a rotary movement of a rotor (6) in an electrical machine (16), and a processor element (12), wherein the resolver sensor (4) is set up to output at least one sinusoidal or cosinusoidal amplitude-modulated analog signal that is characteristic of the rotary movement of the rotor (6), characterized in that the processor element (12) has a data processing unit (12a), a resolver sensor actuation unit (12b) and a resolver sensor evaluation unit (12c), wherein the analog signal from the resolver sensor (4) is connected directly to the resolver sensor evaluation unit (12c).

Abstract: Displacement sensor arrangement including at least one primary coil, at least a first and a second secondary coil and at least one magnetically soft coupling element, which magnetically couples the primary coil and the two secondary coils, the displacement sensor being designed so that a position and/or deflection depending on the magnetic coupling between the primary coil and at least the first and second secondary coil is detected, the displacement sensor arrangement having a signal processing unit, which is designed to perform digital signal processing of at least one electrical variable of the two secondary coils and determine the position and/or deflection, the signal processing unit having at least one Goertzel filter.

Abstract: The invention relates to a shielded double-coil multilayer assembly intended to be used in an inductive detector. This multilayer assembly comprises a plurality of stacked parallel separated layers, namely: a layer (C1) comprising a first shielding element for a first coil, a layer (C2) comprising all or part of a first coil, a layer (C3) comprising all or part of a second coil, a layer (C4) comprising a first shielding element for the second coil.

Abstract: A low power inductive proximity sensing system in which a DC voltage to the inductors is only applied for a short time period needed to detect the presence or absence of an appropriate object. After the detection time period is over, DC voltage is no longer applied to the inductors.

Abstract: A position sensor includes a detector, an oscillation circuit, a signal processing circuit, and a resonance circuit having a detection coil and a capacitor. The oscillation circuit forms a negative feedback loop from: an amplitude detection circuit that detects an amplitude of an oscillation signal outputted from the resonance circuit; an integrating circuit that outputs a signal corresponding to a difference between a predetermined reference voltage and the amplitude of the oscillation signal; a negative conductance control circuit that, based on the output of the integrating circuit, controls the negative conductance of the oscillation circuit such that the amplitude of the oscillation signal is equals to the predetermined reference voltage; and an operational amplifier that adjusts such that the oscillation voltage of the resonance circuit is equal to the applied voltage of the negative conductance control circuit.

Abstract: One embodiment of the present invention relates to a method and apparatus to perform a low power activation of a system by measuring the slope of a digital signal corresponding to a motion sensor measurement value. In one embodiment, a low power activation circuit is coupled to magnetic motion sensor configured to output a magnetic signal proportional to a measured magnetic field. The low power activation circuit may comprise a digital tracking circuit configured to provide a digital signal that tracks the magnetic field and a difference detector configured to detect a difference between a current digital signal and a prior digital signal stored in a digital storage means. If the detected difference is larger than a digital reference level, an activation signal is output to awaken a system from a sleep mode.

Abstract: A transformer position sensor includes a primary coil, a secondary coil, and an electrically shorted coil. The primary coil is adapted to receive an excitation signal and is configured, upon receipt of the excitation signal, to generate a primary magnetic flux. The secondary coil is inductively coupled to the primary coil upon electrical excitation of the primary coil, and includes a plurality of differentially wound coils. The electrically shorted coil is inductively coupled to receive at least a portion of the primary magnetic flux generated by the primary coil. The electrically shorted coil is configured, upon receipt of at least a portion of the primary magnetic flux, to generate a magnetic flux that opposes the primary magnetic flux.

Abstract: A magnetic field detection device includes: a first magnetic field generating part, including a first magnetic field generating conductor; a first magnetic field detection part, including a first magnetic field detection element and a first differential operation part, wherein a first output of the first magnetic field detection element corresponding to the environment magnetic field is inputted into the first differential operation part, and a first feedback current flows into the first magnetic field generating conductor, and thus the first magnetic field generating part provides the first magnetic field detection element with a first feedback current magnetic field, with a direction opposite to the environment magnetic field; a second magnetic field generating part, including a second magnetic field generating conductor, in which a second current corresponding to the first feedback current flows; and a second magnetic field detection part, including a second magnetic field detection element.

Abstract: A linear variable differential transformer (“LVDT”) including a semiconductor substrate and a plurality of coils formed at least partially on the substrate.

Abstract: A differential transformer type magnetic sensor is disclosed. The drive coil includes a planar coil arranged on a substrate. The first differential coil includes a planar coil arranged on the substrate. The second differential coil includes a planar coil arranged on the substrate and connected to the first differential coil. The first selector unit is used for a zero adjustment of a differential transformer. The first differential coil includes a plurality of first branch lines formed by branching a wire material forming the outermost turn of the first differential coil. The plurality of first branch lines are so arranged that the amount of magnetic fluxes passing along the plurality of respective first branch lines differ when the drive coil is driven. The first selector unit is capable of selecting any one of the plurality of first branch lines and arranged on the substrate.

Abstract: Disclosed are assemblies, systems, devices and methods, including an assembly to determine an angular position of a rotatable structure external to the assembly. The assembly includes a sensor including a rotatable member, a main winding set and at least one auxiliary winding, and also a coupling element to couple the sensor to the external rotatable structure to cause rotation of the rotatable member of the sensor in response to rotation of the external rotatable structure. Resultant voltages at the main winding set and at the at least one auxiliary winding are produced based, at least in part, on an angular position of the rotatable member of the sensor. The angular position of the external rotatable structure is determined based on the resultant voltages at the main winding set and at the at least one auxiliary winding.

Abstract: Sensor having a primary coil, two secondary coils as well as an evaluator. An excitation signal may be applied to the primary coil. An output signal depending on a position of a coupling element may be induced in each secondary coil. An evaluator is configured to evaluate the output signals in order to evaluate a phase offset between the output signals. Further, the evaluator is configured to provide a sensor output signal indicating the position or change in position of the coupling element.

Abstract: A variable reluctance angle sensor includes a stator, a rotor, and a computation section. The stator includes a core member having teeth, which are arranged in a circumferential direction, and excitation coils, which are respectively wound about the teeth such that magnetic poles of the teeth have different polarities alternately in the circumferential direction. An input voltage is supplied to the excitation coils. The rotor radially faces the teeth of the stator. The rotor has a shape such that gap permeance with respect to the stator changes in a sinusoidal fashion in accordance with the rotational angle of the rotor. The computation section obtains output voltages of two or more phases having different phases based on the voltages of the excitation coils, and detects the rotational angle of the rotor based on the output voltages.

Abstract: A stator structure and a VR type resolver, in which the winding of the resolver can be prevented from corroding without increasing the production cost, are provided. The stator structure has stator protruding portions and coils wound around the stator protruding portions, the coils consisting of exciting coils, sine phase detection coils, and cosine phase detection coils, and at least the coils wound at the outermost side are formed by wires in which conductive portions are made of aluminum.

Abstract: The present invention relates to a reluctance resolver (100) with an at least partially soft magnetic stator (104) and an at least partially soft magnetic rotor (102) which oppose each other by forming an air gap. The magnetic resistance in the air gap changes periodically on account of a configuration of the rotor that varies over the circumference. The angle sensor has a magnetic flux transmitter which is arranged on the stator and generates a predefined magnetic flux distribution in the air gap via at least one pair of poles. Furthermore, a magnetic flux receiver, which measures the intensity of the magnetic field via at least two pairs of signal poles arranged offset from one another at an angle, is arranged on the stator, wherein an angle value for a position of the rotor in relation to the stator can be derived from the two receiver signals.

Abstract: A half-bridge variable differential transformer position sensing system that includes a transducer having a stator with an inductive coil having a center tap configured to provide an output signal. The transducer also has an armature with a magnetically permeable core configured to move within the inductive coil, such that movement of the magnetically permeable core causes a change in the output signal. The position sensing system includes a first circuit configured to provide an excitation signal at one terminal of the inductive coil. The system includes no more than three electrical interface wires, and a microcontroller configured to calculate the degree of change in the position of the magnetically permeable core, and is configured to correct for variations in the voltage of the output signal due to the temperature of the transducer and due to non-linear effects on the output signal caused by movement of the magnetically permeable core.

Abstract: A method for determining direction of travel of a tag is described. The method includes a tag that receives sample signals from two spatially separate LF magnetic fields generated by an exciter. The received signal strength indicator (RSSI) data associated with each of the sample signals is determined. A first RSSI profile is created for the first LF magnetic fields. A second RSSI profile is created for the second LF magnetic fields. The first and second RSSI profiles are compared to determine a direction of travel of the object. A tag, an exciter and a computer readable medium are configured to facilitate the method.

Abstract: An electromagnetic induction type absolute position measuring encoder having two or more rows of scale coils, each of the rows having a scale pitch different from that of another row; a transmitter coil and a receiver coil arranged on a grid that is movable relative to the scale in the measuring direction so as to face the scale coils; and the track is constituted by the scale coils, the transmitter coil and the receiver coil. The encoder is capable of measuring an absolute position of the grid with respect to the scale from a flux change detected at the receiver coil via the scale coils when the transmitter coil is excited, in which at least one loop-shaped additional scale coil is added between the scale coils in at least one of the tracks.