Abstract: A digital eddy current proximity system including a digital impedance measuring device for digitally measuring the proximity probes impedance correlative to displacement motion and position of a metallic target object being monitored. The system further including a cable-length calibration method, an automatic material identification and calibration method, a material insensitive method, an inductive ratio method and advanced sensing characteristics.

Abstract: To provide a method for checking bores in or edges on an object of measurement, and, in particular, for recognizing burrs, by means of which bores can be checked in a simple and accurate way, it is proposed that a prepared object of reference be scanned by a distance sensor and in correlation therewith the object of measurement be scanned by a further distance sensor and a comparison be made of the measurement signals of the two distance sensors.

Abstract: A digital eddy current proximity system including a digital impedance measuring device for digitally measuring the proximity probes impedance correlative to displacement motion and position of a metallic target object being monitored. The system further including a cable-length calibration method, an automatic material identification and calibration method, a material insensitive method, an inductive ratio method and advanced sensing characteristics.

Abstract: A system that remotely measures displacement between two objects. A passive sensor is affixed between the objects. The internal sensor uses magnetic coupling between two sensor elements to measure their relative displacement. The sensors are either a) a permeable rod and a complimentary coil in parallel with a tuning capacitor; or b) two permeable rods, each having its own surrounding coil and a tuning capacitor. One of the sensor elements is affixed to each object which is to be monitored. When an interrogating device is placed near the sensors, a resonance can be measured whose frequency characteristics change in a reproducible manner with the relative displacement of the sensors. The resulting resonance characteristics can be calibrated in such a way as to enable the displacement of the objects to be determined.

Abstract: A method and apparatus for electromagnetic navigation of a surgical probe near a metal object. The electromagnetic navigation system includes a transmitter coil array and a shield. The transmitter coil array has a plurality of transmitter coils and is operable to generate the electromagnetic field to navigate the probe. The shield is positioned adjacent the metal object and is operable to shield the metal object from the electromagnetic field generated by the transmitter coil array, such that the shield substantially reduces distortion of the electromagnetic field by the metal object.

Abstract: A system for calculating magnetic stray field data for current loop configurations. A graphical user interface utilizes multiple screens to define a current loop configuration, and prompt a user to select i) one of three orthogonal dipole directions in which the current loop configuration is aligned, ii) units of measure associated with the current loop configuration, and iii) one of a plurality of calculation scenarios. Calculation scenarios include i) current loop configuration defined by a single-size current loop, ii) current loop configuration defined by a non-uniform sized current loop, and current loop configuration defined as a single-size current loop and the user selects direction of simulated movement, start and stop positions along the movement direction and a step increment. A processor coupled to the graphipal user interface is programmed to perform magnetic stray field calculations for the selected calculation scenario. Calculations are displayed in graphical formats chosen by the user.

Abstract: Method for determining the position or the orientation of an object using a magnetic field and corresponding device.

Abstract: Two A.C. output signals amplitude-modulated in accordance with two function values (sine and cosine) differing from each other in correspondence to a position-to-be-detected are received from a position sensor such as a resolver. By performing an addition or subtraction between a signal derived by shifting the electric phase of one of the received A.C. output signals by a predetermined angle, and the other received signal, two electric A.C. signals (sin(&ohgr;t±d+&thgr;), sin((&ohgr;t±d−&thgr;)) are electrically synthesized which have electric phase angles (&thgr;) corresponding to the position-to-be-detected and are phase-shifted in opposite directions. “±d” here represents phase variation error caused by factors, other than the position-to-be-detected, such as temperature change.

Abstract: An encoder made of rubber material in which the S-poles and the N-poles are alternately magnetized in circumference, whose magnetic force is strong and whose variation of the magnetic force is slight in the circumferential direction when it is magnetized. And a manufacturing method thereof. A ring shaped rubber compound made of unvulcanized rubber material into which magnetic powders are mixed and having thickness t1 of 1.5 times to 5 times thicker than the thickness t of the encoder made of rubber material as the final product is vulcanizingly molded. In this vulcanizingly molding process, the thickness of ring shaped rubber compound is reduced to one fifth (⅕) to two thirds (⅔) by compressing the ring shaped rubber compound in the axial direction under high temperature. And then, vulcanizingly molded one is magnetized S-poles and N-poles alternately in circumference.

Abstract: An evolutionary program is used to calibrate a ship degaussing system with respect to one or more parameters relating to the ship's magnetic signature. Pursuant to the computer program, a mathematical vector lists electrical current values which correlate with the degaussing coils. A genetic algorithm is executed through a certain number of generational iterations in order to find a solution vector which will optimize the parameter(s). Every generational population has the same number of vectors. An initial population is randomly engendered, and successive populations are engendered through a biasedly random process wherein each vector has associated therewith a parenthood selection probability which is commensurate with its fitness. The offspring vectors are given birth to via crossover hybridization of parent vectors, and a small fraction of offspring vectors are randomly modified via mutation. The present invention is suitable for accomplishing optimization (e.g.

Abstract: A sensor attachment structure is provided with grooves for attaching, to an actuator body, magnetism-detecting sensors each of which is constructed to have a substantially rectangular cross section. The groove is designed to have a substantially rectangular open cross section. The groove includes a tapered section which has widths gradually narrowed inwardly from the contour surface, and a spread section which is spread from narrow width ends of the tapered section and to which pawls of the magnetism-detecting sensor are installed.

Abstract: A retrofittable valve monitor provides an input to an electrical circuit to indicate a fully closed position of a ball valve. A magnetically permeable object attached to the ball valve lever handle actuates a magnetic reed switch in a proximity sensor when the ball valve is moved to the fully closed position. A bracket which fits between the ball valve body and the ball valve lever handle is held in place by the ball valve locking nut so the proximity sensor is held in proper alignment to be actuated by the magnetically permeable object. The actuated reed switch provides an input to a switched electrical circuit.

Abstract: A method of navigating a magnet-tipped distal end of an elongate medical device through the body includes providing an image display of the part of the body through which the medical device is being navigated and using the display to input the desired path of the medical device by identifying points on the desired path on the display. The magnetic field needed to orient the end of the medical device in the direction of the desired path as indicated on the display is then determined. In one embodiment where only points on the desired path are identified, the field direction is the direction indicated by the points on the desired path.

Abstract: A position detecting apparatus includes: a position sensor 10 that inputs an excitation signal having a given period waveform and outputs a first amplitude modified signal induced in accordance with a detected position from a first output winding and outputs a second amplitude modified signal induced in accordance with a detected position from a second output winding; a first phase shifting circuit 23 for electrically shifting a phase of the first amplitude modified signal by a given angle; a second phase shifting circuit 24 for electrically shifting a phase of the second amplitude modified signal by a given angle; converting means 15,16 for converting the signal outputted from the first phase shifting circuit 23 and the signal outputted from the second phase shifting circuit 24 into a phase modulated signal; and calculating means 17-22 for obtaining a detected position on the basis of the phase of the phase modulated signal outputted from the converting means 15,16.

Abstract: Methods and apparatus are provided for locating the position, preferably in three dimensions, of a sensor by generating magnetic fields which are detected at the sensor. The magnetic fields are generated from a plurality of locations and, in one embodiment of the invention, enable both the orientation and location of a single coils sensor to be determined. The present invention thus finds application in many areas where the use of prior art sensors comprising two or more mutually perpendicular coils is inappropriate.

Abstract: A motion detector comprising a rotator member having at least one radially positioned member and being mounted for rotation from at least a first position to at least a second position; a detector member, preferably a Hall Effect sensor; and a magnet producing a magnetic field; wherein, the radially positioned member is characterized by altering the magnetic flux of the magnetic field when it moves into and out of proximity to the magnet; and wherein the detector member detects the alteration of the magnetic flux. The motion detector is preferably used to detect the speed, type, position, presence, and absence of a printer ribbon cartridge.

Abstract: A system and method for localizing an in vivo signal source using a wearable antenna array having at least two antenna elements. The signal is received and a signal strength is measured at two or more antenna elements. An estimated coordinate set is derived from the signal strength measurements.

Abstract: First A.C. output signal sin(&ohgr;+&thgr;) having an electric phase angle shifted in a positive direction in accordance with a position-to-be-detected is produced along with a second A.C. output signal sin(&ohgr;−&thgr;) having an electric phase angle shifted in a negative direction. First and second detection data are generated by detecting respective phase differences (+&thgr; and −&thgr;) of the first and second A.C. output signals from a predetermined reference phase. First predicted value is provided on the basis of at least two successive samples of the first detection data, and a second predicted value is provided on the basis of at least two successive samples of the second detection data. The first and second predicted values are modified to provide a standard predicted value for correcting a nonlinear error resulting from the Doppler effect.

Abstract: The invention relates to a method of a continuous determination of an instantaneous position of an impeller blade tip (5′) in a rotor turbine machine, particularly in a turbine impeller (6) in a turbojet engine during its operation in a real condition in order to obtain a current information on a technical state of the blade (5). In a selected place of an housing (7) of a rotor turbo machine, in a movement plane of impeller blade tips (5′), it is arranged in a stable manner at least one microwave antenna (3) with an aperture shape (4) which is consistent with an internal surface of an housing (7). The microwave signal (11), which is produced by a microwave homodyne system, is emitted, and then received, through a microwave antenna (3). The output signal (9) from that system, which carries out information on each instantaneous position of an impeller blade tip (5′) in relation to an antenna aperture (4), is converted by an electronic system, and then it is read.

Abstract: A flexible probe is provided for detecting time-varying magnetic fields produced in an electric generator. The flexible probe is adapted to be disposed within an air gap formed between an iron stator and a rotatable rotor. An electrostatic shield layer is formed on a front face of the probe and a printed circuit forming at least one coil is printed on the back face. When the flexible probe is used for detecting time-varying magnetic fields, a voltage is induced in the coil when the coil is exposed to a time-varying magnetic field.

Abstract: The invention discloses a low profile input device for moving a cursor, scrolling a page, or selecting a function on a display of a handheld device. In an embodiment of the invention, a planar joystick (402,940) for use moving a cursor on the display of a handheld device comprises a movable sliding button having a first magnet M1 embedded therein. The button is slid by a user's finger over a second magnet M2, an action that distorts the magnetic flux 418 which is detected by a plurality of magnetic flux sensors 420. The direction and magnitude of the cursor movement on the display correspond to the change in flux caused by the movement of the sliding button.

Abstract: A force sensor (50, 50′, 50a) generates a signal indicating the usage of a seat belt. A cylindrical housing (70, 70′) has a wall (72) and a bottom (74) which define an internal cavity (124). The bottom has an opening (76) through it. A cable anchor (90) is slidably received within the cavity and is connected to a cable (54). The cable has one end secured to the cable anchor and another end connected to an anchor point. A magnet (120) is connected to a top of the cable anchor and is movable with the cable anchor. The cable anchor is biased to resist motion of the cable anchor toward the bottom of the housing. A magnetic sensor (200) for generates a signal indicative of the distance between it and the magnet. A sensor housing (180) is connected to the housing and is positioned on the housing to position the magnetic sensor a determinable distance from the magnet at a null position. A housing end cap (150) is secured to the housing for enclosing an open end of the housing.

Abstract: A digital eddy current proximity system including a digital impedance measuring device for digitally measuring the proximity probes impedance correlative to displacement motion and position of a metallic target object being monitored. The system further including a cable-length calibration method, an automatic material identification and calibration method, a material insensitive method, an inductive ratio method and advanced sensing characteristics.

Abstract: An accelerator position sensor urges a rotary member 2into rotation relative to a fixed member 1 fixed on the side of a vehicle body in a direction of a returning operation of an accelerator pedal by torque of a torsion spring 3, and detects the angle of rotation of the rotary member 2 in a sensor unit 4 thereof. In the accelerator position sensor, a cylindrical resin member 6 is disposed between a boss 1a of the fixed member 1 and the torsion spring 3 so as to be pressed against the boss 1a by a reaction of the torque of the torsion spring 3 to create sliding resistance to the boss 1a during rotation of the rotary member 2, in order that the pressing force characteristic of the accelerator pedal exhibits sufficient hysteresis between pressing and returning operations.

Abstract: A monitor, shutoff control, and alarm for use with an inlet water supply obtained from a municipal water supply to prevent excessive usage of water due to leakage or human error, that includes a measuring means and shutoff valve connected to the inlet supply, a processor that includes a program for setting threshold values of water volume per unit time anticipated by the particular household, which, when exceeded, will set off an audio alarm or will activate a telephone dialer to call a predetermined number if no one is at home. The system is programmed in volume increments of time, such as hours, days, or weeks, to accommodate systems that include sprinklers which may require some volume of water over a short period of time. The system can be portable. It is easily installed and mounted in conventional water systems for homes, but can be individually adjusted based on the anticipated water usage of a particular household.

Abstract: A pedal stroke sensor a rotor that rotates with a brake pedal with a pair of brushes fixed on the rotor. The brushes are inclined oppositely to each other along rotating direction of the rotor and contact a circuit printed on a circuit board to generate output voltages V1A and V1B which increase and decrease oppositely to each other in response to the brushes sliding over the circuit board. A difference signal |V1A−V1B| is output as a signal corresponding to pedal stroke S of the brake pedal. When any kind of vibration changes the contacting positions of the brushes on the board, the output voltages V1A, V1B change in the same direction, so that, even if the contacting positions of the brushes change because of a vibration, the difference signal |V1A−V1B| does not change greatly, allowing accurate detection of the position of the brake pedal even if such vibrations occur.

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.

Abstract: A magnetic detector to detect a magnetic object's rotation and movement using a magnetoresistive element having hysteresis. The magnetoresistive element is set so as to tilt from the magnetizing direction of a magnet up to a predetermined angle &thgr; between the rotational magnetic object to be detected and the magnet. The magnetic detector provides a high accuracy signal that corresponds to the distance between the rotational magnetic object to be detected and the magnetoresistive element. The signal obtained is independent of the rotational direction or rotational speed of the magnetic object to be detected or the atmospheric temperature of an apparatus. Moreover, the temperature dependency of the output signal (amplitude) of the magnetoresistive element is decreased.

Abstract: A circuit and apparatus for magnetically sensing fluid flow and applying voltage to a load has a spring loaded check valve disposed within a conduit and provided with a magnetic shield. A magnet is located on one side of the magnetic shield while a sensor, associated with the valve, is located on the opposite side of the magnetic shield. The check valve, and hence the magnetic shield, moves to permit fluid flow. When the magnetic shield moves due to fluid flow, the magnet activates the sensor. A load control circuit includes a supply terminal for receiving a supply voltage and a detector which detects a condition requiring the operation of a load. The detector causes a threshold voltage to be generated from the supply voltage, and a time delay controller controls the time required to generate the threshold voltage.

Abstract: An encoder comprises position detecting device for detecting a magnetic pole position and a rotational position of a motor. The encoder also includes a memory portion for storing parameter information particular to the motor or the position detecting device. A transmitting portion of the encoder is provided for externally transmitting parameter information particular to the position detecting device as a differential signal. A transmission suspension request detecting device is provided for detecting that the differential signal is driven by a given signal externally provided such that the differential signal does not exist as a transmission signal and for generating a transmission suspension request signal requesting suspension of transmission of the differential signal.

Abstract: The present invention provides an apparatus and a method for determining the position of a first element relative to a second element. The apparatus includes a magnet being attached to the first element. First and second sensing devices are adapted to detect a magnetic flux density produced by the magnet and responsively generating first and second signals. The apparatus also includes a controller for receiving the first and second signals and responsively determining the position of the first element relative to the second. The present invention enables continuous calibration during the normal operation of the machine.