An apparatus for tensioning a fastener while measuring displacement of the fastener relative to a female threaded member may include a driver extension having an interior channel aligned along the extension's central cylindrical axis, open to a socket driver at an output end of the driver. The apparatus may further include a measurement probe in the interior channel, coupled to a measurement indicator on an exterior of the extension by a coupling that moves the measurement indicator in proportion to movement of the measurement probe and a measurement gauge coupled to an exterior of the driver extension that gauges displacement of the measurement indicator. A method for using the apparatus includes driving a female threaded member along a threaded rod by the driver extension while holding the measurement probe against an end of a bolt, screw, or other threaded fastener of which the threaded rod forms a part and while reading the measurement gauge.

Circuits for controlling magnetic-based tracking systems are described. These systems may be used in virtual reality applications, for example to track in real-time the location of one or more body parts. The systems use a beacon emitting mutually orthogonal magnetic fields. On the receiver side, one or more sensors disposed on different parts of a body receive the magnetic fields. The beacon includes switching amplifiers for driving the magnetic field emitters. Being binary, these amplifiers may be controlled by binary signals. The circuits may exhibit a resonant frequency response, and may be operated off-resonance, thus providing for a better control of the magnetic fields amplitude. As a result, however, fluctuations in the envelop of the magnetic fields due to the presence of a beating tone may arise. These fluctuations may be shortened by gradually activating the drivers for the magnetic field emitters.

The invention relates to a measuring device having a transmitter (1, 2, 3) for transmitting a measurement signal, a receiver (4) for receiving a response to the transmitted measurement signal, and a signal processing device (7, 8, 9; 18) for determining a measurement result from the response, the transmitter and/or the receiver having a coil (3; 4; 16), the measuring device having a calibration device for reducing an interference influence on the measurement result, characterized in that the calibration device is configured such that a current pulse can be introduced into the coil (3; 4; 16) from a current source (DC) and the signal processing device (7, 8, 9; 18) can perform a measurement value correction using the calibration signal generated by the current pulse and can determine a measurement result from the response and the measurement value correction.

The invention further relates to a measuring method.

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

An integrated circuit is provided for use in a sensor system having a plurality of sensing coils arranged in a star configuration coupled to terminals of an integrated circuit, such that a first and a second terminal are connected external to the integrated circuit via a loop including a first and a second sensing coil in the plurality of sensing coils. The integrated circuit includes: sensing circuitry for evaluation of sense signals received from the sensing coils via said terminals; a current source and a current sink coupled to respectively a first and a second of said terminals, such that upon supply of current from the current source a current is established through the loop external to the integrated circuit and a detection signal is generated; and an evaluator for evaluating one of more detection signals to detect failure and/or weakness within said loop.

A magnetic angular position sensor system is described herein, which includes a shaft rotatable around a rotation axis, the shaft having a soft magnetic shaft end portion. The system further includes a sensor chip spaced apart from the shaft end portion in an axial direction and defining a sensor plane, which is substantially perpendicular to the rotation axis. At least four magnetic field sensor elements are integrated in the sensor chip, with two of the magnetic field sensor elements being spaced apart from each other and are sensitive to magnetic field components in a first direction and wherein two of the magnetic field sensor elements are spaced apart from each other and are only sensitive to magnetic field components in a second direction, whereby the first and the second direction are mutually non-parallel and the first and the second direction being perpendicular to the rotation axis.

The present invention concerns a sensor device (1) comprising a transducer (3) adapted to generate a magnetic field (MF), the sensor device (1) is configured to measure a beating gap (G) between a first (5) and a second (7) refining disc of a refiner apparatus (9) and is configured to be mounted in the first refining disc (5), the sensor device (1) comprises a magnetic pole (13), a coil assembly (15) and a measuring head (11′), which measuring head (11′) is configured to be set in calibration position relative to the second refining disc (7) for calibration of the sensor device (1). The measuring head (11′) comprises an outer end (10′) made of a non-magnetic material configured to be positioned in abutment with the second refining disc (7) in a calibration sequence. The present invention also concerns a method of calibration of said sensor device (1).

This disclosure provides systems, methods and apparatus for detecting foreign objects. In one aspect an apparatus for detecting a presence of an object is provided. The apparatus includes a resonant circuit having a resonant frequency. The resonant circuit includes a sense circuit including an electrically conductive structure. The apparatus further includes a coupling circuit coupled to the sense circuit. The apparatus further includes a detection circuit coupled to the sense circuit via the coupling circuit. The detection circuit is configured to detect the presence of the object in response to detecting a difference between a measured characteristic that depends on a frequency at which the resonant circuit is resonating and a corresponding characteristic that depends on the resonant frequency of the resonant circuit. The coupling circuit is configured to reduce a variation of the resonant frequency by the detection circuit in the absence of the object.

Methods and apparatus for high speed location determinations are disclosed. An example apparatus includes at least two coils arranged along a zone of interest to generate a magnetic field, and a sensor to measure a change in the magnetic field associated with the at least two coils as an object of interest moves within or into the zone of interest. The example apparatus also includes a processor to determine a position of the object of interest based on the measured change.

A control apparatus includes: a data acquisition part that acquires correction data indicating a content regarding a correction process which corrects an error of an angle at which a rotation angle sensor that measures a rotation angle of a rotor included in an electric motor is attached; a determination part that determines, based on the correction data, whether or not the correction process has been performed; and a control method determination part that determines, in a case where it is determined that the correction process has not been performed, that an inverter which supplies an AC current to the electric motor is controlled under a pulse-width modulation control.