Abstract: An electric motor (2) has a base motor module (3) and an electronic module (18) which is electrically and mechanically connected to the base motor module (3) and comprises an electronics housing (12). The base motor module (3) comprises a flange plate (8) which forms an interference fit with the electronics housing (12). The flange plate (8) may have an opening (36) with a circumferential collar (39) which engages in a fastening passage (35) of the electronics housing (12) and forms the interference fit with the electronics housing (12).

Abstract: A system for distinguishing target metal objects from each other in close proximity to each other. The method includes transmitting a first sinusoid signal via a first transmit coil to a first receive coil in close proximity to the first transmit coil; transmitting a second sinusoidal signal at a second frequency and amplitude different from the first frequency and amplitude to a second receive coil arranged in close proximity to the second transmit coil and in close proximity to the first receive coil such that received signals in the first and second receive coils include first and second frequency signals from the other of the first and second transmit coils. The received signals are separated via frequency domain multiplexing. The signals are compared to detect a presence of the target having a signal magnitude different from the first received signal and the received second signal and a known reference point.

Abstract: An apparatus for inductive linear-position sensing is disclosed. An apparatus may include a support structure and an electrically conductive material defining a continuous path for electrical current to flow between a first location and a second location. The continuous path may include: a first path portion defining a first spiraling path for the electrical current to flow in a clockwise direction around a first axis; a second path portion laterally spaced from the first path portion and defining a second spiraling path for the electrical current to flow in a counter-clockwise direction around a second axis; a first coupling portion coupling an inner portion of the first path portion to an inner portion of the second path portion; and a second coupling portion coupling an outer portion of the second path portion to an outer portion of the first path portion. Related systems, devices, and methods are also disclosed.

Abstract: A hybrid position sensor for determining the position of a hybrid target includes a main transducer for obtaining a first signal indicative for a position of the hybrid target within a first range and with a first resolution using a first or second technology; a support transducer for obtaining a second signal indicative for the position of the hybrid target within a second range and with a second resolution using the second technology if the main transducer is using the first technology and vice versa, wherein the first range is smaller than the second and the first resolution is higher than the second, and wherein the first technology is magnet based and the second technology is an inductive technology; a combiner for combining the obtained first signal and second signal to determine the position of the hybrid target.

Abstract: An inductive sensor includes a first circuit board having a sensor element configurable in a plurality of different coil configurations. The sensor element includes a transmit coil and a plurality of receive coils. The first circuit board includes interconnect points positioned at a same location on the first circuit board for each of the plurality of different coil configurations. The inductive sensor includes a second circuit board spaced apart from the first circuit board along the axial direction. The second circuit board includes processing circuitry associated with the sensor element and configurable in a plurality of different configurations. The second circuit board includes interconnect points positioned at a same location on the second circuit board for each of the configurations of the processing circuitry. Furthermore, each interconnect point on the second circuit board is aligned with a corresponding interconnect point on the first circuit board along circumferential and radial directions.

Abstract: An inductive type position encoder includes a scale, a detector portion and a signal processor. According to one aspect, field generating elements and sensing elements of the detector portion are provided on opposite sides of the scale such that at least part of the scale is between the field generating elements and the sensing elements (transmissive configuration). According to another aspect, the scale comprises a periodic scale pattern including signal modulating elements that are disposed along a scale direction, which is not parallel to a measuring axis direction of the encoder and is slanted at a scale angle relative to the measuring axis direction, such that there is a corresponding y-direction displacement for a given x-direction displacement of the encoder. These aspects of the disclosure make it possible to design a very compact inductive type position encoder, including one capable of indicating an absolute position along the scale.

Abstract: An inductive type position encoder includes a scale, a detector portion and a signal processor. According to one aspect, field generating elements and sensing elements of the detector portion are provided on opposite sides of the scale such that at least part of the scale is between the field generating elements and the sensing elements (transmissive configuration). According to another aspect, the scale comprises a periodic scale pattern including signal modulating elements that are disposed along a scale direction, which is not parallel to a measuring axis direction of the encoder and is slanted at a scale angle relative to the measuring axis direction, such that there is a corresponding y-direction displacement for a given x-direction displacement of the encoder. These aspects of the disclosure make it possible to design a very compact inductive type position encoder, including one capable of indicating an absolute position along the scale.

Abstract: The present invention relates to a big data-based battery inspection method. Specifically, the present invention is for providing a big data-based battery inspection method which applies information on a metal part of a battery measured by an eddy current sensor to a discrimination function so as to quickly inspect the state of the metal part.

Abstract: An electronic device is configured to be installed in a mobile body. The electronic device comprises an electric field generator, an electric field detector, and a controller. The electric field generator is configured to generate an electric field in a predetermined range. The electric field detector is configured to detect the electric field generated by the electric field generator. The controller is configured to detect an object in the predetermined range based on a change of the electric field detected by the electric field detector. The controller is configured to control the mobile body based on a result of detecting the object.

Abstract: Examples disclosed herein relate generally to inductive angular-position sensors. An example apparatus may include a support structure, a first inductive angular-position sensor, a second inductive angular-position sensor, and a shield. The first inductive angular-position sensor may include a respective first sense coil arranged at a first portion of the support structure. The respective first sense coil may at least partially circumscribe an axis. The second inductive angular-position sensor may include a respective first sense coil arranged opposite the first sense coil of the first inductive angular-position sensor at a second portion of the support structure. The first sense coil of the first inductive angular-position sensor may at least partially circumscribe the axis. The shield may be arranged between the first sense coil of the first inductive angular-position sensor and the first sense coil of the second inductive angular-position sensor.

Abstract: A vernier sensor including a coarse sensor and a fine sensor may require calibration to ensure accurate position measurements. Calibration may include determining coefficients for harmonics that can be added to the coarse sensor output and the fine sensor output to reduce harmonic distortion. The disclosure describes using the offset and variance of a difference signal as the basis for calibration. This approach is possible at least because the frequencies of the coarse sensor and fine sensor can be selected to reduce the complexity of these calculations.

Abstract: A method and apparatus for reducing magnetic tracking error in the position and orientation determined in a magnetic tracking system having a magnetic field generator. In some embodiments, the measured position and orientation of a sensor is compared to an expected theoretical position and orientation. Any error is assumed to be from “floor distortion,” i.e., eddy currents in the floor caused by the magnetic field generated by the magnetic field transmitter. The floor distortion is modeled as being caused by eddy currents caused by a second magnetic field transmitter that is a reflection of the actual transmitter. An algorithm iteratively searches over a parameter space to minimize the difference between the measured position and orientation and the theoretical position and orientation, and applies a correction to the measured position and orientation. The measurements and corrections of the position and orientation run in real-time with no additional hardware or calibration required.

Abstract: An inductive position measuring sensor comprises a fixed ruler and a sliding ruler which can move relatively along the direction of the measuring axis. A series of coupling coils are made on the fixed ruler in the measuring direction,-two sets of driving coils are disposed on the sliding ruler, and induction coils in a staggered manner are also disposed on the sliding ruler. The two sets of driving coils generate excitation signals, by interaction with the coupling coils on the fixed ruler, and being received by the induction coils of the sliding ruler, they are used for measuring the relative movement of the fixed ruler and the sliding ruler. By controlling the positions and winding directions of the driving coils and the induction coils, the sensor can effectively inhibit the direct space signal interference of the driving coils to the induction coils, and the signal-to-noise ratio is improved.

Abstract: The electromagnetic induction displacement sensor consists of a transceiver board and an excitation board that may move relative to each other along a measuring path. The transceiver board is arranged with at least one transmitter winding and at least two three-phase receiver windings with different pitches, the number of three-phase receiver windings is one more than that of transmitter windings. Each transmitter winding encircles two three-phase receiver windings with different pitches in the same direction in series, and all receiver windings are in a distributed winding structure. The excitation board is arranged with at least two rows of excitation coils in the shape of short-circuit loop, the number of rows of excitation coils is equal to the number of the three-phase receiver windings on the transceiver board, respectively aligning with corresponding three-phase receiver winding and having the same pitch.

Abstract: A position detector for a passenger service unit which can be installed in a passenger service channel. The position detector includes a sensor rail which has a multiplicity of sensors and is configured to be fitted in the longitudinal direction of the passenger service channel. The position detector also includes a position marker which is configured to be fastened to the passenger service unit and to trigger a sensor signal at one of the multiplicity of sensors. A passenger service channel having a position detector and a vehicle area having a passenger service channel are also described.

Abstract: The described techniques are directed to inductive torque sensors that implement independent target coil and pickup coil systems. By utilizing the various principles of inductive angle sensors, and as a result of the specific physical arrangement of target coils, the inductive torque sensor may independently obtain a rotational position (i.e., mechanical angle) of the rotatable input shaft via one pickup coil system, and a rotational position (i.e., mechanical angle) of the rotatable output shaft via another pickup coil system. Combiner circuitry is also provided to calculate the torsion angle using the signals induced in each of two separate pickup coil systems. By using different k-fold symmetry periodicities in the target coils with respect to the coil configurations, the inductive torque sensor advantageously reduces or eliminates mutual coupling between the different target coil systems and provide robustness to stray or external electromagnetic fields.

Abstract: A method for determining a rate of sedimentation or of creaming of a mixture in suspension, including an application of a sample of the mixture in suspension to a photonic microresonator, an application of a first optical signal at the input of the photonic microresonator carrying the sample of the mixture in suspension, an acquisition and a recording of a second optical signal, delivered at the output of the microresonator carrying the sample of the mixture in suspension, and a determination of information representing a rate of sedimentation or of creaming of the mixture from the recorded second signal, by successive iterations of spectral analysis of the second optical signal.

Abstract: A sensor front-end is presented for processing a measurement signal from a sensing unit, wherein the sensing unit is configured to receive a stimulus signal from an evaluation unit of the sensor front-end, generate the measurement signal from the stimulus signal by altering an amplitude of the stimulus signal based on a measurement parameter, and provide the measurement signal to the evaluation unit. The sensor front-end comprises the evaluation unit that is configured to generate a simulated measurement signal from the stimulus signal by controlling an amplitude of the stimulus signal based on a predetermined control variable, to generate a simulated output signal based on the stimulus signal and the simulated measurement signal, and to determine an error condition based on a comparison of the simulated output signal and the predetermined control variable or a signal derived from the predetermined control variable.

Abstract: The present disclosure relates to a displacement sensor. A displacement sensor according to the embodiment of the present disclosure includes a coil structure consisting of wound coil, a shield member formed to surround an outer periphery of the coil structure and a housing, wherein the housing comprises an upper side wall part surrounding an outer periphery of the shield member and a lower side wall part formed to extend from the upper side wall part, wherein an inner circumferential surface of the lower side wall part is protruded toward the inside of the housing more than an inner circumferential surface of the upper side wall part, wherein an outer circumferential surface of the lower side wall part may include a depressed region formed to be depressed into the inside of the housing by a predetermined depth.

Abstract: Location systems and methods for locating paint and other markings on a surface are disclosed. A paint marking stick may include a magnetic field sonde that is actuated in conjunction with dispensing of paint or other markers, where the sonde generates a magnetic field signal in conjunction with dispensing of paint or placement of a marker. A corresponding utility locator may receive the sonde magnetic field dipole signal and determine and store positional information and type information associated with the paint or other marker.

Abstract: Provided is an inspection device for a rotating electric machine, including: a storage unit configured to store tendency information indicating a relationship among a position of damage that occurs in an inspection target portion being a range to be inspected of a rotor included in a rotating electric machine, a scale of the damage, and an amount of deformation that occurs in a measurement target portion set on an outer surface of the rotor; a measurement unit configured to measure the amount of deformation that has occurred in the measurement target portion; and a damage estimating unit configured to estimate the position and the scale of the damage that has occurred in the measurement target portion based on the tendency information and the amount of deformation in the measurement target portion, which has been measured by the measurement unit.

Abstract: Methods and apparatuses to obtain increased performance and differentiation for an inductive position sensor through improvements to the sense element and target design are disclosed. In a particular embodiment, a sense element includes a transmit coil, a first receive coil that includes a first plurality of arrayed loops, wherein two or more of the first plurality of arrayed loops are at least one of phase blended and amplitude arrayed, and a second receive coil that includes a second plurality of arrayed loops, wherein two or more of the second plurality of arrayed loops are at least one of phase blended and amplitude arrayed, and wherein the first receive coil and the second receive coil are phase shifted. The sense element coils are arrayed in several geometries and layouts, and the coil and target geometry are manipulated to compensate for inherent errors in the fundamental design of an inductive position sensor.

Abstract: A device includes a substrate with an excitation coil configured to generate a magnetic field in reaction to an input signal fed in, and with a pickup coil arrangement configured to generate an output signal in reaction to a magnetic field. The excitation coil includes one or more turns arranged around the pickup coil arrangement in a ring-shaped manner in a plan view of the substrate plane. The device further includes a chip package comprising at least one electrical connection connected to the pickup coil arrangement by means of a signal-carrying conductor. In accordance with the concept described herein, the chip package is positioned on the substrate in such a way that the signal-carrying conductor and the one or more turns of the excitation coil do not overlap in a plan view of the substrate plane.

Abstract: At least one magnetic field actuator is configured for generating an actuated magnetic field that at least partially cancels an outside magnetic field, thereby yielding a total residual magnetic field. A plurality of magnetometers are configured for taking measurements of the total residual magnetic field. The magnetometers include a plurality of coarse magnetometers and a plurality of fine magnetometers. A processor is configured for acquiring the total residual magnetic field measurements from the coarse magnetometers, estimating the total residual magnetic field at the fine magnetometers based on total residual magnetic field measurements acquired from the plurality of coarse magnetometers, and controlling the actuated magnetic field at least partially based on the total residual magnetic field estimates at the fine magnetometers in a manner that suppresses the total residual magnetic field at the fine magnetometers to a baseline level, such that at least one of the fine magnetometers is in-range.

Abstract: A shaft monitoring system includes a rotatable shaft having a target element coupled thereto that rotates along with the shaft. A proximity sensor is located adjacent to the target element. The proximity sensor measures an inductance of the target element based on one or both of a volume of the target element and a distance between the target element and the proximity sensor, and generates a proximity sensor output signal based on the measured inductance. A signal processing system determines at least one of a position of the shaft, a rotational speed of the shaft, and a rotational direction of the shaft based on the proximity sensor output signal.

Abstract: An improved inductive sensor determines angular positions for rotating objects, such as rotors of synchronous electric motors. The inductive sensor includes an arcuate transmitter coil, one or more receiver coils, and a conductive target configured to rotate with the rotating object, relative to the transmitter coil and the receiver coil(s). The conductive target includes a plurality of lobes and individual of the lobes is split into multiple lobe portions.

Abstract: A method for detecting a position and an operating state of an active surgical instrument. The active surgical instrument emits or influences/modifies at least one electromagnetic field in an active operating state. The method includes the steps of positioning a first sensor in order to detect the electromagnetic field emitted or influenced by the active surgical instrument is the active operating state at a known position, detecting the electromagnetic field emitted or influenced by the active surgical instrument in the active operating state by means of the first sensor, generating an output signal by means of the first sensor, the output signal indicating the detection of the electromagnetic field emitted or influenced by the active surgical instrument by means of the first sensor, and ascertaining the position and operating state of the active surgical instrument on the basis of the output signal and the known position of the first sensor.

Abstract: In one example implementation, a rotary position sensor can include a first member and a second member, one of the first and second members having a transmit aerial and a receive aerial and the other of the first and second members having an intermediate coupling element. The receive aerial has at least one receive conductive winding arranged to form a first set of current loops and a second set of current loops. The intermediate coupling element comprises a conductive material arranged in a pattern. The pattern of the intermediate coupling element and the layout of the first and second set of current loops are mutually arranged such that any electromotive force induced in the first set of current loops by a background magnetic field is substantially balanced by an electromotive force induced in the second set of current loops by the background magnetic field.

Abstract: A torque sensor can be configured to detect the positions of rotor targets relative to the position of respective receiver structures. A torque sensor can include an oscillator circuit coupled to an excitation coil. The oscillator circuit can be configured to generate a periodic voltage signal and energize the excitation coil with the periodic voltage signal. The inductive torque sensor can include a stator circuit board including receivers with receiver structures that are periodically repeated. The inductive torque sensor can include rotor targets coupled to respective rotors, the rotor targets can be configured to affect the strength of the inductive coupling between the excitation coil and the respective receivers. The inductive torque sensor can include processing circuitry configured to provide signals associated with positions of the rotor targets relative to their respective receiver structures.

Abstract: A position sensor is provided. The position sensor includes a target and a segment sensor element. The segment sensor element defines a circumferential direction and a radial direction. The segment sensor element includes a transmit coil. The segment sensor element includes a plurality of receive coils positioned within a space defined by the transmit coil. The plurality of receive coils are offset relative to one another. The shape of each of the plurality of receive coils corresponds to a periodic waveform having a radial width that varies along the circumferential direction. Furthermore, the shape of at least one receive coil of the plurality of receive coils is distorted along at least one of the radial direction or the circumferential direction.

Abstract: A sensor system and method of operating the sensor system can include an indicator that is operable in resonance, the indicator being connected to a movable element of an actuator, and a sensor including sensor windings arranged in direct proximity to the indicator and external to a closed housing. The sensor can receive a position or an angle of the indicator, and can measure the position or the angle of the movable element inside the actuator through the closed housing based on inductive resonance facilitated by the indicator.

Abstract: An inductive sensor device has a coil arrangement and sensor electronics for determining a longitudinal position of an at least partially electrically conductive and/or magnetically polarizable object moveable at a distance from a device end face along a device sensitive axis. The arrangement has a substantially planar exciting coil for producing an alternating magnetic field for inducing eddy currents and/or magnetic polarization in the object and a first substantially planar receiving coil substantially parallel to and overlapping the exciting coil. The coils are substantially parallel to the end face. The sensor electronics determine at least one parameter of an exciting coil electrical signal, which is variable owing to an inductive backward effect of the object, at least one parameter of a voltage inducible in the at least first receiving coil based on this effect, and the longitudinal position from the determined signal parameter and the determined voltage parameter.

Abstract: A redundant angular position sensor comprising a first angular position sensor including a first excitation coil, a first sensing coil and a second sensing coil and a second angular position sensor. The second angular position sensor including a second excitation coil, a third sensing coil and a fourth sensing coil. Each of the first, second, third and fourth sensing coils comprising a respective clockwise winding portion and a respective counter-clockwise winding portion. The redundant angular position sensor further comprises a rotatable inductive coupling element positioned in overlying relation to the sensing coils and separated from the sensing coils by a gap, wherein the rotatable inductive coupling element comprises four, substantially evenly radially spaced, sector apertures.

Abstract: An inductive sensing-based user interface device which includes a conductive barrier with at least one aperture, a magnetic flux modifier attached to a rotary member on one side of the barrier and an inductive structure on an opposed side of the barrier aligned with the aperture, magnetically coupled to the flux modifier, wherein a change in sensed inductance is used to determine rotational input.

Abstract: An inductive angle sensor includes an inductive target arrangement with k-fold symmetry and a first pickup coil arrangement with k-fold symmetry and a second pickup coil arrangement with k-fold symmetry. A combination apparatus is designed to combine signals of the first pickup coil arrangement with signals of the second pickup coil arrangement and, on the basis thereof, to ascertain an angle-error-compensated rotation angle. The single pickup coils of the first and second pickup coil arrangements are each rotationally offset about the axis of rotation R by a geometric offset angle ? relative to one another. Additionally, the entire first pickup coil arrangement is rotationally offset relative to the entire second pickup coil arrangement about the axis of rotation R by a geometric offset angle ?.

Abstract: An inductive angle sensor for determining a rotational position of a rotor relative to a stator includes an exciter coil, at least one pickup coil arrangement having an m-fold symmetry and at least one conductive target having an m-fold symmetry. The exciter coil may excite the conductive target which, in turn, may induce an induced signal in the pickup coil arrangement. A signal analysis device may determine the rotational position of the rotor based on the induced signal. The inductive angle sensor may comprise a second pickup coil arrangement having an n-fold symmetry and a second conductive target having an n-fold symmetry. The exciter coil may excite the second conductive target which, in turn, may induce a second induced signal in the second pickup coil arrangement. The signal analysis device may determine the rotational position of the rotor based on the two induced signals according to a Vernier principle.

Abstract: A Usage, Condition and Location System (UCLS) tag is provided, which is an active RFID tag that, in addition to location, is configured to determine the usage state and operating condition of a device. The UCLS tag includes sensors that measure physical activity of the associated equipment (vibration, magnetic activity, temperature, etc.). Algorithms may use the information obtained from the UCLS tags to map the measured sensor data to a contextual usage state and operating condition of the device.

Abstract: Buried utility locator systems, including a camera, for detecting buried utilities and determining information therefrom based on sensing electromagnetic emissions from the buried utilities are disclosed. Images and/or video captured by the camera are stored in association with the determined information in a non-transitory memory.

Abstract: An inductive angle sensor is provided with a stator with an excitation oscillating circuit and a pickup coil arrangement and also with a rotor which is arranged rotatably with respect to the stator and comprises an inductive target arrangement. The excitation oscillating circuit can be energizable with an alternating current, in order to induce an induction current in the target arrangement, and the target arrangement can be designed to generate a magnetic field in reaction to the induction current, which magnetic field in turn generates induction signals in the pickup coil arrangement. The angle sensor further comprises a circuit that is designed to derive an induction strength signal representing the signal strength of the induction signals from the induction signals and to ascertain the spatial clearance between the rotor and the stator on the basis of the induction strength signal, and to generate a corresponding clearance signal.

Abstract: A rotary position sensor is includes a static portion that comprises a first board and a second board and a rotatable portion that comprises a third board. The second board comprises a first planar coil; and the third board comprises a second planar coil as well as means for generating luminance. The first board comprises means for receiving the generated luminance and the first planar coil of the second board is configured to transmit power to said second planar coil of said third board via inductance. The power received by said second planar coil is configured to supply a current to said means for generating luminance; and said means for generating luminance is configured to emit a luminance signal which has a luminance level.

Abstract: An apparatus and method for implementing a technique for adaptively assigning weighting factors to position and orientation determinations in an electromagnetic or hybrid tracking system having multiple transmitters or multiple receivers. The apparatus may reduce the impact of eddy current distortion to the position and orientation determinations.

Abstract: A magnetostrictive position measuring method determines a time of flight of a magnetostrictive response transmitted through a waveguide. The magnetostrictive response is generated using a target magnet in response to a magnetostrictive excitation. In the method, an electrical response signal containing an indicator of the magnetostrictive response is digitally sampled at a sampling rate to obtain a plurality of samples. An amplitude of each of the plurality of samples within a target frequency range is determined through an analysis of the plurality of samples in a frequency domain. A peak sample from the plurality of samples in the frequency domain corresponding to the magnetostrictive response is identified. The time of flight and a position of the target magnet along the waveguide is determined based on the peak sample.

Abstract: An offset correction device includes: an amplitude adjuster that adjusts an amplitude of a detection signal output from an encoder by adjusting a gain of the detection signal so that the amplitude is within a predetermined range; an offset corrector that corrects an offset of an amplitude center of the detection signal; and a storage that stores a relationship between the gain and an offset amount in advance, wherein the offset corrector refers to the relationship stored in the storage when the amplitude adjuster changes the gain, obtains the offset amount corresponding to the changed gain, and corrects the offset based on the obtained offset amount.

Abstract: The present invention relates to an inductive position sensor configured to determine a position of a target device. The inductive position sensor comprises at least two coils for determining the position. At least two of the at least two coils for determining the position at least partially overlap. At least one coil of the at least two at least partially overlapping coils is a transmitter coil and at least one of the at least two coils is a receiver coil. At least one of the at least two coils has N2+R portions substantially equally distributed over N substantially parallel planes, N being an integer larger than or equal to two and R an integer larger than or equal to zero. For each of the at least two coils the portions distributed over the N substantially parallel planes are substantially identical, so that mutual inductance between the at least two coils is substantially unaffected by misalignments between the N substantially parallel planes.

Abstract: A measuring arrangement for distance or angle measurement and a corresponding measuring method are described. In accordance with one example, the measuring arrangement comprises a scale having magnetization which varies along a measuring direction and which brings about a correspondingly varying magnetic field. The measuring device furthermore comprises at least one scanning head which is permeated by the varying magnetic field depending on the relative position with respect to the scale in the measuring direction. The scanning head comprises the following: at least one ferromagnetic film having, on account of the magneto impedance effect, a local electrical impedance that is dependent on the magnetic field and varies along the measuring direction, and at least one sensor unit configured to generate at least two phase-shifted sensor signals which are dependent on the local electrical impedance of the film.

Abstract: Method and system for determining a confinement size in a porous media, including subjecting the media to a substantially uniform static magnetic field, applying a magnetic resonance pulse sequence to the media, detecting magnetic resonance signals from the media, determining non-ground eigenvalues from the magnetic resonance relaxation spectrum, and determining a confinement size of the media from the eigenvalues.

Abstract: A device rotates at least one static magnetic field about an axis, producing a rotating magnetic dipole field, and is movable in relation to the surface of the ground. The field is periodically sensed using a receiver to produce a receiver output responsive to the field. A positional relationship between the receiver and the device is monitored using the output. In one aspect, changing the positional relationship, by moving the device nearer to a boring tool which supports the receiver, causes an increase in accuracy of depth determination. In another aspect, determination of an actual overhead position of the boring tool, and its application, are described. Use of a plurality of measurements over at least one-half revolution of each magnet is disclosed. Establishing a surface radial direction toward a boring tool and resolution of multi-valued parameters is described. Calibration techniques, as well as a three transmitter configuration are also described.

Abstract: A system and method for monitoring a pitch system of a wind turbine includes monitoring, via one or more first sensors, at least one electrical condition of the pitch system. The method also includes monitoring, via one or more second sensors, at least one mechanical condition of the pitch system. Further, the method includes receiving, via a controller communicatively coupled to the one or more first and second sensors, sensor signals representing the at least one electrical condition and the at least one mechanical condition of the pitch system. Thus, the method includes determining, via the controller, a bearing condition of a pitch bearing of the pitch system based on the at least one electrical condition and the at least one mechanical condition of the pitch system.

Abstract: Head-mounted augmented reality (AR) devices can track pose of a wearer's head to provide a three-dimensional virtual representation of objects in the wearer's environment. An electromagnetic (EM) tracking system can track head or body pose. A handheld user input device can include an EM emitter that generates an EM field, and the head-mounted AR device can include an EM sensor that senses the EM field. EM information from the sensor can be analyzed to determine location and/or orientation of the sensor and thereby the wearer's pose. The EM emitter and sensor may utilize time division multiplexing (TDM) or dynamic frequency tuning to operate at multiple frequencies. Voltage gain control may be implemented in the transmitter, rather than the sensor, allowing smaller and lighter weight sensor designs. The EM sensor can implement noise cancellation to reduce the level of EM interference generated by nearby audio speakers.

Abstract: A method of reducing a chance of interference between operations of two electromagnetic systems (e.g., AR/VR systems) is provided. The method includes determining one or more first frequencies at which a first electromagnetic system is operating, identifying one or more second frequencies that do not interfere with the determined one or more first frequencies, and setting a second electromagnetic system to operate at the identified one or more second frequencies. Each of the first and the second electromagnetic systems includes a respective magnetic transmitter configured to generate magnetic fields, and a respective magnetic sensor configured to generate signals based on characteristics of the magnetic fields received at the magnetic sensor (e.g., from the respective magnetic transmitter).