Abstract: An angular velocity sensor including a drive extension mode. In one aspect, an angular rate sensor includes a base and at least three masses disposed substantially in a plane parallel to the base, the masses having a center of mass. At least one actuator drives the masses in an extension mode, such that in the extension mode the masses move in the plane simultaneously away or simultaneously towards the center of mass. At least one transducer senses at least one Coriolis force resulting from motion of the masses and angular velocity about at least one input axis of the sensor. Additional embodiments can include a linkage that constrains the masses to move in the extension mode.

Abstract: A shaft imbalance detector system (50) includes a speed sensor (52) that detects a speed of a wheel and generates a speed signal, and a controller (60) connected to the speed sensor (52). The controller (60) is configured to monitor the speed signal, where a variation in the speed signal indicates an imbalance in a shaft (22).

Abstract: A device for exciting a landing gear of an aircraft while it is on the ground. The device includes an oblong bracing foot, a movable support on which the oblong foot is mounted and an arrangement for setting the gear into vibration.

Abstract: A deterioration checking device (2) includes a sight glass (3) through which deterioration of a biofuel stored in a fuel tank is observable as a change in the color of the biofuel, and first and second benchmark sections (4a, 4b) each of which three color samples (11a, 11b, 11c) corresponding to different degrees of deterioration of the biofuel are arranged along the sight glass (3). Deterioration is determined by observing the color samples (11a, 11b, 11c) through the biofuel in the sight glass (3). The arrangement of the color samples (11a, 11b, 11c) of the first benchmark section (4a) and that of the color samples (11a, 11b and 11c) of the second benchmark section (4b) are reversed to each other, so as to cope with the lowering of the liquid level of the biofuel and the rising of the liquid level of a water layer.

Abstract: A quadrupole responder for an OQR-type gravity gradiometer comprises a housing, and a mass quadrupole positioned within the housing. The mass quadrupole has a pair of sides, and also has a center of mass between the sides. At least a pair of torsion spring flexures are provided by pins connecting said side of said mass quadrupole to the housing. The torsion spring flexures provide an axis of rotation which passes through the center of mass of the mass quadrupole and through both spring flexures. The pins are integral with the mass quadrupole.

Abstract: Fluid tanks in a hospital or similar environment include sensors to detect, e.g., state and location, which can be communicated to a central station where this data can be processed to permit predictions of resource usage and enable automated management of the fluid tanks.

Abstract: Disclosed herein is an angular velocity sensor including: first and second mass bodies; a first frame provided at an outer side of the first and second mass bodies; a first flexible part connecting the first and second mass bodies to the first frame in a Y axis direction, respectively; a second flexible part connecting the first and second mass bodies to the first frame in an X axis direction, respectively; a second frame provided at an outer side of the first frame; a third flexible part connecting the first and second frames to each other in the X axis direction; and a fourth flexible part connecting the first and second frames to each other in the Y axis direction, wherein the first frame has a thickness in a Z axis direction thinner than that of the second frame.

Abstract: A photoacoustic imaging apparatus performs imaging of an optical absorber. The photoacoustic imaging apparatus includes a light source, a detector configured to detect an acoustic wave generated from the optical absorber that has absorbed energy of light emitted from the light source, and a signal processing unit configured to form an image of the optical absorber. The signal processing unit stores information indicating whether a rate of change in pressure of the acoustic wave detected by the detector is positive or negative before performing a waveform process on the acoustic wave.

Abstract: Wheel balancers and methods of their use are disclosed. One wheel balancer includes a cable and a base. The cable has a support end for being fastened to a support. The base is configured for receipt inside a wheel, and the base has proximal and distal ends and a hollow interior area for passing the cable therethrough. The cable passes through the base interior area and is operatively coupled to the base such that a distance between the cable support end and the base distal end is generally constant when the cable is extended. A pivot point for the cable is movable relative to the base between the base distal end and the cable support end.

Abstract: A MEMS device includes a substrate, a mass having a first and second set of elongated mass fingers extending from the mass, and a support structure supporting the mass on the substrate. The support structure may include at least one anchor and a plurality of springs that allow movement of the mass relative to the substrate. The MEMS device may also include a first set of sensing fingers for sensing movement of the first set of mass fingers relative to the first set of sensing fingers, and a second set of sensing figures for sensing movement of the second set of mass fingers relative to the second set of sensing fingers. The first and second sets of sensing fingers may have different size finger gaps between the sensing fingers and the respective mass fingers.

Abstract: A method comprises positioning an ultrasonic probe against a surface of an item. The probe includes a chamber formed in part by a flexible membrane, which is opposite the surface. The method further comprises moving the probe along the surface while varying chamber pressure to flex the membrane to accommodate the surface.

Abstract: An acceleration device includes an actuator configured to displace a mass in a reciprocating motion at a desired frequency, a mount configured to hold a device, such as an accelerometer device, and at least one spring connecting the mount to the mass. The actuator is used to apply a force to achieve resonance. The actuator may comprise a voice coil motor, wherein the voice coil motor includes a permanent magnet and an armature and wherein said armature comprises part of said mass. The actuator applies a periodic force to the mass. The periodic force may be a sinusoidal force. Preferably, the applied force is aligned with a resulting velocity of the mass. The mount may include a test socket to which the device is electrically connected. The spring may comprises one or more flexure elements. The acceleration device may be used with a handler device to connect and disconnect the device to and from the mount. Optionally, the handler device includes an environmental chamber surrounding the mount.

Abstract: A MEMS device comprises a proof mass suspended above a substrate, one or more driving combs, and one or more sensing combs. During operation, a DC actuating potential in series with an AC modulation potential is applied to the proof mass, and an AC actuating potential is applied to the one or more driving combs such that the proof mass moves in an oscillatory manner. An inertial sensing system further comprises a sensing element configured to detect a rotation information coupled with an AC signal and an acceleration information coupled with a DC signal.

Abstract: A tri-axis accelerometer includes a proof mass, at least four anchor points arranged in at least two opposite pairs, a first pair of anchor points being arranged opposite one another along a first axis, a second pair of anchor points being arranged opposite one another along a second axis, the first axis and the second axis being perpendicular to one another, and at least four spring units to connect the proof mass to the at least four anchor points, the spring units each including a pair of identical springs, each spring including a sensing unit.

Abstract: This disclosure provides systems, apparatus, and devices and methods of fabrication for electromechanical devices. In one implementation, an apparatus includes a metal proof mass and a piezoelectric component as part of a MEMS device. Such apparatus can be particularly useful for MEMS gyroscope devices. For instance, the metal proof mass, which may have a density several times larger than that of silicon, is capable of reducing the quadrature and bias error in a MEMS gyroscope device, and capable of increasing the sensitivity of the MEMS gyroscope device.

Abstract: Method of angular measurement by means of a sensor comprising an axisymmetric resonator associated with means for setting the resonator into vibration and with means for detecting an orientation of the vibration with respect to a reference frame of the sensor, comprising the steps of applying a precession control so as to slave an orientation of the vibration to an angular setpoint value and of determining an angular measurement on the basis of the precession control. The method comprises a phase of modulating the angular setpoint value in such a way that the said setpoint value uniformly sweeps an angular span of ? radians and that a temporal derivative of the setpoint is deducted from the precession control prior to the determination of the angular measurement.

Abstract: A passive dynamic inertial rotor balance system including a plurality of balancing members fitted onto a rotor shaft at locations of predicted maximum shaft modal deflection. Each of the balancing members has at least one chamber and located within the at least one chamber is a plurality of movable weights and a viscous fluid. As the shaft accelerates toward an unbalance point, the weights move within the at least one chamber to a location which is opposite from the unbalance point. The viscous fluid provides damping for the movable weights to prevent excess movement within the chamber and to provide lubrication thereof. A system for self-correcting an unbalance of a turbomachinery rotor during rotation of the rotor and a method for balancing a rotor in a turbomachinery is also provided.

Abstract: Frequency-steerable acoustic transducers (FSATs) that allow directional generation or sensing of waves propagating in two-dimensional domains. Directionality is the result of the spatial filtering effect produced by the characteristic shape of the sensing surface. A wavenumber spiral FSAT (WS-FSAT) maps the direction of wave sensing in the [0°, 180°] range to a specific frequency component in the spectrum of the received signal. The use of a wavenumber spiral FSAT operating in sensing mode can be used for the localization of broadband acoustic events. One configuration includes a broadband source generating guided elastic waves in an isotropic plate. The WS-FSAT records the plate response and defines the source location through a time-frequency analysis of the received signal. The frequency selective response of the WS-FSAT directly maps the dominant component of the received signal to the direction of arrival of the incoming wave, thus greatly facilitating the source localization procedure.

Abstract: An accelerometer device having a proof mass, a support base, a hinge that flexibly connects the proof mass to the support base, a double-ended fork (DETF) having two tines. The tines are made of only piezoelectric material. A plurality of electrode surfaces surround at least portions of the tines for inducing electric fields at the first tine is opposite a direction of the induced electric field at the second tine at similar locations along a longitudinal axis of the tines. This causes the tines to resonate in-plane and out of phase.

Abstract: A microelectromechanical gyroscope having a microstructure that includes a first mass and a second mass, wherein the first mass is oscillatable according to a first axis and the second mass is constrained to the first mass so as to be drawn along by the first mass according to the first axis and to oscillate according to a second axis, in response to a rotation of the microstructure, a driving device coupled to the microstructure to maintain the first mass in oscillation at the driving frequency, and a reading device that detects displacements of the second mass according to the second axis. The gyroscope is provided with a self-test actuation system coupled to the second mass for applying an electrostatic force at the driving frequency so as to move the second mass according to the second axis.