Abstract: A micromobility transit vehicle may include a wheel, a dynamo, a control module, and a battery. The dynamo may be associated with the wheel and configured to transmit a first signal based at least on a detection of one or more movements of the wheel that meets or exceeds a threshold movement of the wheel. The control module may be configured to receive the first signal transmitted by the dynamo. The control module may be configured to transmit a second signal upon receiving the first signal from the dynamo. The battery may be configured to receive the second signal transmitted by the control module. The second signal may cause the battery to wake from a battery-off state to a battery-on state.

Abstract: An apparatus and a method provide an output signal indicative of a speed of rotation and/or a direction of movement of a ferromagnetic object having ferromagnetic features and capable of moving. A variety of signal formats of the output signal are described, each of which have pulses at a rate faster than the ferromagnetic features pass by the magnetic field sensor. The magnetic field sensor includes a plurality of diagnostic circuits that detect a failure of the magnetic field sensor and output a diagnostic signal indicative of the failure. The controller can receive the diagnostic signals and generate a sensor output signal including a failure state to indicate the detected failure.

Abstract: A magnetic circuit may include a magnetic sensor. The magnetic sensor may determine an adjustment factor associated with calculating a variable switching threshold. The variable switching threshold may be a configurable switching threshold based on which the magnetic sensor provides outputs associated with a speed signal corresponding to a rotation of a tooth wheel. The magnetic sensor may provide an output, associated with the speed signal, based on the variable switching threshold.

Abstract: An apparatus for converting mechanical energy into electrical energy includes a rotor having a first end portion and a second end portion, a first stator including a plurality of magnet poles, and a second stator including a plurality of magnet poles. The rotor is located about a shaft along a rotational axis. The rotor includes a plurality of north and south poles alternating along a circumference of the rotor. The plurality of magnet poles of the first stator are rotated 180 electrical degrees with respect to the plurality of magnet poles of the second stator.

Abstract: A speedometer system is disclosed that replaces reliance on the feedback from a vehicle transmission and instead tracks the vehicle speed from an external source. In some embodiments, a global positioning unit (GPS) is connected to a microcontroller that drives an electric motor to turn and display a speed for an improved speedometer reading. The speedometer system further including a calibration unit that allows for the manipulation of the electric motor to display a predetermined calibration speed on the speedometer.

Abstract: Embodiments of the disclosure provide a current sensor including a conductive element and at least two magnetic field sensors. The conductive element includes at least three separate terminal areas, a common conductive area and at least three separate intermediate areas connecting the respective separate terminal areas to the common conductive area. Each of the terminal areas is connected separately via a respective separate intermediate area of the at least three separate intermediate areas to the common conductive area to guide a current applied to the respective terminal area into the common conductive area. The at least two magnetic field sensors are arranged at different geometric positions adjacent to the at least three separate intermediate areas, wherein each of the magnetic field sensors is configured to sense a magnetic field component of each current flowing into the common conductive area to provide a sensor signal based thereon.

Abstract: A bicycle rotation detecting device is provided with a first electrical connector, a second electrical connector, a rotation detecting circuit and an output part. The second electrical connector is electrically connected to the first electrical connector by an electrical path. The rotation detecting circuit detects a waveform of alternating current in the electrical path and produces a rotation detection signal. The output part is electrically connected to the rotation detecting circuit. The output part outputs either the rotation detection signal of the rotation detecting circuit or a signal based on the rotation detection signal of the rotation detecting circuit.

Abstract: In some aspects of what is described herein, an aircraft wheel speed sensor system includes a pair of conductors coupled between an electro-mechanical system and a control system. The control system is configured to apply a carrier voltage signal to the pair of conductors and to detect a modulated current signal on the pair of conductors. The electro-mechanical system includes a stator and a rotor that moves upon rotation of an aircraft wheel. The stator includes a winding disposed about the rotor. The winding is configured to produce the modulated current signal on the pair of conductors in response to movement of the rotor. The modulated current signal has a frequency that is dependent on a rotational speed of the aircraft wheel.

Abstract: The motor speed detection apparatus detects rotational speed of a motor. The apparatus includes an FG coil (21) and a magnet (22) to be relatively moved with rotation of the motor, the FG coil outputting an alternating-current signal to be sampled by the apparatus, an A/D converter (1) to convert the alternating-current signal into a digital signal, an integrator (2) to perform time integration on the digital signal, a first determiner (3, 9) to determine which one of plural threshold ranges includes an integration value obtained by the integrator, a second determiner (3, 8) to determine whether change of the integration value is increase or decrease, and a logical product calculator (3, 10) to produce a binary signal showing a logical product of determination results of the first and second determiners. The apparatus calculates the rotational speed based on a production cycle of the binary signal.

Abstract: A management apparatus is described of a rotating motor and a load during power loss; the apparatus comprises a first switching circuit coupled with the rotating motor and a controller of said first switching circuit. The controller is configured to drive the first switching circuit so as to convert a back-electromotive force voltage developed in the rotating motor into a power supply voltage for the load. The first switching circuit is driven in accordance with a first duty cycle. The apparatus comprises a second switching circuit coupled with the load and driven in accordance with a second duty cycle. The controller is configured to vary said first and said second duty cycles to keep the power supply voltage for the load above or equal to a threshold voltage.

Abstract: A bicycle rotation detecting device is provided with a first electrical connector, a second electrical connector, a rotation detecting circuit and an output part. The second electrical connector is electrically connected to the first electrical connector by an electrical path. The rotation detecting circuit detects a waveform of alternating current in the electrical path and produces a rotation detection signal. The output part is electrically connected to the rotation detecting circuit. The output part outputs either the rotation detection signal of the rotation detecting circuit or a signal based on the rotation detection signal of the rotation detecting circuit.

Abstract: A control system for use in safety critical human/machine control interfaces is described, more particularly a joystick type control system and particularly a joystick type control system utilizing magnetic positional sensing. The control system provides a control input device having a movable magnet, a pole-piece frame arrangement positioned about the magnet, at least three magnetic flux sensors being positioned in said pole-piece frame arrangement and a monitoring arrangement for monitoring the output signal of each of said at least three sensors.

Abstract: The present embodiments provide an acceleration sensor, which enables highly accurate detection and has an extremely compact size. The acceleration sensor of the present embodiments is provided with a substrate, a anchor portion formed on the substrate, a support beam, which has one end connected to the anchor portion and extends across a space from the substrate, and a proof mass which is connected to the other end of the support beam and held across a space from the substrate. The acceleration sensor is further provided with first and second piezoelectric bending resonators, a comparison unit, and a calculation unit. The first and second piezoelectric bending resonators have one end connected to the anchor portion and the other end connected to the proof mass or the support beam and have a stack of a first electrode, a first piezoelectric film, and a second electrode.

Abstract: A fan speed detection circuit includes a counter, an integrating circuit, a current regulation circuit, a connector and a matching circuit. The connector electrically connects to the current regulation circuit and a fan. The counter outputs a pulse signal, the integrating circuit receives the pulse signal from the counter, and converts the pulse signal from the counter into a corresponding analog command signal. The current regulation circuit adjusts the current from the integrating circuit according to the command signal and outputs the adjusted current to the connector. The matching circuit converts the voltage from the connector and provides a suitable voltage for activating the counter to enable the counter to detect and quantify and record the rotation speed of the fan in all circumstances.

Abstract: This invention relates to an apparatus and method for deriving speed and position information for an electric motor. Apparatus for and a method of controlling a motor 100 are also disclosed. The apparatus for providing information relating to the operation of an electrical motor 100 comprises a sampler 50, 51 for sampling the instantaneous motor current is and a processor 160 for determining the instantaneous rate of change of the motor current and providing information about the motion or position of said motor based on said instantaneous rate of change of the motor current. In this way speed and position information can be provided, at low speeds, and without using a speed sensor.

Abstract: A device for determining the rotational speed of a transmission shaft (12). The device includes a rotational speed indicator (3) connected, in a rotationally fixed manner, to the transmission shaft (12) and at least one rotation speed sensor (2) including at least one sensor element (10). By way of the sensor element (10), the speed of the transmission shaft (12) is detected via the speed indicator (3). The speed sensor (2) is attached to a shifting element (5) for actuating a sliding sleeve (4) of a clutch device (1) that is connected to the transmission shaft (12) in such a manner that the sliding sleeve (4) axially movable on but fixed so as not to rotate.

Abstract: A method for developing software as a layered, segmented system having diverse functionalities, based on a software architecture and an aerial vehicle utilizing the software architecture are provided. The software architecture for the aerial vehicle, such as an unmanned aerial vehicle (UAV) includes an electrical segment, a propulsion segment, a flight management segment, a navigation segment, a data link segment, and perhaps a payload segment. Each segment includes a number of software modules and objects, and each segment interfaces with or controls one or more devices. The software architecture also includes a number of layers, including an executive layer for managing execution rates of the segments, a vehicle controller layer for coordinating activities across segments, and various layers providing utilities, common services, and computing support including operating system support. Rules of engagement guiding interaction between software entities within the software architecture are specified.

Abstract: A method and apparatus to dynamically and adaptively demodulate induction motor instantaneous rotor slot harmonic frequency for line-connected squirrel-cage polyphase induction motors. The instantaneous rotor slot harmonic frequency carries essential information on the instantaneous rotor speed. Based on a correlation between the motor's input power and its rotor slot harmonic frequency, a dynamically varying carrier frequency is computed and used in a rotor slot harmonic frequency detector. The rotor slot harmonic frequency detector is based on a superheterodyne principle. It contains a generalized linear-phase low-pass filter, whose bandwidth is estimated dynamically by a filter bandwidth estimator. The rotor slot harmonic frequency detector also includes a latency compensator, which receives the dynamically varying carrier frequency signal and synchronizes it with the output of a frequency demodulator.

Abstract: An apparatus for measuring linear velocity of a movable element relative to a stationary element includes a magnetic element fixed in relation to the stationary element. A soft-magnetic yoke is fixed in relation to the movable element to move with the movable element and is in non-contact relation with the magnetic element. A yoke pole is positioned proximate to the magnetic element and spaced therefrom by an air gap. The pole is magnetically coupled to the magnetic element so that a magnetic flux is generated in the air gap substantially orthogonal to the axis of motion. A conductive coil is coiled around a coil axis and is fixed in relation to the stationary element with the coil axis substantially parallel to the axis of movement. The coil is in non-contact relation with the yoke and resides between the magnetic element and the pole of the yoke in the magnetic flux.

Abstract: An angular position sensor and method that relies on a stationary circular array of Hall sensors and a rotatable circular array of magnets arranged about a common axis. A periodic and simultaneous reading of all of the Hall sensor outputs is used to determine angular velocity.

Abstract: A control device for a travel motor mounted to a vehicle has a resolver which works as a rotation-angle sensor. The control device has a RDC which calculates a rotation-angle output value ? based on rotation detection signals Sa, Sb transferred from the resolver. The control device supplies electric power to the travel motor based on the rotation angle output value ?. The RDC calculates “sin(???)” as an error deviation ? based on the signals Sa and Sb and the rotation-angle output value ?. The RDC calculates an angular acceleration by multiplying the error deviation ? with a gain (=Ka·Kb), and integrates the angular acceleration two times in order to obtain a next rotation-angle output value. A gain control part of the RDC decreases the gain when the judgment means judges that the travel motor rotates at a constant rotation speed.

Abstract: An indicating instrument for a vehicle includes a step motor including a field winding, a pointer, a stopper device for stopping the pointer, which is rotating in a zero-reset direction, at a stopper position, a detecting device for detecting induced voltage of the field winding at each of detecting points, a control device for performing zero-reset control, whereby a drive signal is controlled to rotate the pointer in the zero-reset direction. In a state of abnormal detection in which the induced voltage larger than a predetermined set value is detected at a zero point; and the induced voltage equal to or smaller than the set value is detected at a next detecting point to the zero point, the control device assumes synchronization loss of the step motor and continues the zero-reset control until an assumptive electrical angle corresponding to a rotational position of the pointer reaches the zero point.

Abstract: An indicating instrument includes a step motor having a field winding, a pointer, a reduction gear mechanism having gears, a stopper device for stopping the pointer at a stopper position, a detecting device for detecting induced voltage of the winding at each of detecting points that include a zero point corresponding to the stopper position, a control device for controlling a drive signal, and an updating device for updating the zero point based on the induced voltage during zero-reset control performed by the control device. The control device performs return control, whereby the pointer rotates to a return point in an indication value increasing direction and then returns to a waiting point in a zero-reset direction to stand by at the waiting point, prior to zero-reset control, whereby the pointer rotates from the waiting point in the zero-reset direction.

Abstract: The present invention provides a motor drive apparatus which improves a trade-off relation between a stable position detection and noise at its driving. A sensorless drive operation circuit calculates by operation a zero cross point (point p) of a voltage of a position detection phase at the next interval, using time information measured based on an output signal from a comparison circuit at the previous interval and the present interval. After the point p has been calculated, points a and b are detected by interrupting a predetermined time drive current.

Abstract: An integrated circuit for controlling a DC motor is disclosed. The integrated circuit includes at least one digital position and speed circuit (DPS) for providing measurements of speed, position, and direction of the motor, the DPS being in signal communication with the motor for receiving a pair of signals having a quadrature relationship; and at least one programmable gain amplifier (PGA) electrically coupled to the motor, the PGA being configured to receive a feedback signal indicative of current flowing through the motor and to apply a second signal to the motor for adjusting the speed of the motor; and at least two analog-to-digital converters (A/D), one A/D being used to quantize the output of the PGA for an off-chip processor; and another A/D to provide motor reference position from an analog sensor, such as a potentiometer; and at least two digital-to-analog converters (D/A), one D/A used to set the motor voltage; and another D/A used to set the motor current limit.

Abstract: An apparatus for measuring linear velocity of a movable element relative to a stationary element includes a magnetic element fixed in relation to the stationary element. A soft-magnetic yoke is fixed in relation to the movable element to move with the movable element and is in non-contact relation with the magnetic element. A yoke pole is positioned proximate to the magnetic element and spaced therefrom by an air gap. The pole is magnetically coupled to the magnetic element so that a magnetic flux is generated in the air gap substantially orthogonal to the axis of motion. A conductive coil is coiled around a coil axis and is fixed in relation to the stationary element with the coil axis substantially parallel to the axis of movement. The coil is in non-contact relation with the yoke and resides between the magnetic element and the pole of the yoke in the magnetic flux.

Abstract: A sensor package apparatus includes a lead frame substrate that supports one or more electrical components, which are connected to and located on the lead frame substrate. A plurality of wire bonds are also provided, which electrically connect the electrical components to the lead frame substrate, wherein the lead frame substrate is encapsulated by a thermoset plastic to protect the plurality of wire bonds and at least one electrical component, thereby providing a sensor package apparatus comprising the lead frame substrate, the electrical component(s), and the wire bonds, while eliminating a need for a Printed Circuit Board (PCB) or a ceramic substrate in place of the lead frame substrate as a part of the sensor package apparatus. A conductive epoxy can also be provided for maintaining a connection of the electrical component(s) to the lead frame substrate. The electrical components can constitute, for example, an IC chip and/or a sensing element (e.g., a magnetoresistive component) or sense die.

Abstract: A method and a device for measuring the speed of a pulse-activated electric motor are described. According to this method, the motor is fully activated at time intervals to be determined for a defined measuring time by the circuit element provided for timing and, in this time, the frequency of the current ripples, which is proportional to the motor speed, is measured. A current-proportional voltage measuring device is located on the circuit element, on whose load side are located an amplifier, filters, and an evaluation circuit in the form of a comparator for determining the frequency of the current ripples flowing in a measured phase during which the motor is fully activated.

Abstract: A removable sensor assembly for non-intrusively sensing instantaneous speed of an engine comprising a crankshaft having a respective end equipped with an externally accessible bolt, the removable sensor assembly comprising: a housing comprising a recess configured to removably receive and engage a portion of the externally accessible bolt; and a force sensing device received in the housing, the force sensing device being configured to wirelessly provide information indicative of angular motion of the crankshaft, the force sensing device comprising: at least one coil; a power supply for providing an excitation to the coil, wherein the coil provides a first signal and a second signal each corresponding to the movement of the housing, the first signal corresponding to the resistance of the coil and the second signal corresponding to the inductance of the coil; and a signal transmitter coupled to the coil to receive and transmit the first signal and the second signal.

Abstract: A method and apparatus for determining the velocity of a rotating device is described herein. The apparatus includes a magnet assembly affixed to a rotating shaft of a rotating device and a circuit assembly. The circuit assembly includes a circuit interconnection having a sense coil and sensors affixed thereto. The circuit assembly is adapted to be in proximity to the magnet assembly, wherein the magnet assembly combines with the circuit assembly to form an air core electric machine such that voltages generated from the sense coil exhibits an amplitude proportional to the velocity.

Abstract: An apparatus and method for measuring a characteristic of a machine. A variable reluctance sensor (VRS) is coupled to the machine. A first switching device and capacitor, coupled in parallel with the VRS, boosts a variable amplitude of a basic output signal generated by the VRS to increase the signal-to-noise ratio. A control input of the first switching device receives signals, and a modified output signal is generated by the first switching device, having a variable amplitude that is substantially higher than the variable amplitude of the VRS. The modified output signal has an increased signal-to-noise ratio such that machine speed can be more accurately measured during a start-up phase.

Abstract: Linear velocity sensor and method for reducing non-linearity in the output signal of the sensor are provided. The sensor comprises a ferromagnetic housing including an opening. The sensor further comprises a spool disposed in the housing. The spool includes a bore for receiving a slidable ferromagnetic rod. The ferromagnetic rod may be extendable through the opening in the housing. A magnet is mounted at the one end of the rod distal from the opening when the rod is substantially inserted in the bore. A coil is wound on the spool. The number of turns of the coil is arranged to taperingly increase as the coil progresses from an end of the spool proximate the opening in the housing to the opposite end of the spool. The tapering arrangement for the number of turns of the coil is selected to reduce non-linearity of an output signal of the coil indicative of linear velocity.

Abstract: A method and system for determining the velocity of a rotating device is described herein. The system includes an apparatus with a set of sense magnets affixed to a rotating shaft of the rotating device and a circuit assembly. The circuit assembly includes a circuit interconnection having a plurality of sense coils and sensors affixed thereto. The circuit assembly is adapted be in proximity to the set of sense magnets on the rotating part. A controller is coupled to the circuit assembly, where the controller executes an adaptive algorithm that determines the velocity of the rotating device. The algorithm is a method of combining a derived velocity with a velocity from the tachometer.

Abstract: A signal generator for an internal combustion engine for obtaining precise information on a rotational direction of the engine when the engine runs at extremely low speed, comprising: a rotor having a first series of reluctor corresponding to a cylinder of the engine, and a second series of reluctor having a predetermined phase relationship relative to the first series of reluctor; and a first sensor and a second sensor that detect the first series of reluctor and the second series of reluctor, respectively of the rotor to generate pulses, wherein a positional relationship between the first and the second series of reluctors, and a positional relationship between the first and the second sensors are set so that a difference occurs in a phase relationship between an output pulse of the first sensor and that of the second sensor in forward rotation and in reverse rotation of the engine.

Abstract: Linear velocity sensor and method for reducing non-linearity in the output signal of the sensor are provided. The sensor comprises a ferromagnetic housing including an opening. The sensor further comprises a spool disposed in the housing. The spool includes a bore for receiving a slidable ferromagnetic rod. The ferromagnetic rod may be extendable through the opening in the housing. A magnet is mounted at the one end of the rod distal from the opening when the rod is substantially inserted in the bore. A coil is wound on the spool. The number of turns of the coil is arranged to taperingly increase as the coil progresses from an end of the spool proximate the opening in the housing to the opposite end of the spool. The tapering arrangement for the number of turns of the coil is selected to reduce non-linearity of an output signal of the coil indicative of linear velocity.

Abstract: A circuit for inputting and processing a signal from a speed sensor element, includes a comparator having first and second input terminals and first and second input circuits connected to receive the signal. The first input circuit is connected to a first input terminal of said comparator, and the second input circuit is connected to a reference voltage and to the second input terminal of said comparator. A switchable voltage divider circuit interruptibly connecting a voltage divider circuit for reducing an amplitude of the signal on said first input circuit; and a microprocessor is connected to receive and process an output of the comparator and to determine a speed value based thereon. The microprocessor controls switchable voltage divider based on the magnitude of determined vehicle speed.

Abstract: A drive unit for calibrating an indicator/meter of a vehicle is provided in which a pointer in an indicator for a vehicle can point immediately after an ignition switch is turned ON, and the frequency of seeing motion of the pointer in an initializing operation by a car driver is reduced. A sensing mechanism (8a-3) is provided to sense an open/close operation of a door. Correspondingly to the sensing of the sensing mechanism (8a-3), a drive-start mechanism (8a-4) starts rotation of a stepping motor using a drive mechanism (8a-1) for initialization. The drive mechanism (8a-1) during initialization rotates the stepping motor to move a driven member toward a stopper.

Abstract: An apparatus and method for determining linear and angular velocity of a moving body. A magnet is attached or fixed to the body, the velocity of which is to be determined. The apparatus comprises a sensor comprising a core of magnetic material and a coil wound about the core. The movement of the body and magnet relative to the core effects a time-varying magnetic field between the magnet and the core thereby producing Barkhausen effect time-varying voltage signals in the coil. The apparatus further comprises a system for detecting and processing the time-varying voltage signals so as to effect a transformation of the signals into data defining the velocity of the moving body.

Abstract: The present invention relates to a method and a circuit arrangement for processing signals for an active motion sensor which generates at least one first sequence of input pulses that contain motion information. By at least one integrating filter circuit, each input pulse of a pulse train is integrated, and an associated output pulse is generated during a period in which the integrated signal is in excess of a predeterminable second threshold value after a predeterminable first threshold value has been exceeded so that the output pulse has a time delay with respect to the input pulse. As a result, noises of a duration which is shorter than the delay time are effectively suppressed.

Abstract: A sensing system for measuring the angular displacement of a rotating shaft is disclosed. The sensing system comprises a rotor and a sensor assembly disposed within the rotor. The rotor is constructed and arranged to be securably mounted to the shaft such that the rotor rotates in concert with the shaft. Furthermore, the rotor defines a plurality of teeth extending radially inwardly towards a center of the shaft. The sensor assembly comprises a sensor housing and a magnet arrangement disposed within the housing. The magnet arrangement defines a magnetic flux path between the sensor assembly and the rotor. As a result, the magnet arrangement and the rotor cooperate to define a magnetic circuit. Changes in magnetic flux through the magnetic circuit can be measured to determine the angular displacement of the rotating shaft.

Abstract: A method and apparatus for determining the velocity of a rotating device is described herein. The apparatus includes a magnet assembly affixed to a rotating shaft of a rotating device and a circuit assembly. The circuit assembly includes a circuit interconnection having a sense coil and sensors affixed thereto.

Abstract: Inductive sensor for non-contact detection of discontinuities of a conductive or ferromagnetic target for determination of target position, movement and speed, or generally of a magnetic image, including a plurality of receiving secondary windings associated with each exciting primary winding, configured to obtain electric signals optimized as a function of the discontinuities of the target. The sensor, combined with a suitable electric measuring circuit, allows global analysis of the signals provided by the secondary windings and configuration of a network in accordance with a predefined selection. An adaptive circuit allows auto-calibration of the sensor.

Abstract: The invention relates to a method for determining the position and/or the speed of motion of a control element which can be moved back and forth between a first and second switching position. According to said method, an immersion body which is connected to the control element is guided through at least one stationary plunger coil, synchronously with the motion of said control element. The voltage that is generated as a result of the immersion body moving in relation to a permanent magnet and/or a permanent magnet moving in relation to the plunger coil is detected as a signal for the speed of motion of the control clement. The changes in impedance and or a current that are caused as a result of the movement of the immersion body in the plunger coil are detected as a signal for the position of the control element.

Abstract: A wheel for roller skates or roller boards, the wheel having a non-rotating axle of rotation and a wheel body rotatable around an axle of rotation, the wheel includes means for measuring the speed at the wheel and means in the wheel for determining its rate of rotation and/or the actual rate of travel of a user of the roller skate or roller board or other sports equipment containing the wheel.

Abstract: A sensing coil affixed to the outside of an induction motor housing uses flux signals from the motor to measure motor speed. In particular, components of the rotor current are measured and compared to analysis from stator fundamentals and sidebands to determine the true rotor frequency which can then be used to determine the motor speed. A shield and/or a compensating coil can optionally be used to filter out extraneous signal noise.

Abstract: In a rotation sensor having a resolver attached to a rotor and a signal processing unit for angle detection for supplying a reference signal having a predetermined periodic waveform to the resolver, allowing the resolver to generate a sin signal having a waveform obtained by amplitude-modulating the reference signal by sin &thgr; and a cos signal having a waveform obtained by amplitude-modulating the reference signal by cos &thgr;, and detecting the angle &thgr; on the basis of the sin signal and cos signal, there are provided a signal processing unit for rotation detection for outputting a rotation pulse signal and a reference position signal on the basis of the angle &thgr; and a signal process abnormality detecting unit for detecting the presence or absence of an abnormality in the signal processing unit for angle detection on the basis of the angle &thgr; and an angle &thgr;′ calculated from both of the rotation pulse signal and the reference position signal of the signal processing unit for rotatio

Abstract: In the case of a method for checking the width of the measuring air gap of a magnetic speed sensor, square-wave output signals are generated from the measurement signals of the sensor by means of at least one prescribable threshold value. The pulse duty factor of the output signals is held within a prescribed range in the case of an acceptable gap width. In the case of amplitudes of the measurement signal outside prescribed limits, the pulse duty factor deviates in a reliably measurable fashion from the prescribed range. A circuit has the means for carrying out this method.

Abstract: A revolving speed detecting device for use with a rolling contact bearing having a rotary ring and a fixed ring. It has a magnetic ring provided on the peripheral surface thereof with a plurality of teeth at equal pitches and mounted on the rotary bearing ring. A sensor made of soft ferrite or by laminating a plurality of silicon steel plates is mounted on the fixed bearing ring opposite to the teeth of the magnetic ring. A coil is wound around the sensor. A high-frequency voltage generator is connected to the coil. A detecting device for detecting the output voltage of the coil is also connected to the coil.

Abstract: An apparatus and method for testing, for example, ABS systems in which a variable reluctance detector is positioned adjacent a ring of ferromagnetic teeth mounted on a wheel is provided. The amplitude and period of individual cycles of the output of the detector are measured and the product of the measured amplitude and period is calculated to provide an indication of the performance of the ABS detector system. The rate of change of the product may be analyzed to more reliably distinguish fault conditions from the effects resulting from, for example, variations in the speed of the wheel. The peak-to-peak amplitude of the product may be monitored to indicate tooth eccentricity, and the mean of the product may be monitored to indicate the detector-to-tooth gap.

Abstract: A method for monitoring a rotor speed of an X-ray tube anode drive includes acquiring axial flux pickup data from the rotor, using the axial flux pickup data to provide a flux spectrum, and estimating the rotor speed by analyzing the flux spectrum. The step of acquiring axial flux pickup data can include situating an axial leakage flux pickup coil so as to pick up a flux signal from an X-ray tube anode drive rotor while the rotor rotates. An analog flux signal can be converted to a digital flux signal and a fast Fourier transform can be used to transform the digital flux signal into a flux spectrum. The flux spectrum can be used to estimate a drive frequency and a slip frequency and the speed can be estimated by subtracting the slip frequency from the drive frequency and dividing by the number of pole pairs of the X-ray tube anode drive.