Abstract: A rotary accelerometer having a nonrotatable cylindrical magnet return path formed out of magnetic permeable material. One or more permanent magnets, with two opposite poles, are disposed around the magnetic return path. An electrically conductive cup with an access for rotation therearound in which the cup surrounds the permanent magnets and the permanent magnets are arranged so as to produce a magnetic field through the cup into the nonrotatable cylindrical magnet return path, thereby inducing eddy currents inside the cup when rotating in the magnetic field. A stator core is formed out of magnetic permeable material surrounding the cup and nonrotatable relative thereto, the stator core having at least two pickup members. The stator is formed from at least one continuous piece of magnetic permeable material. One or more stator windings are disposed on to the pickup members of the stator core for sensing changes in a secondary magnetic field generated by the eddy currents in the cup.

Abstract: A speed sensor for sensing a rotating speed of a wheel is provided. The speed sensor includes a thermoplastic sensor body. A mounting ring is connected to the sensor body. The mounting ring can include a flange portion. A plastic insert is integrally molded into the sensor body adjacent the mounting ring. An active sensor element is located in a lower end of the plastic insert, a face of the active sensor element being vertically spaced a predetermined distance from the flange portion. A pair of terminals is electrically connected to the active sensor element. The pair of terminals extends from an upper end of the plastic insert. The flange portion, when pressed onto a hub associated with the wheel, is adapted to space the active sensor element an operating distance from a tone wheel mounted to the hub.

Abstract: A ground anchorage testing arrangement having an impulse imparting apparatus connectable to a ground anchorage tendon (20) or element thereof to be tested, the impulse imparting apparatus comprising an attachment means (22) for attachment to the ground anchorage tendon (20), a movable mass (31), a guide (28, 34) for guiding movement of the mass in the direction substantially aligned with the axis 0 of the ground anchorage to be tested and a drive means for imparting a driving force to move the mass in said direction (not shown). A method of assessing the integrity of ground anchorages, the method comprising the steps of (a) imparting a load impulse to a ground anchorage tendon to be tested, (b) monitoring the vibrational response signal of the anchorage to the imparted load impulse, (c) conditioning the vibrational response signal and (d) applying the conditioned vibrational response signal to an artificial neural network.

Abstract: An angular velocity sensor includes first exciters providing a vibrator with drive vibration, a piezoelectric element having a vibration detector for detecting vibration level of the vibrator, and Coriolis detectors for detecting Coriolis vibration depending on an input angular velocity, and including a driving circuit for receiving a signal from the vibration detector and issuing a signal to the first exciters and a detection circuit for receiving signals from the Coriolis detectors. The circuit section further includes a level judging circuit for judging abnormal levels of electric charges in the Coriolis detectors and a fail detector for issuing an output when abnormality is detected. Each output of the Coriolis detectors contains a drive vibration component larger than the reference level of the level judging circuit, and the layout of the electrodes in the element section is adjusted so that combined output may contain the component smaller than the reference level.

Abstract: An angular velocity sensor according to an embodiment of the present invention includes: a supporting substrate; a support-fixing portion disposed in the supporting substrate; a first supporting beam connected to the support-fixing portion; a first oscillator supported with the first supporting beam; a second supporting beam connected to the first oscillator; a second oscillator supported with the second supporting beam oscillating in the direction that a Coriolis force is generated; driving electrodes for driving the first oscillator and the second oscillator in a predetermined direction; and detecting electrodes for detecting the displacement of the second oscillator caused by the Coriolis force applied to the second oscillator, wherein the first supporting beam extends at least in the direction orthogonal to the oscillating direction of the first oscillator, both ends of the first supporting beam being connected to the first oscillator, and a longitudinally intermediate portion of the first supporting beam

Abstract: In order to detect buried compliant objects such as land mines and pipes, an acoustic signal is directed into the ground to excite vibration of a buried compliant object. A probing signal is also directed into the ground toward the vibrating object, and the probing signal is modulated and reflected by the vibrating object. The modulated, reflected probing signal is processed to determine therefrom the presence of the buried compliant object.

Abstract: An angular velocity sensor has a weight portion that can be drive-oscillated in a driving direction and be oscillated in a detecting direction when an angular velocity is applied, and unnecessary oscillation suppressing electrodes that can generate an electrostatic force to be applied to the weight portion in the detecting direction. The electrostatic force prevents the weight portion from being drive-oscillated in a direction other than the driving direction. As a result, unnecessary oscillation of the weight portion can be prevented even when the angular velocity sensor has a processing error.

Abstract: One aspect of the present invention is therefore a method for balancing a hollow cylindrical, rotatable object that is coupled to a drive source that is configured to rotate the rotatable object without a central shaft. The method includes steps of: mounting an arbor having a forward shaft and an aft shaft to an inner wall of the rotatable object so that the forward shaft and aft shaft are concentric to an axis of rotation of the rotatable object; operating the drive source to rotate the rotatable object and the arbor; measuring displacement of the forward shaft and the aft shaft of the arbor while the drive source is rotating the rotatable object; applying balancing weights to the rotatable object in accordance with the measured displacements; and removing the arbor from the rotatable object when a balance is achieved.

Abstract: An inertial measurement unit mountable on a vehicle, comprising a housing accommodating three solid state sensor couples, each couple comprising a gyro member and an associated accelerometer. The housing is in the shape of a triangular pyramid, with a base fitted with true position and fixation arrangements for positioning and fixing the housing at a predetermined relation with respect to an axis of the vehicle. Each of the solid state sensor couples is fitted on a respective face of the housing.

Abstract: A computer system and method for detecting periodic and quasi-periodic signals buried in wide-band noise is disclosed. For a signal containing periodic signals, the method includes the steps of segmenting the signal into an ensemble of block signals and performing a first Discrete Fourier Transform (DFT) on each block signal to obtain an ensemble of frequency signals containing complex data and frequency components. Next, the method includes the steps of defining an ensemble of complex frequency-time signals using the complex data from each frequency signal, performing a second DFT on each complex frequency-time signal to obtain an equivalent wave number signal for each frequency component, and identifying a peak magnitude component for each equivalent wave number signal.

Abstract: A microgyroscope has a baseplate made of the same material as the rest of the microgyroscope. The baseplate is a silicon baseplate having a heavily p-doped epilayer covered by a thick dielectric film and metal electrodes. The metal electrodes are isolated from the ground plane by the dielectric. This provides very low parasitic capacitive coupling between the electrodes. The thick dielectric reduces the capacitance between the electrodes and the ground plane.

Abstract: A self-retaining transmission sensor includes a sensor housing having a retaining ring extending radially from the sensor housing. When the self-retaining transmission sensor is inserted in a bore in a transmission housing having a diameter slightly smaller than the diameter of the retaining ring, the outer edge of the retaining ring engages the inner wall of the bore and holds the self-retaining transmission sensor firmly in place. Thus, the need for a mounting bracket, a mounting bolt, or a similar device is eliminated.

Abstract: A two axis gyroscope has a substantially planar vibratory resonator having a substantially ring or hoop-like shape structure, carrier mode drive means for causing the resonator to vibrate in a Cosn&thgr; out-of-plane carrier mode, where n has an integer value of 2 or more, support means for flexibly supporting the resonator, carrier mode pick-off means for sensing out-of-plane movement of the resonator, X axis response mode pick-off means for sensing in-plane Cosn1&thgr; response mode movement of the resonator in response to rotation of the gyroscope about the X axis, where n1 has a value of n+1 or n−1, and Y axis response mode pick-off means for sensing in-plane Sinn1&thgr; response mode movement of the resonator in response to rotation of the gyroscope about the Y axis where n1 has a value of n+1 or n−1, identical to that for the X axis response mode.

Abstract: An ultrasonic imaging system including an aberration correction system uses a harmonic component of the fundamental transmitted frequency for imaging, or for aberration correction, or both. By properly selecting the frequency pass bands of filters used in the image signal path and in the aberration correction signal path operating advantages are provided. The aberration correction values may be calculated concurrently with image formation.

Abstract: A driving signal is provided to six electrodes (driving electrodes) on one of the surfaces of each of three vibration legs of a three-pronged tuning-fork-type piezoelectric oscillator. Two output electrodes from among six electrodes (output electrodes) on the other surface thereof are connected to two current-to-voltage conversion devices, respectively. Since the two output electrodes are imaginarily short-circuited by the current-to-voltage conversion devices, there is no need to provide a ground electrode between the output electrodes. This makes it possible to simplify an electrode manufacturing process.

Abstract: A method and apparatus is disclosed for monitoring an angular displacement, such as angle position and the direction of displacement. The method and apparatus includes at least one resonator placed in proximity to a electrodynamic profile and exciting within said resonator an alternating electromagnetic field. The electromagnetic field should be at a frequency at which the electromagnetic field contacts the electrodynamic profile and then variations of the electromagnetic field parameters are measured for the resonator caused by rotating the electrodynamic profile. Excitation of the resonator is by an electromagnetic field in the form of at least one slowed electromagnetic wave having a suitable energy distribution of the electric and magnetic fields for measuring the electromagnetic field parameters.

Abstract: The invention relates to a method and device for simultaneously measuring multiple properties of a sample composed of multiple layers of films. The measurement features several steps. First, at least one source of excitation radiation irradiates the sample's surface to excite an acoustic mode. A probe source of radiation irradiates the acoustic mode and is diffracted off the surface of the sample to form a signal beam. A detector detects the acoustic mode to generate a signal beam, which is then analyzed to determine an acoustic frequency and an amplitude, a depth of modulation, or a decay constant. These properties are then further analyzed to determine of at least two properties (e.g., a thickness of two layers) of the sample.

Abstract: The present invention concerns a method and device for detecting an imbalance condition in a rotating washing machine tub. An indication of a power level required to maintain a given washing machine rotation speed is compared to a predefined standard power level associated with the given rotation speed, and a tub imbalance condition is detected in response to the comparison. The predefined standard power level may be stored in a memory device accessible by a processor that is programmed to calculate the power level required to achieve the given washing machine rotation speed and compare the required power level to the predefined standard power level to detect the tub imbalance condition.

Abstract: An angular accelerometer having a substrate, a fixed electrode supported on the substrate and including a first plurality of fixed capacitive plates, and a ring-shaped rotational inertia mass substantially suspended over a cavity and including a plurality of movable capacitive plates arranged to provide a capacitive coupling with the first plurality of fixed capacitive plates. A central member is fixedly attached to the substrate. A plurality of support arms extend between the central member and the ring-shaped mass for supporting the mass relative to the fixed electrode during rotational movement of the mass. The angular accelerometer also includes an input electrically coupled to the fixed electrode for receiving an input signal, and an output coupled to the mass for providing an output signal which varies as a function of the capacitive coupling and is indicative of angular acceleration.

Abstract: A microsensor with a resonator structure, which is excited by first electrical signals to oscillate and emits second electrical signals in dependence on the measuring variable, wherein a heating element, supplied with at least one of the first electrical signals, is arranged on the resonator structure for the thermal excitations of oscillations. For the thermal excitation of lateral oscillations in a microsensor with a resonator structure, the microsensor is provided at one oscillating part of the resonator structure with at least two regions that are thermally separated by a zone with reduced heat conductance, and the heating element is arranged on one of the regions. This type of arrangements permits the excitation of the resonator structure to lateral oscillations if the heating element is supplied with corresponding current pulses. It is advantageous if a receiving element is arranged on at least one of the other regions to detect the oscillation amplitude.