Abstract: A multi-path data dissemination method for a magnetic diffusion wireless network and a system thereof overcome environmental interferences in wireless data transmissions. Each node of the network is provided for figuring out its good neighbors by broadcasting a good-neighbor exploratory message in a bootstrap process. Each node keeps a good-neighbor table containing nodes with a RSSI higher than a threshold of the good-neighbor table. A magnetic field of a magnetic diffusion (MD) dissemination method capable of determining a data dissemination path is created according to the good-neighbor tables to ensure that the data can be forwarded to a data sink successfully.

Abstract: A circuit to detect a movement of an object provides a threshold selection module that uses one or more threshold signals identified prior to a present cycle of magnetic field signal in order to establish a threshold signal used for a present cycle of the magnetic field signal. A method associated with the circuit is also described.

Abstract: A rotation sensor includes: a magnetism generator; a sensor chip having a magneto-resistance element region and a Hall element region; and a detection circuit for detecting a relative rotation angle with reference to the magnetism generator according to output signals from each magneto-resistance element and each Hall element to detect. A phase difference is provided between output signals from the magneto-resistance elements. A phase difference is provided between output signals from the Hall elements. The magneto-resistance element region and the Hall element region at least partially overlap with each other. The detection circuit includes a comparison section, an angle computing section, and an output section. The comparison section compares an output level from each Hall element with a predetermined threshold value level, and provides a comparison result for each Hall element.

Abstract: A rotation sensor fixed to a sensor fixing member with simplified fixing system and excellent in water proofing property and vibration proofing property is provided. The rotation sensor includes a sensor unit having a magnetic sensor element for detecting rotation of a to-be-detected element provided in a rotating ring, a cable for drawing an output signal of the sensor element to the outside, and a substrate with an electroconductive region for electrically connecting the sensor element and a core line of the cable while the sensor element and the cable are fitted to the substrate. The substrate has at least one recess portion or projection portion engageable with a projection portion or recess portion in the sensor fixing member to fix the sensor unit to the sensor fixing member. A molding segment formed by molding is provided for covering the sensor unit.

Abstract: A position-sensing system magnetically senses the position of a piston rod moving with respect to a cylinder. A magnetically hard layer on the piston rod provides a recording medium. A track comprised of a plurality of magnetized regions is magnetized in the magnetically hard layer. A plurality of magnetic-field sensors is coupled to the cylinder in proximity of the magnetically hard layer to sense the magnetized track while the piston rod is moving with respect to the cylinder. A first one of the magnetic field sensors is positioned over the track to sense the magnetized regions of the track serially and a second one of the magnetic field sensors is positioned radially to one side of the track. The magnetic field sensors generate signals, in response to sensing the magnetized regions, for use in measuring rotational movement of the piston rod.

Abstract: A method and an apparatus for obtaining an equivalent circuit model of a multi-layer circuit are disclosed. The method includes simulating the multi-layer circuit using an electromagnetic field analysis to provide a coupling network; and simplifying the coupling network using a circuit model order reduction method to generate the equivalent circuit model. The method is very simple to implement and the equivalent circuit model obtained has an apparent physical meaning.

Abstract: The bearing assembly includes a rolling bearing including a rotatable raceway member and a stationary raceway member. This bearing assembly also includes a to-be-detected member carried by the raceway member and having a magnetic characteristic which cyclically varies in a direction circumferentially of the to-be-detected element and has a cycle matching with one complete rotation of the raceway member, a magnetic sensor unit carried by the raceway member in face-to-face relation with the to-be-detected member, and a magnetic detecting circuit to supply an electric power to the unit and to process an output signal from the unit to provide an output to an external circuit. The magnetic characteristic of the to-be-detected member represents a substantially sinusoidal waveform rising and falling more steeply than a sinusoidal waveform at a zero-crossing point.

Abstract: A machine having an operator interface for requesting an action from an actuator of the machine includes a movable component of the operator interface. The movable component is movable among at least two positions. One of a magnet and a Hall effect sensor is positioned to move in response to movement of the movable component. The other of the magnet and the Hall effect sensor has a stationary position relative to the movable component. A pulse width modulator is operably coupled to the Hall effect sensor for producing a first pulse width modulated signal. The first pulse width modulated signal is altered in response to movement of one of the Hall effect sensor and the magnet relative to the other. An electronic controller is in communication with the pulse width modulator and the actuator and is configured to actuate the actuator in response to evaluation of the first pulse width modulated signal.

Abstract: In the present invention, a method is provided for installing and locating a plurality of sensors distributed on a structure as part of a structural health monitoring system. The method includes verifying the proper installation of the plurality of sensors and determining the location of the plurality of sensors. In one aspect of the present invention, the step of verifying the proper installation further comprises verifying that each of the plurality of sensors are properly coupled to a sensor data collector and verifying that each of the plurality of sensors are installed in a proper location. In another aspect of the present invention, the step of determining the location of the plurality of sensors further comprises determining the positioning of each sensor in reference to fixed structures in the structure.

Abstract: A sensor system includes a sensor circuit and a plurality (e.g., N-number) of radio frequency identification (RFID) tags. The sensor circuit senses a physical parameter and supplies N-bits of digital sensor data. Each of the RFID tags at least selectively receives a digital sensor signal representative of one of the N-bits of digital sensor data and selectively transmits the digital sensor signal it received.

Abstract: A magnetostrictive-based sensor is disclosed which obtains higher return signals through the use of multiple consecutive input pulses

Abstract: An integrated angular magnetic sensor apparatus for determining a magnetic field angle within two axes of a plane is formed on a substrate onto which two anisotropic magneto-resistive sensing elements and at least one magneto-resistive sensing element are fabricated. The two anisotropic magneto-resistive sensing elements are oriented such that the output voltages of a first and second of the anisotropic magneto-resistive sensing elements are a function of a first and second trigonometric function (a sine function) of the magnetic field angle to a reference axis. The at least one magneto-resistive sensing element on the substrate and having a fixed reference magnetization oriented with respect to the reference axis such that an output voltage of the at least one magneto-resistive sensing element provides a quadrant indicator for the magnetic field angle with respect to the reference axis. The quadrant indicator is a trigonometric function such as a sine or cosine function.

Abstract: A magnetic field sensor apparatus includes a first magnetic field sensor and a second magnetic field sensor, arranged on a substrate in a spaced manner from each other, a first temperature sensor with an output for a first temperature sensor signal, a second temperature sensor with an output for a second temperature sensor signal, a first stress sensor with an output for a first stress sensor signal, and a second stress sensor with an output for a second stress sensor signal, wherein the first temperature sensor and the first stress sensor are arranged more closely to the first magnetic field sensor or at a location identical with the first magnetic field sensor, and the second temperature sensor and the second stress sensor are arranged more closely to the second magnetic field sensor than to the first magnetic field sensor or at a location identical with the second magnetic field sensor.

Abstract: A scale section is made of a magnetic material. A repeated pattern is recorded at a uniform pitch on the surface of the scale section. A sensor section is provided independently from the scale section. The sensor section is provided with a magnetic position sensor that reads the pattern, on a surface close to the surface of the scale section. Further, the sensor section is provided with a magnetic tilt sensor that detects a tilt between the surface of the scale section and the surface of the sensor section on which the position sensor is located. The magnetic position detector in which the scale section and the sensor section are separated from each other can be efficiently fixed to a detection target using the tilt sensor.

Abstract: A system and method for optimally placing radio frequency identification (RFID) antennas. The system varies the placement of RFID tag and interrogator antennas with respect to each other and a stationary object or objects. A signal generator sends a known reference signal to the one or more RFID interrogator antennas. The signal is received by the one or more RFID tag antennas and is displayed upon an oscilloscope, spectrum analyzer or other multipurpose signal measuring device. By this method, the system finds the optimal placement of the antennas with respect to each other and the object or objects.

Abstract: It is an object of the present invention to provide a non-contact rotary movement sensor capable of, by making magnetic fields from a plurality of permanent magnets not mutually affected, independently implementing an output signal and a switching signal using the same. It is another object of the present invention to provide a non-contact rotary movement sensor provided with an independent switch which outputs an output signal by using a permanent magnet and a Hall device and outputs a switching signal using a contact switch.

Abstract: A position-of-magnetic-pole detecting device includes first and second units for inferring a position of a magnetic pole. The first unit applies a current command while changing an excitation phase, infers a domain, where the position of a magnetic pole lies and which has the width thereof determined with a range of electrical angles, from the direction of rotation in which a motor rotates, and the excitation phase, and reduces the domain so as to infer the position of a magnetic pole. The second unit infers the position of a magnetic pole from a fed-back current returned responsively to a voltage command applied with the excitation phase sequentially changed. Thereafter, a voltage high enough to cause magnetic saturation is applied in order to determine the orientation of a magnetic pole, whereby the position of a magnetic pole is inferred. Although the first unit is selected, if the motor does not move due to friction or the like, the second unit is used to infer the position of a magnetic pole.

Abstract: A probe (10) for sensing movement of a body of magnetic material comprises a magnetically energisable pole piece (30), a closed loop electrical circuit (20) having a first end (25) which is wound around the pole piece (30) and forms a pole piece coil (25) inductively coupled to the pole piece, the arrangement being such that movement of a body of magnetic material (70) relative to the pole piece (30)induces a current in the closed loop circuit (20), and a second end (45), remote from the pole piece (30), which forms a transformer primary coil. A transformer secondary coil (65) is inductively coupled to the primary coil (45), and terminated by a load resistance and means for measuring an output signal from the secondary coil. The primary (45) and secondary (65) coils form a transformer such that a current in the primary coil induces a voltage across the secondary coil. One or more shorting turns (60) of a conductor are inductively coupled to the primary (45) and secondary (65) coils.

Abstract: A system and method for optimally placing radio frequency identification (RFID) antennas. The system varies the placement of RFID tag and interrogator antennas with respect to each other and a stationary object or objects. A signal generator sends a known reference signal to the one or more RFID interrogator antennas. The signal is received by the one or more RFID tag antennas and is displayed upon an oscilloscope, spectrum analyzer or other multipurpose signal measuring device. By this method, the system finds the optimal placement of the antennas with respect to each other and the object or objects.

Abstract: A strategy to control and diagnose the operation of an electric motor using a sensorless control system augmented by feedback from a position and speed sensor is disclosed. The strategy can improve the robustness of operation and diagnose potential faults in electric motors. The present invention includes a method for diagnosing operation of an electric motor and a method and system for controlling an electric motor. In the diagnostic method, a sensorless system and a sensor based system are checked against each other to determine if either of the systems is faulted. In the control method, the sensor based control system is used when the motor speed is below a predetermined threshold and the sensorless system is used when the motor speed is above the predetermined threshold. The position sensor can be a low resolution position sensor, an engine crankshaft sensor, an engine camshaft sensor, or a transmission sensor.

Abstract: A system (90) for measuring the gap (16) between a rotating blade (14) and a stationary component (12) of a turbo-machine, including an eddy current coil (30) and an eddy current tester (91). The eddy current tester may excite the coil in a pulsed eddy current testing mode. The coil is positioned in a stationary portion (12) of a turbo-machine traversed by a rotating blade and the eddy current tester is coupled to the eddy current coil to provide an indication responsive to a distance between the blade and the stationary portion as the blade traverses the position. The coil may be mounted in a frangible ceramic pill (70) movably disposed in a housing (74). The coil is positioned near the turbine blade, the coil is excited with a voltage step function (120), and the response (122) of the coil to the step function is detected and processed to determine the proximity of the blade.

Abstract: The present invention relates to a system for reliably transmitting the position of a control element to an electronic processing unit by way of electric signal lines, wherein the position signal is transmitted by way of several signal channels, and use thereof in a motor vehicle brake system. The present invention further describes a position transmitter for transmitting position signals with a magnetic encoder which is displaceable by a control element in relation to a magnetic transformer, wherein the magnetic transformer(s) along with an integrated electronic signal-conditioning circuit are arranged in an electronic sensor subassembly, as well as a receiving device for receiving a position signal comprising several processing channels for processing the position signals of the position transmitter.

Abstract: A sensor assembly for sensing angular position of one object relative to another object. A capacitor is formed between a transmitter capacitor plate having a pair of transmitter electrodes and a receiver capacitor plate having preferably eight receiver electrodes forming four receiver electrode pairs. A dielectric rotor rotates between the plates, the rotor having first and second segments each subtending 67.5 which are mutually separated by a vacancy subtending 45 degrees, and further having a third segment subtending 45 degrees disposed between the first and second segments diametrically opposite the vacancy. An electrical circuit measures net charge induced on each of the receiver electrode pairs, wherein the charges indicate the angular position of said rotor relative to said transmitter and receiver capacitor plates.

Abstract: A strategy to control and diagnose the operation of an electric motor using a sensorless control system augmented by feedback from a position and speed sensor is disclosed. The strategy can improve the robustness of operation and diagnose potential faults in electric motors. The present invention includes a method for diagnosing operation of an electric motor and a method and system for controlling an electric motor. In the diagnostic method, a sensorless system and a sensor based system are checked against each other to determine if either of the systems is faulted. In the control method, the sensor based control system is used when the motor speed is below a predetermined threshold and the sensorless system is used when the motor speed is above the predetermined threshold. The position sensor can be a low resolution position sensor, an engine crankshaft sensor, an engine camshaft sensor, or a transmission sensor.

Abstract: By combining outputs from a Hall sensor and a magnetoresistive (MR) sensor, a 360-degree rotary position sensor can be achieved. The Hall sensor and the MR sensor both detect a magnetic field produced by a magnet. The Hall sensor detects the polarity of the magnetic field, while the MR sensor detects the angular position of the magnetic field, up to 180-degrees. With a positive output from the Hall sensor, the first 180-degrees of the angular position is detected. With a negative output from the Hall sensor, the second 180-degrees of the angular position is detected.

Abstract: An apparatus and method for measuring changes in pressure, temperature, speed, acceleration, vibration, or volume by detecting variations in one or more electrical circuits as the distance among a plurality of electrically conductive and magnetically permeable components changes. The invention utilizes changes in properties of electrical circuits induced by the variations in the intensity of a magnetic flux field resulting from spatial movements or displacement of the components. The components that make up the sensor may be electrically insulated from the electrical circuit that is the source of the magnetic flux field and detects the change and analyzes it as a measured change in pressure, temperature, speed, acceleration, vibration, volume, etc.

Abstract: A microelectromechanical systems (MEMS) Device manufactured on a microscopic scale using integrated circuit techniques provides a sensitive magnetic field sensor by detecting motion caused by the Lorentz force produced by a current through a MEMS conductor. The resulting MEMS may be used as a component in a variety of devices including current sensors and proximity sensors.

Abstract: A proximity probe including an encapsulated proximity probe tip manufactured by locating a support pin within an interior cavity of a coil and preform assembly and cantilevering an end of the support pin between two mold plates for supporting the assembly within a mold cavity defined by the mold plates and injecting moldable material into the cavity for molding an encapsulation of material over the assembly wherein the encapsulated assembly defines an encapsulated probe tip connectable to any cable length. The preform includes a hollow annular recess skirting a centering bore for tuning the coil and centering the coil onto the preform. The probe further includes a casing circumscribing the encapsulated probe tip and having an opening disposed therein such that when heat is applied to the casing a portion of the underlying encapsulation is melted and dispensed into the opening for interlocking the casing to the encapsulation.

Abstract: The invention relates to a device for detecting the position of a magnet which is positioned so that it is moveable (3, 23, 24) to produce a magnetic field (6) through a ferromagnetic wall (1, 29), a magnetic field sensor (10, 21, 21′) being situated in front of said wall. When said magnet (3, 23, 24) is moved in relation to said wall (1), the lines (6) of the field build up a useful flux (6) which progresses in said wall (1, 29). Said useful flux has magnetic remanence (7) which is retained after the magnet (3, 23, 24) has passed by, is aligned along the movement axis of the magnet (3, 23, 24) in accordance with the polarity, and builds up a fringing flux (12) to the front side of the wall (1, 29) where the magnetic field sensor (10, 21, 21′) is positioned. Outside of said wall, the fringing flux (12) is opposed and is aligned with the useful flux (6).

Abstract: A magnetic object tracking algorithm, that may be implemented as an apparatus or a method, that permits kinematic tracking of magnetized objects, or targets, using magnetic field strength measurements derived from one or more vector magnetometers. The magnetic object tracking algorithm effectively tracks a maneuvering magnetic dipole target using an extended Kalman filter directly observing (processing) real magnetic field strength data.