Abstract: In order to implement two different sensitivities simultaneously in one component, in particular in an acceleration sensor having a substrate, at least one spring device, and at least one seismic mass, it is proposed that the spring device be designed for an intrinsically nonlinear behavior corresponding to a progressive spring characteristic curve, in which a greater acceleration is associated at least locally with a greater rigidity (spring constant).

Abstract: A volumetric densiometer flask for determining the volumetric density of a solute includes: (a) a first bulbous portion in a lower end section of the flask; (b) a second bulbous portion in an upper end section of the flask, the second bulbous portion comprising an open mouth at its upper end; (c) a central neck comprising a central channel in open communication with the first bulbous portion at an upper end of the neck, and the second bulbous portion at an opposite, lower end of the neck; and (d) a removable stopper that is closely insertable into the mouth of the second bulbous portion, the mouth being correspondingly sized to a lower end of the stopper. Also included herein is a procedure for determining the volumetric density of a given sample using the volumetric densiometer flask.

Abstract: The semiconductor inertial sensor is formed by a rotor element and a stator element electrostatically coupled together. The rotor element is formed by a suspended mass and by a plurality of mobile electrodes extending from the suspended mass. The stator element is formed by a plurality of fixed electrodes facing respective mobile electrodes. The suspended mass is supported by elastic suspension elements. The suspended mass has a first, larger, thickness, and the elastic suspension elements have a second thickness, smaller than the first thickness.

Abstract: An acceleration sensor unit including a board on which an acceleration sensor is mounted, a support part for supporting the board, and a housing in which the support part and the acceleration sensor are contained, the board is installed in the housing by means of the support part so as to swing with respect to the housing.

Abstract: The accelerometer has a base (2), an outer planar ring-like support frame (17) fixedly bonded to the base (2), and an inner planar ring-like support frame (18) flexibly suspended within the outer frame (17) by mounts (19) connecting the inner frame (18) to the outer frame (17) so that the inner frame (18) is spaced from the base (2), co-planar with the outer support fram (17) so as to provide flexible suspension for the inner support frame (18) reducing compressive and/or tensile forces on mounting legs (4) flexibly mounting a proof mass (3) in the inner support frame (18).

Abstract: The invention relates to a micromachined gyrometer having a planar moving structure anchored on a fixed substrate by anchoring feet, the fixed substrate being mounted on a support substrate via fasteners, the moving structure comprising at least two moving assemblies that are symmetrical with respect to an axis of symmetry A1; the anchoring feet are located outside this axis A1. The fixed substrate has etched features for the purpose of partly isolating at least one region from the rest of the fixed substrate, this region having a portion of the fixed substrate that includes at least one anchoring foot, and the fixed substrate is mounted on the support substrate via fasteners applied outside the region.

Abstract: Provided are a gyro-sensor including a plurality of component units and a method of fabricating the gyro-sensor. The gyro-sensor includes: a substrate; a micro electro mechanical system structure including a surface including a predetermined area in which a cavity is formed and connected to an upper surface of the substrate to output a vibration signal proportional to an external rotation force; and a circuit unit positioned in the cavity, converting the vibration signal into a predetermined electric signal proportional to a circular angular velocity, and outputting the predetermined electric signal.

Abstract: Disclosed is a small-sized vibration type gyrosensor device of high sensitivity provided with a cantilevered oscillator. A cantilevered oscillator 11, provided with a lower electrode, a piezoelectric film and an upper electrode, formed on a single-crystal silicon substrate by a thin film forming process, includes, as an upper electrode, a driving electrode 6a, formed along the length of the oscillator 11 for applying the voltage for causing oscillations of the oscillator 11, and first and second detection electrodes 6b, 6c, formed on both sides of the driving electrode 6a parallel to the longitudinal direction of the oscillator, without contacting with the driving electrode 6a. With a width W0 of the driving electrode 6a, a width W1 of the first detection electrode 6b, a width W2 of the second detection electrode 6c and with W=W0+W1+W2, the condition of 0.5<(W0/W)<1 is to be met.

Abstract: Provided are an angular velocity sensor with improved reliability by preventing an electric short circuit resulting from etching debris left on the bottom electrode after the etching of the conductive layers, and a method for manufacturing the angular velocity sensor. The drive electrode unit, the monitor electrode unit and the sensing electrode unit are each provided with bottom electrode (29) formed on substrate (33) having the shape of a tuning fork, piezoelectric film (30) made of piezoelectric material and formed on bottom electrode (29), and top electrode (31) formed on piezoelectric film (30). Ends (31T) of top electrode (31) are located inside ends (30T) of piezoelectric film (30) so as to expose ends (30T) of piezoelectric film (30) beyond top electrode (31), thereby forming exposed parts (32). When exposed parts (32) have a thickness of “t”, piezoelectric film (30) is made to have an exposed width (L) of not less than 0.3 t.

Abstract: An Integrated gyroscope includes a suspended mass; mobile actuation electrodes extending from the suspended mass; and a sensing mass connected to the actuation mass through coupling springs. The suspended mass is formed by an external part and an internal part, electrically separated by an electrical-insulation region having a closed annular shape. The electrical-insulation region is laterally completely surrounded by the external part and by the internal part. In one embodiment, the suspended mass has the shape of a closed frame delimiting an opening, the sensing mass is formed inside the opening and is connected to the internal part, and the mobile actuation electrodes are connected to the external part.

Abstract: A piezoelectric vibrating gyro element is constructed by crystal and includes at least in the same plane a base portion; a pair of vibrating arms for detection extended out from the base portion to both sides in a straight line shape, and having groove portions; a weight portion connected to the tip of each of the vibrating arms for detection; a pair of connecting arms extended out from the base portion to both the sides in directions perpendicular to the vibrating arms for detection; pairs of vibrating arms for driving each extended out from the tip portion of each of the connecting arms to both the sides perpendicularly to this tip portion, and having groove portions; and a weight portion connected to the tip of each of the vibrating arms for driving; wherein, when the vibrating arm for driving is set to Ld in length and Wd in width, and the vibrating arm for detection is set to Lp in length and Wp in width, and the connecting arm is set to Lc in length and Wc in width, the piezoelectric vibrating gyro elem

Abstract: Correcting unbalance with regard to rotors (11, 101) and shafts is important in order to improve performance of those rotors (11, 101) or shafts within a practical machine or engine. Previously, result orientated iterative balancing of the rotor or shaft has been achieved in which mass has been added or possibly intrusive and distorted adjustments in drag and stiffness presented through bearings or alteration of the rotor (11, 101) itself have been utilised to improve rotor balance performance. In the present invention, a dynamic bearing 13 is utilised in order to provide force components with some components in phase with rotor deflection in order to simulate negative stiffness and/or some force components in phase with rotor velocity in order to simulate negative drag upon the rotor (11, 101). In such circumstances, a more accurate determination of rotor unbalance is achieved to enable known techniques of perturbed boundary condition analysis for balance correction to be implemented more accurately.

Abstract: The invention relates to an inertial sensor based on the magnetic levitation of an inertial mass comprising an active magnetic bearing unit arranged in such a way as to levitate the inertial mass and characterized by the fact that it furthermore comprises additional active magnetic bearings units arranged in such a way as to control the position of said inertial mass along three independent axis and to create, for any of said independent axis, restoring forces that can be oriented in any of the two directions of these independent axis.

Abstract: In a device (3) for fastening balancing weights to rotors (2) with a plurality of compensation planes, in particular to propeller shafts or Cardan shafts, preferably in a balancing machine (1) that includes at least one gripper-like device which can be positioned along the rotor axis, and with which a balancing weight is placed on the external periphery of the rotor (2) and can be fastened there, the gripper-like device (5) includes plural receivers for receiving a plurality of the balancing weights.

Abstract: A device for detecting a resonant frequency comprises a sound source, a switch, a mixer, and a sound meter. The switch and mixer are capable of switching between a first state in which the switch and mixer output a measurement signal and a second state in which the switch and mixer output a synthesized signal containing the measurement signal and the signal output from a microphone. The device detects the resonant frequency based on comparison between the first amplitude frequency characteristic measured in the first state and the second amplitude frequency characteristic measured in the second state.

Abstract: A semiconductor acceleration sensor in which a reduction in size can be achieved when electrodes are formed in a chip main body and acceleration can be measured with good sensitivity. The semiconductor acceleration sensor comprises a weight section, flexible sections which support the weight section and have measurement elements P, and a chip main body which has a front surface having chip electrodes electrically connected with the measurement elements, and support the flexible sections, wherein an additional weight, which has an inclined face which surrounds a bonding section and decreases its size toward the bonding section, is bonded on the front surface of the weight section.

Abstract: A multiparameter acoustic signature inspection device and method are described for non-invasive inspection of containers. Dual acoustic signatures discriminate between various fluids and materials for identification of the same.

Abstract: An acceleration sensor chip has a frame portion having a frame body portion and protruding portions. The acceleration sensor chip also includes a mobile structure having a central weight portion supported movably by four beam portions. The mobile structure also has four rectangular parallelepiped-form protruding weight portions The acceleration sensor chip also includes a plurality of stoppers extending above the protruding weight portions.

Abstract: The present invention provides an apparatus and method for measuring the angular rotation of a moving body. The apparatus comprises an upper sensor layer, a lower handle layer substantially parallel to the sensor layer, at least one dither frame formed of the upper sensor layer, the frame having a dither axis disposed substantially parallel to the upper sensor layer and the lower handle layer. The apparatus further comprises a first accelerometer formed of the upper sensor layer and having a first force sensing axis perpendicular to the dither axis for producing a first output signal indicative of the acceleration of the moving body along the first force sensing axis, the first accelerometer having a proof mass and at least one flexure connecting the proof mass to the dither frame such that the proof mass can be electrically rotated perpendicular to the dither axis.

Abstract: Accelerometers for determining acceleration and methods of fabricating an accelerometer are disclosed. In one embodiment, the accelerometer includes a frame, a mass movably suspended on the frame, a fixed element having a rounded surface that does not move with respect to the frame, a movable element having a rounded surface that moves with the mass, and a sensing coil of optical waveguide wrapped around the rounded surfaces to detect movement of the mass in response to acceleration based on interferometric sensing of a change in length of the sensing coil. A method of fabricating the accelerometer includes suspending the mass in the frame and wrapping the optical waveguide around the rounded surfaces. Sensitivity and low fabrication cost of the accelerometers enables their use for integration within an ocean bottom seismic cable. Further, the accelerometer may be an in-line or a cross-line accelerometer depending on the arrangement within the frame.