Abstract: A wear monitoring device for rolling elements in a machine element has at least one magnet generating a measuring magnetic field, and a magnetic field sensor arrangement for measuring a flux density of the measuring magnetic field. The sensor arrangement has at least one first magnetic field sensor for measuring the flux density at a first measuring position and a second magnetic field sensor for measuring the flux density at a second measuring position at a distance from the first measuring position. The measuring positions are selected such that rolling elements passing the measuring positions are in close contact with one another and a resulting change in the measuring magnetic field is detectable at a measuring position by the respective magnetic field sensor. An evaluation unit records and evaluates the flux densities measured by the magnetic field sensors, to determine diameters and/or changes in the diameters of the rolling elements.

Abstract: A system for driving an ultrasonic device for bone cement removal and/or osteotomy operations comprises a control unit, a memory unit, and a connector for connecting together the control unit and a handset of the ultrasonic device. The control unit is configured to send a signal to the handset, receive from the handset a response to the signal sent, and check an operating condition of the ultrasonic device based on this response. Related device, method and computer program are also disclosed.

Abstract: Systems and methods are presented for a swallowable pH sensor made entirely of edible and digestible materials. A substrate is provided and an electrical circuit pattern is printed on a top surface of the substrate. The electrical circuit pattern includes a plurality of interdigitated electrodes and an antenna portion. The substrate is rolled into a cylindrical form such that the interdigitated electrodes are positioned on an outermost layer of the rolled substrate. The rolling of the substrate also causes the antenna portion of the electrical circuit pattern to form into a coil shape.

Abstract: An eddy-current angular displacement sensor includes a stator including a coil array including N coils, wherein N is an integer greater than 1, one exciting circuit connected via a switching system to the coil array that generates a changing magnetic field, a measuring circuit connected via a switching system to the coil array that generates output signals that depend on the eddy currents caused by the changing magnetic field, and a partially metallized rotor, through which the eddy currents travel, and the angular displacement of which would be determined by the output signals.

Abstract: A method for management of a land base includes interfacing a machine or equipment to a computer running a geographical information system (GIS) application such that the computer is configured to monitor the operations performed by the equipment or machine on the land base and store the operations as map points, lines, or polygons on at least one data layer within the GIS application. The method further includes displaying the GIS application to the operator at the point and time of performing the operations.

Abstract: An apparatus includes a digitally controlled oscillator (DCO), which includes an inductor coupled in series with a first capacitor. The DCO further includes a second capacitor coupled in parallel with the series-coupled inductor and first capacitor, a first inverter coupled in parallel with the second capacitor, and a second inverter coupled back-to-back to the first inverter. The DCO further includes a digital-to-analog-converter (DAC) to vary a capacitance of the first capacitor.

Abstract: A method of monitoring a microelectromechanical systems (MEMS) oscillating structure includes: driving the MEMS oscillating structure configured to oscillate about a rotation axis according to an operating response curve during which the MEMS oscillating structure is in resonance, wherein the MEMS oscillating structure is a non-linear resonator; inducing an oscillation decay of the MEMS oscillating structure at predefined tilt angle such that an oscillation of the MEMS oscillating structure decays from the predefined tilt angle over a decay period; measuring at least one characteristic of the oscillation decay; and determining a mechanical health of the MEMS oscillating structure based on the at least one characteristic of the oscillation decay.

Abstract: The present invention provides a system and method which includes a machine learning module which analyzes data collected from one or more sources such as UAVs, satellites, span mounted crop sensors, direct soil sensors and climate sensors. According to a further preferred embodiment, the machine learning module preferably creates sets of field objects from within a given field and uses the received data to create a predictive model for each defined field object based on detected characteristics from each field object within the field.

Abstract: The present invention provides a method for detecting petroleum with a staggered toroidal chip, comprising the following steps: step 1, dry the test environment of a terahertz spectrum analysis system, measure a spectrum under dry conditions, and use the spectrum as a reference spectrum; step 2, use a pipette to transfer a crude oil sample and evenly smear it on the metasurface of a staggered toroidal chip; step 3, put the staggered toroidal chip coated with the crude oil sample into the dried terahertz spectrum analysis system, let a terahertz pulse signal of the terahertz spectrum analysis system to be vertically irradiated on the chip for detection, and then get a detection spectrum of the crude oil sample; step 4, subtract the reference spectrum from the detection spectrum, and then get a transmission spectrum of the crude oil sample, wherein the staggered toroidal chip is a terahertz chip designed based on the dual-torus toroidal effect.

Abstract: A fingerprint recognition technology is disclosed. More specifically, embodiments of the present invention provide a fake fingerprint identification device and a method for driving the identification device. According to the device and the method, an alternating voltage is applied to read a fingerprint such that the fingerprint is identified and physical authentication is made whether the fingerprint is live or fake when the frequency of a TX or RX ultrasonic signal generated by the application of the alternating voltage varies. Therefore, the device and the method can be used to accurately identify whether a fingerprint is live or fake and is thus effective in preventing harmful effects caused when a fake fingerprint is authenticated.

Abstract: An industrial process field device includes a piezoelectric transducer, a sensor circuit, a test circuit, a controller and a communications circuit. The sensor circuit generates a sensor signal indicating a process variable based on a voltage across the piezoelectric transducer. The test circuit is configured to apply a voltage pulse having a pulse voltage to the piezoelectric transducer that induces a response signal, and capture peak positive and negative voltages of the response signal. The controller calculates a current condition value of the piezoelectric transducer based on the peak positive voltage, the peak negative voltage and the pulse voltage, and generates a diagnostic test result based on a comparison of the current condition value to a reference condition value corresponding to a properly operating piezoelectric transducer. The communications circuit communicates the process variable and the diagnostic test result to an external control unit over a process control loop.

Abstract: A touch device according to an exemplary embodiment includes: a plurality of touch electrodes; and a driver/receiver that applies driving signals, each having a frequency corresponding to a resonance frequency of a stylus pen, to the plurality of touch electrodes, and receives detection signals from the plurality of touch electrodes, wherein the driving signals may include a first driving signal and a second driving signal, each having a different phase.

Abstract: A power supply and signal transmitting device for a sensing bolt and sensing bolt device is provided. The power supply and signal transmitting device, which is applied to the sensing bolt including a first contact set, includes a cap module and a supply module. The cap module caps one end of the sensing bolt and includes a cap circuit board module. A second contact set of the cap circuit board module contacts the first contact set for electrically connecting the sensing bolt. The supply module is interposed into the cap module for supplying an external power to the sensing bolt or accessing the data stored in the sensing bolt by electrically connecting a third contact set of the cap circuit board module with a fourth contact set of the supply module. Thereby, the power duration of the sensing bolt may be improved.

Abstract: The present invention relates to an oscillating sensor for a measurement device comprising: an oscillator comprising a resonance circuit for providing an oscillation signal; a gain stage configured to feedback to the resonance circuit to inject energy for excitation of the resonance circuit to maintain oscillation; at least one calibration element to adjust the open loop gain of the oscillator; a calibration unit to provide a modulated calibration control signal to selectively adjust an electrical measure of the at least one calibration element based on at least one predetermined duty cycle, wherein the modulated calibration control signal has an irregularly time-varying cycle frequency.

Abstract: An oscillating sensor device, particularly for a proximity sensor, for sensing a dynamic change of attenuation caused by a measurable physical effect includes an oscillator including a resonance circuit and an amplifier fed back to the resonance circuit and configured to maintain oscillation of the oscillator, and a control unit configured to control the open loop gain of the oscillator. The amplifier comprises a non-linear gain characteristics defining an operating point at a preset amplitude of oscillation. The control unit is configured to control the open loop gain of the oscillator so that the operating point is set to a preset amplitude of the oscillation.

Abstract: Systems and methods are provided for monitoring properties of a microelectromechanical systems (MEMS) oscillating structure. A system includes a MEMS oscillating structure configured as a non-linear resonator to oscillate about a rotation axis; a driver configured to generate a driving force for driving the MEMS oscillating structure about the rotation axis according to an operating response curve during which the MEMS oscillating structure is in resonance, the driver further configured to decrease the driving force when the MEMS oscillating structure is at a predefined tilt angle to induce an oscillation decay of the MEMS oscillating structure; a measurement circuit configured to measure an oscillation frequency and a tilt angle amplitude of the MEMS oscillating structure during a decay period; and processing circuitry configured to determine at least one characteristic of the MEMS oscillating structure based on at least one of the measured oscillation frequency and the measured tilt angle amplitude.

Abstract: An open cell detection method includes: (a) generating a control signal by a control unit, to turn on a first balance switch for a first time period; (b) generating the control signal with the control unit, to turn off the first balance switch for a second time period; (c) measuring a voltage value on a first capacitor, with a measure unit; (d) if the voltage value on the first capacitor is less than an open cell threshold, then determining with the control unit that the first cell has an open cell failure; (e) for each cell of the cells, repeating steps (a)-(d); and (f) if at least one cell of the cells has an open cell failure, then determining with the control unit that the battery management system has an open cell failure.

Abstract: A sensing platform with at least one sensing device to sense underground and above ground environment parameters. A system of sensing environment parameters for a plant using a probe comprising: a first sensor board adapted to sense one or more environment parameters at one or more submerged depth located at flexible points of a location; a second sensor board adapted to done or more environment parameters at one or more surface points located at flexible points of the location; a circuit board adapted to communicate the sensed environment parameters to a central controller; adapted to operate in a low power mode. A system of sensing environment parameters for a field of plants using two or more probes using a fail-over central controller in a double star configuration and/or self learning algorithm.

Abstract: A system includes a fastener and a magneto-elastic component connected to the fastener, wherein a strain level applied to the magneto-elastic component is a function of a tightness level within a range of tightness levels of the fastener. The system further includes a radio frequency identification (RFID) circuit. The system also includes an antenna electrically connected to the RFID circuit. The system includes a variable inductor circuit electrically connected to the RFID circuit and to the antenna, where an inductance exhibited by the variable inductor circuit is a function of the strain level applied to the magneto-elastic component, where a resonance response frequency of the RFID circuit is a function of the inductance exhibited by the variable inductor circuit, and where a change in the strain level results in a shift in the resonance response frequency.

Abstract: In one embodiment, an inductive/LC sensor device includes: an energy storage device for accumulating excitation energy, an LC sensor configured to oscillate using energy accumulated in the energy storage device and transferred to the LC sensor, an energy detector for detecting the energy accumulated in the energy storage device reaching a charge threshold, and at least one switch coupled with the energy detector for terminating accumulating excitation energy in the energy storage device when the charge threshold is detected having been reached by the energy detector.

Abstract: Disclosed is a flow meter and method for measuring water cut and salinity of a multiphase mixture. The water-cut meter includes a conduit configured to receive the multiphase mixture, and a probe array configured to measure a cross-sectional area of the conduit. The probe array includes a plurality of coaxial probes connected in parallel. Optionally, the probe array is configured to operate at a single high frequency, for example, 1 to 3 GHz, to minimize conductivity loss relative to capacitance. The flow meter further includes a processor configured to transmit a signal to the probe array and to receive a reflected signal from the probe array using a single channel. The processor is further configured to calculate the water cut and the salinity of the multiphase mixture based on a single complex permittivity of the multiphase mixture calculated from the received reflected signal.

Abstract: Disclosed is a flow meter and method for measuring water cut and salinity of a multiphase mixture. The water-cut meter includes a conduit configured to receive the multiphase mixture, and a probe array configured to measure a cross-sectional area of the conduit. The probe array includes a plurality of coaxial probes connected in parallel. Optionally, the probe array is configured to operate at a single high frequency, for example, 1 to 3 GHz, to minimize conductivity loss relative to capacitance. The flow meter further includes a processor configured to transmit a signal to the probe array and to receive a reflected signal from the probe array using a single channel. The processor is further configured to calculate the water cut and the salinity of the multiphase mixture based on a single complex permittivity of the multiphase mixture calculated from the received reflected signal.

Abstract: An impedance converter circuit achieves negative capacitance and/or negative inductance for radio frequency (RF) front end impedance matching for low noise amplifier (LNA) designs. The impedance converter circuit includes a first transistor coupled to a first RF input at a source of the first transistor. The impedance converter circuit also includes a second transistor coupled to a second RF input at a source of the second transistor. The second transistor is cross-coupled to the first transistor to form a cross-coupled pair of transistors. The cross-coupled pair of transistors is configured to generate a negative capacitance or a negative inductance based on a load impedance coupled to a drain of the first transistor and a drain of the second transistor.

Abstract: Systems and methods are provided for monitoring properties of a microelectromechanical systems (MEMS) oscillating structure. A system includes a MEMS oscillating structure configured as a non-linear resonator to oscillate about a rotation axis; a driver configured to generate a driving force for driving the MEMS oscillating structure about the rotation axis according to an operating response curve during which the MEMS oscillating structure is in resonance, the driver further configured to decrease the driving force when the MEMS oscillating structure is at a predefined tilt angle to induce an oscillation decay of the MEMS oscillating structure; a measurement circuit configured to measure an oscillation frequency and a tilt angle amplitude of the MEMS oscillating structure during a decay period; and processing circuitry configured to determine at least one characteristic of the MEMS oscillating structure based on at least one of the measured oscillation frequency and the measured tilt angle amplitude.

Abstract: A bolt includes a body and a detecting portion. The body includes a shank and a head provided at one end of the shank. The detecting portion is configured to detect a strain in accordance with an axial force of the shank. The detecting portion includes a memory, a measuring portion, and a transmitting portion. The measuring portion is configured to operate by receiving a first wireless power feed, convert the strain into measurement data, and write the measurement data to the memory. The transmitting portion is configured to operate by receiving a second wireless power feed after the first wireless power feed, read the measurement data stored in the memory, and transmit the read measurement data.

Abstract: Systems and methods are disclosed for a two lead electronic switch adapted to replace a mechanical switch. In one embodiment, a device is provided that includes a sensor and an electronic circuit having a voltage limiting circuit. The electronic circuit is configured to deactivate/activate the voltage limiting circuit to operate the electronic circuit in a first/second state in response to determining that an output of the sensor is less/more than a threshold voltage. The circuit includes first and second terminals configured to receive a switch voltage used to provide power for the device. The device sets the switch voltage to a first voltage level operative to power the electronic circuit and the sensor while the electronic circuit is operating in the first state and to a second voltage level operative to power the electronic circuit and the sensor while the electronic circuit is operating in the second state.

Abstract: A system includes a signal generator configured to generate a signal, the signal being a constant frequency signal or the signal ranging in frequency during a time period. The system includes a probe electrically coupled to the signal generator, and the probe is configured to hover across or touch an encapsulated or uncapsulated strain gauge. The probe includes a coil and a stylus. The coil is configured to receive the signal from the signal generator and generate a magnetic field. The stylus is configured to transmit the magnetic field to the strain gauge. The system includes a data acquisition component coupled to the strain gauge. The data acquisition component is configured to receive stimulus data from the strain gauge, resulting from the magnetic field transmitted by the probe. The data acquisition component is configured to determine whether the stimulus data from the strain gauge is above a threshold, and if so, determine that the strain gauge is operable.

Abstract: A hydration sensor is provided that includes a circulator having a plurality of ports, an amplitude-modulated coherent source connected to a first port of the circulator, a rectifier or other power sensor connected to a second port of the circulator followed by an RF baseband low-noise amplifier, a coupling structure connected to the third port of the circulator, and a demodulator connected to the output of the rectifier. The hydration sensor can include an RF low noise amplifier between the circulator and rectifier, and/or a second amplitude modulator between the circulator and the coupling structure. The coupling structure can be either a guided-wave near-field structure or an interfacial capacitive or inductive element. In the former case, the hydration is determined by measuring the reflectivity of the guided-wave radiation, and in the latter case it is determined by measuring the change of reflectivity (through change of impedance) of the interfacial element.

Abstract: A protective connector includes a core assembly structure, mating pins and a mating coupling structure. The core assembly structure has circuitry mounted therein. The mating coupling structure substantially encases the core assembly structure and mates with another connector such that the mating pins of the protective connector are electrically coupled to pins of the other connector. The mating coupling structure is mechanically free-moving with respect to the core assembly structure such that forces applied to the mating coupling structure to mate the protective connector to the other connector are not applied to the circuitry within the core assembly structure.

Abstract: A device for measuring a measurement variable, wherein a first inductance is replenished with a capacitance to form a parallel resonant circuit and the first inductance is coupled to a measurement inductance.

Abstract: In an embodiment, a method for calibrating a pressure sensor device is disclosed. The method involves determining the resonant frequency of a membrane of the pressure sensor device after the pressure sensor device has been attached to a circuit board, calculating a change in the resonant frequency from a resonant frequency stored in memory, calculating strain of the membrane of the pressure sensor device from the change in resonant frequency, and calibrating the pressure sensor device based on a capacitance-to-pressure curve calculated using the strain of the membrane of the pressure sensor device.

Abstract: A protective connector includes a core assembly structure, mating pins and a mating coupling structure. The core assembly structure has circuitry mounted therein. The mating coupling structure substantially encases the core assembly structure and mates with another connector such that the mating pins of the protective connector are electrically coupled to pins of the other connector. The mating coupling structure is mechanically free-moving with respect to the core assembly structure such that forces applied to the mating coupling structure to mate the protective connector to the other connector are not applied to the circuitry within the core assembly structure.

Abstract: An electromagnetic flowmeter has a flowtube configured to carry a conductive fluid. The flowtube has wall made of a conductive material. The wall has an inner surface surrounding a fluid flow path for the fluid. A non-conductive liner is positioned to electrically insulate the flowtube wall from the fluid. The flowtube and non-conductive liner define an electrode mounting hole. An electrode extends through the electrode mounting hole. The electrode and the non-conductive liner form a fluidic seal between the electrode mounting hole and the fluid flow path. At least a portion of the electrode is arranged in fluid communication with the flowtube within the electrode mounting hole. A short circuit detector can detect failure of the seal when conductive fluid that has leaked past the seal creates a short circuit as a result of the fluid communication between the flowtube and the electrode mounting hole.

Abstract: A level gauge with a control and evaluation electronic comprising a signal generator for generating an alternating voltage, a signal detector for detecting a reflected voltage, a resonant measuring probe, and a connecting element, which connects the evaluating electronic electrically to the measuring probe, with the connecting element comprising a first connecting conductor, which connects the signal generator to the measuring probe, and a second connecting conductor which connects the measuring probe to the signal detector.

Abstract: A method of manufacturing a sensor for in vivo applications includes the steps of providing two wafers of an electrically insulating material. A recess is formed in the first wafer, and a capacitor plate is formed in the recess of the first wafer. A second capacitor plate is formed in a corresponding region of the second wafer, and the two wafers are affixed to one another such that the first and second capacitor plates are arranged in parallel, spaced-apart relation.

Abstract: Disclosed is a flow meter and method for measuring water cut and salinity of a multiphase mixture. The water-cut meter includes a conduit configured to receive the multiphase mixture, and a probe array configured to measure a cross-sectional area of the conduit. The probe array includes a plurality of coaxial probes connected in parallel. Optionally, the probe array is configured to operate at a single high frequency, for example, 1 to 3 GHz, to minimize conductivity loss relative to capacitance. The flow meter further includes a processor configured to transmit a signal to the probe array and to receive a reflected signal from the probe array using a single channel. The processor is further configured to calculate the water cut and the salinity of the multiphase mixture based on a single complex permittivity of the multiphase mixture calculated from the received reflected signal.

Abstract: A controller-implemented method for managing inventory of pallets on a pallet rack is provided. The controller-implemented method may include engaging a plurality of exciters to generate a rack frequency in the pallet rack, receiving the rack frequency at a plurality of corresponding harvesters, detecting variations between the rack frequency generated by the exciters and the rack frequency received by the harvesters, and detecting one or more load characteristics of pallets on the pallet rack based on the variations.

Abstract: A computing device is described that is configured to display a graphic visualization for modeling an irrigation system, such as a center pivot irrigation system. In an implementation, the computing device includes a memory and a processor communicatively coupled to the memory. The computing device also includes one or modules stored in memory and executable by the processor. The one or more modules are configured to instruct the processor to receive a command for placing one or more representations of a center pivot irrigation system within a graphical representation of a cultivation area and to receive one or more operational parameters of the center pivot irrigation system. The one or more modules are also configured to instruct the processor to model operation of the center pivot irrigation system based upon the one or more operational parameters.

Abstract: Devices and methods for the measurement and control of fluid using one or two capacitors are described. The devices use Micro-Electro-Mechanical-Systems (MEMS) and radio-frequency inductive coupling to sense the properties of a fluid in a tube. The single and double capacitor devices may be coupled to shunts implantable in a patient and operable to be interrogated non-invasively. The shunts employing the novel capacitor devices are insensitive to stray signals such as the orientation of a patient's head. The devices are operable to employ a wireless external spectrometer to measure passive subcutaneous components.

Abstract: Pressure measurement system (e.g., for an extracorporeal treatment system), method and pressure pod apparatus including a position sensor for use in repositioning a diaphragm that separates a liquid side cavity from a transducer side cavity (e.g., operatively connected to a pressure transducer); the liquid side cavity being in fluid communication with an inlet and an outlet.

Abstract: A fluid sensor has a first electrode, a second electrode, a housing containing the first and second electrodes, such that the electrodes extend from the housing, exposed metal between the first and second electrodes, and a drive signal electrically connected to the second electrode, such that when fluid is present in the reservoir, either the first electrode senses the presence of the fluid, or the drive signal senses presence of the fluid. A fluid sensor has a first electrode, a second electrode, a housing containing the first and second electrodes, a drive signal electrically connected to the second electrode, and sensing circuitry to measure a current from the second electrode to indicate a fluid level.

Abstract: A printhead with a separate address generator for ink level sensors is described. In an example, a printhead includes drop ejectors fluidically coupled to nozzles, at least one nozzle address generator, nozzle decoders coupled to nozzle address generator(s) and the drop ejectors, ink level sensors each having a sensor circuit in a sensor chamber and a purging resistor circuit, a sensor address generator, and sensor decoders coupled to the sensor address generator and the purging resistor circuit in each of the ink level sensors.

Abstract: Methods, apparatuses, systems, and computer-readable media for integrating sensation functionalities into a mobile device using a haptic sleeve are presented. According to one or more aspects of the disclosure, a computing device may receive, via a haptic sleeve, sensation input captured by one or more haptic components of the haptic sleeve. Subsequently, the computing device may store haptic data corresponding to the received sensation input. For example, in storing such haptic data, the computing device may store information describing one or more electrical signals received via the one or more haptic components of the haptic sleeve during a period of time corresponding to a particular event, and this stored information may reflect various characteristics of the sensation input received by the computing device in connection with the particular event, such as the magnitude(s), position(s), duration, and/or type(s) of sensation(s) captured during the period of time.

Abstract: The invention relates to an inductive proximity switch having a current-fed resonant circuit comprising at least one resonant circuit transmitting coil and a capacitance. The resonant circuit transmitting coil generates an alternating magnetic field, which is able to induct a mutual induction voltage in at least one receiving coil, and the oscillation state of the resonant circuit can be influenced by a metallic release entering or moving away from the alternating field, having an evaluating circuit for obtaining a switching signal from the change in the oscillation state of the resonant circuit, the change in the complex coupling between the at least two coils, namely transmitting coil and receiving coil, being evaluatable with the aid of an auxiliary voltage signal as a switching signal in the presence or absence of the release.

Abstract: A system and method for autonomously scanning a sensor panel device is disclosed. A sensor panel processor can be disabled after a first predetermined amount of time has elapsed without the sensor panel device sensing any events. One or more system clocks can also be disabled to conserve power. While the processor and one or more system clocks are disabled, the sensor panel device can periodically autonomously scan the sensor panel for touch activity. If one or more results from the autonomous scans exceed a threshold, the sensor panel device re-enables the processor and one or more clocks to actively scan the sensor panel. If the threshold is not exceeded, the sensor panel device continues to periodically autonomously scan the sensor panel without intervention from the processor. The sensor panel device can periodically perform calibration functions to account for any drift that may be present in the system.

Abstract: A method determines a type of an object in a proximity to a resonant structure having a resonant frequency as a metallic object if the object changes a phase of a power signal reflected by the resonant structure at frequencies below and above the resonant frequency. Otherwise, the method determines the type of the object as a non-metallic object.

Abstract: A circuit including a tank circuit, a pair of transistors, a bias circuit, and a capacitor. The transistors include (i) drain terminals coupled to the tank circuit, (ii) source terminals coupled to each other, and (iii) gate terminals cross-coupled to the drain terminals via a pair of capacitors. The bias circuit is coupled to the gates of the pair of transistors to i) alternatingly turn on the pair of transistors during a plurality of peaks of an oscillating signal of the tank circuit, and ii) turn off the pair of transistors during a plurality of crossing points of the oscillating signal. The capacitor is coupled to (i) the tank circuit and (ii) the pair of transistors.

Abstract: Inductive position sensing uses inductance multiplication with series connected sensor coils. In one embodiment, a first sensing domain area is established in a first target plane using first and second sensor coils disposed on a longitudinal axis, on opposite sides of the first target plane and connected in series, so that a series-combined inductance is a multiple of a sum of the respective first and second coil inductances. Target position within the first sensing domain area of the first target plane is detected based on the series-combined inductance of the first and second coils, which changes as the target moves within the first sensing domain area of the first target plane. Further sensitivity can be achieved by additional coils, series connected on the same longitudinal axis, each coil pair defining a sensing area on a respective target plane intermediate the coils.

Abstract: A buried object detector comprising: a loop antenna and an RF source, the RF source coupled to the loop antenna and arranged to feed the loop antenna with an RF signal, the detector further comprising a detector circuit coupled to the loop antenna and arranged to detect changes in the quality factor of a resonant circuit formed by the loop antenna, wherein the loop antenna is arranged to magnetically couple with a buried object, thereby reducing the quality factor of the resonant circuit.

Abstract: A self-powered switching device using a prestressed flextensional electroactive member generates a signal for activation of a latching relay. The electroactive member has a piezoelectric element with a convex and a concave face that may be compressed to generate an electrical pulse. The flextensional electroactive member and associated signal generation circuitry can be hardwired directly to the latching relay or may be coupled to a transmitter for sending an RF signal to a receiver which actuates the latching relay.