497 results about "Coriolis force" patented technology

Angular rate sensor for detecting rotation about first, second and third mutually perpendicular input axes having a plurality of generally planar proof masses coupled together for linear drive-mode oscillation along multi-directional drive axes in a plane formed by the first and second input axes. The masses are mounted on a generally planar sense frame for linear movements relative to the sense frame in drive-mode and for rotation together with the sense frame in sense modes. The sense frame is mounted for rotation with the masses in sense modes about the first, second, and third input axes independent of each other, in response to Coriolis forces produced by rotation of the masses about the first, second, and third input axes respectively. And capacitance sensors responsive to the rotational movements of the masses and the sense frame in sense modes are employed for monitoring rate of rotation.

An angular rate sensor made from a structural wafer of single crystal silicon has a pair of proof masses lying in an X-Y plane and supported by a circular frame. The masses are driven into oscillation in the X-direction using an interdigitated comb drive. Rotation of the sensor about the Z-axis induces Coriolis forces which cause the frame to rotate, the rotation of the frame being indicative of the angular rate of the sensor. A parallel plate sensor located outside of the circular frame senses rotation of the frame.

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.

Multi-axis micromachined accelerometer and rate sensor having first and second generally planar masses disposed side-by-side and connected together along adjacent edge portions thereof for torsional movement about axes parallel to a first axis in response to acceleration along a second axis and for rotational motion about axes parallel to the second axis in response to acceleration along the first axis. The masses are driven to oscillate about the axes parallel to the second axis so that Coriolis forces produced by rotation about a third axis result in torsional movement of the masses about the axes parallel to the first axis. Sensors monitor the movement of the mass about the axes, and signals from the sensors are processed to provide output signals corresponding to acceleration along the first and second axes and rotation about the third axis.

A sensor that measures angular velocity about an axis that is normal to a sensing plane of the sensor. The sensor comprises a sensing subassembly that includes a planar frame parallel to the sensing plane, a first proof mass disposed in the sensing plane, a second proof mass disposed in the sensing plane laterally to the first proof mass, and a linkage within the frame and connected to the frame. The linkage is connected to the first proof mass and to the second proof mass. The sensor further includes actuator for driving the first proof mass and the second proof mass into oscillation along a drive axis in the sensing plane. The sensor further includes a first transducer to sense motion of the frame in response to a Coriolis force acting on the oscillating first proof mass and the oscillating second proof mass.

A gyroscope comprises a piezoelectric substrate having a surface. Disposed on the surface are a resonator transducer, a pair of reflectors, a structure such as a metallic dot, and a sensor transducer. The resonator transducer creates a first surface acoustic wave on the surface. The pair of reflectors reflects the first surface acoustic wave to form a standing wave within a region of the surface between the pair of reflectors. The structure is disposed on the surface within the region, wherein a Coriolis force acting upon the structure creates a second surface acoustic wave. The sensor senses the second surface acoustic wave and provides an output indicative thereof.

A yaw-rate sensor having a substrate and a plurality of movable substructures that are mounted over a surface of the substrate, the movable substructures being coupled to a shared, in particular, central spring element, means being provided for exciting the movable substructures into a coupled oscillation in a plane that extends parallel to the surface of the substrate, the movable substructures having Coriolis elements, means being provided for detecting deflections of the Coriolis elements induced by a Coriolis force, a first Coriolis element being provided for detecting a yaw rate about a first axis, a second Coriolis element being provided for detecting a yaw rate about a second axis, the second axis being oriented perpendicularly to the first axis.

X type MEMS gyroscope has a first mass vertically vibrating on a substrate and a second mass horizontally vibrating on the substrate. A driving electrode is disposed on the same surface with the first mass. The first mass can move in relation to the second mass in the vertical direction, and is fixed in relation to the second mass in the horizontal direction. The second mass is operative to be moved in a horizontal direction in relation to the substrate by a Coriolis force, which is generated by an angular velocity applied while the first mass is being vibrated. A sensing electrode measures displacement of the second mass in the horizontal direction. All moving electrodes and stationary electrodes are disposed on the same surface, and all elements are manufactured by using one mask. Therefore, adhesion between the moving and stationary electrodes is prevented and the manufacturing process is simplified.

A sensor that measures angular velocity about an axis that is normal to a sensing plane of the sensor. The sensor comprises a sensing subassembly that includes a planar frame parallel to the sensing plane, a first proof mass disposed in the sensing plane, a second proof mass disposed in the sensing plane laterally to the first proof mass, and a linkage within the frame and connected to the frame. The linkage is connected to the first proof mass and to the second proof mass. The sensor further includes actuator for driving the first proof mass and the second proof mass into oscillation along a drive axis in the sensing plane. The sensor further includes a first transducer to sense motion of the frame in response to a Coriolis force acting on the oscillating first proof mass and the oscillating second proof mass.

Various embodiments of the invention allow for increased shock robustness in gyroscopes. In certain embodiments, immunity against undesired forces that corrupt signal output is provided by a chessboard-pattern architecture of proof masses that provides a second layer of differential signals not present in existing designs. Masses are aligned parallel to each other in a two-by-two configuration with two orthogonal symmetry axes. The masses are driven to oscillate in such a way that each mass moves anti-parallel to an adjacent proof mass. In some embodiments of the invention, a mechanical joint system interconnects proof masses to suppress displacements due to mechanical disturbances, while permitting displacements due to Coriolis forces to prevented erroneous sensor signals.

A micro angular rate-sensing device is provided. A vibrator, having a plurality of proof masses connected to a ring, is arranged in a first base. Flexible supporting members connect to the vibrator to suspend the vibrator in the first base. Electrodes drive the vibrator to oscillate and control the oscillation mode of the vibrator in driving mode. Planar electrodes are arranged relative to the proof masses on a second base. The motion of the proof masses relative to the planar electrodes is sensed through the capacitance between the proof masses and the planar electrodes. The resonant structure with greater mass of the device generates greater Coriolis force and increases the sensing area. Thus, the intensity of sensed signals and noise-signal ratio are greatly increased. Furthermore, the device does not rely much on high aspect ratio manufacturing technology. Thus the manufacturing cost is reduced and the yield rate is increased.

The present invention relates to a z-axial solid-state gyroscope. Its main configuration is manufactured with a conductive material and includes two sets of a proof mass and two driver bodies suspended between two plates by an elastic beam assembly. Both surfaces of the driver bodies and the proof masses respectively include a number of grooves respectively perpendicular to a first axis and a second axis. The surfaces of the driver bodies and the proof masses and the corresponding stripe electrodes of the plates thereof are respectively formed a driving capacitors and a sensing capacitors. The driving capacitor drives the proof masses to vibrate in the opposite direction along the first axis. If a z-axial angular velocity input, a Coriolis force makes the two masses vibrate in the opposite direction along the second axis. If a first axial acceleration input, a specific force makes the two masses move in the same direction along the first axis. If a second axial acceleration input, a specific force makes the two masses move in the same direction along the second axis. Both inertial forces make the sensing capacitances change. One z-axial solid-state gyroscopes and two in-plane axial gyroscopes can be designed on a single chip to form a complete three-axis inertial measurement unit.

Four sensor units (SUA1 to SUA4) are disposed symmetrically about a point, on both top and bottom and left and right centering around one point of a support (15e). Furthermore, four sensor units (SUA1 to SUA4) are designed so that all the components are fully in tuning-fork structure. Drive frames (5, 5) of the sensor units (SUA1, SUA2) disposed adjacent to each other in a first direction (Y) are vibrated in mutually inverted phases, and drive frames of the other sensor units (SUA3, SUA4) disposed adjacent to each other in a second direction (X) are vibrated in mutually inverted phases as well. Moreover, the drive frames of the sensor units (SUA1, SUA2) and the drive frames of the other sensor units (SUA3, SUA4) are operated in synchronization in the state in which phases are shifted by 90 degrees. Whereby, it is possible to reduce or prevent vibration coupling in the driving direction and in the detection direction, and the leakage (loss) of excitation energy and Coriolis force. Thereby, performance of an inertial sensor is improved.

X type MEMS gyroscope has a first mass vertically vibrating on a substrate and a second mass horizontally vibrating on the substrate. A driving electrode is disposed on the same surface with the first mass. When the first mass vertically vibrates, the second mass vibrates vertically together with the first mass. When angular velocity that is at a right angle to a movement direction of the first mass and the second mass is applied while the first mass is vertically vibrating, the second mass moves as Coriolis force is added to the second mass in a horizontal direction, and a sensing electrode measures displacement of the second mass in the horizontal direction. All moving electrodes and stationary electrodes are disposed on the same surface, and all elements are manufactured by using one mask. Therefore, adhesion between the moving and stationary electrodes is prevented and the manufacturing process is simplified.

An angular rate sensor having two generally planar proof masses, a drive axis in the plane of the masses, and an input axis perpendicular to the drive axis. The masses are suspended from a sensing frame and constrained for anti-phase movement along the drive axis in drive-mode. The sensing frame is mounted for torsional movement in sense-mode about the input axis in response to Coriolis forces produced by rotation of the masses about the input axis, with sensors responsive to the torsional movement of the sensing frame and the masses about the input axis for monitoring rate of rotation.

Four sensor units (SUA1 to SUA4) are disposed symmetrically about a point, on both top and bottom and left and right centering around one point of a support (15e). Furthermore, four sensor units (SUA1 to SUA4) are designed so that all the components are fully in tuning-fork structure. Drive frames (5, 5) of the sensor units (SUA1, SUA2) disposed adjacent to each other in a first direction (Y) are vibrated in mutually inverted phases, and drive frames of the other sensor units (SUA3, SUA4) disposed adjacent to each other in a second direction (X) are vibrated in mutually inverted phases as well. Moreover, the drive frames of the sensor units (SUA1, SUA2) and the drive frames of the other sensor units (SUA3, SUA4) are operated in synchronization in the state in which phases are shifted by 90 degrees. Whereby, it is possible to reduce or prevent vibration coupling in the driving direction and in the detection direction, and the leakage (loss) of excitation energy and Coriolis force. Thereby, performance of an inertial sensor is improved.

Transducers comprising a frame structure made of piezoelectric material convert energy, through piezoelectric effect, between electrostatic energy associated with voltage differential between the electrodes sandwiching the frame structure and mechanical energy associated with deformation of the frame structure. Inertial sensors such as gyroscopes and accelerators, including inertial sensors comprising ring resonators, utilize said transducers both to generate oscillations of their resonators and to sense the changes in such oscillations produced, in the sensors' frame of reference, by Coriolis forces appearing due to the movement of the sensors.

A mass flowmeter and a method for operating a mass flowmeter is based on the Coriolis principle and incorporates a Coriolis measuring tube, an oscillator associated with and stimulating said Coriolis measuring tube, and a transducer associated with the Coriolis measuring tube and which collects Coriolis forces and / or oscillations based on Coriolis forces. The electric power consumed in the mass flowmeter is controlled as a function of the available electric power. This permits the efficient use of the available electric power, thus permitting the operation of the mass flowmeter via a two wire interface that serves for both the input of electric power and the output of measuring data.

The invention discloses a double-closed-loop control circuit of a micromechanical gyroscope and belongs to the field of guide or control devices based on a Coriolis effect. The circuit is used for closed-loop control of driving and detection modes of the micromechanical gyroscope. A simplified self-oscillation closed-loop control circuit based on automatic gain control (AGC) is employed for the driving mode of the circuit, and the frequency stability and amplitude stability of the micromechanical gyroscope in the driving mode can be effectively improved; and a six-order continuous band-pass Sigma Delta M closed-loop control circuit for the detection mode has six-order noise reshaping capacity, and the signal to noise ratio (SNR), linearity and zero-bias stability of a system detection signal can be improved. The double-closed-loop control circuit of the micromechanical gyroscope is easy to control and simple, the accuracy of a system is improved, the SNR of the system is high, and the system is self-adaptively adjusted and high in stability.

Angular rate sensor for detecting rotation about first, second and third mutually perpendicular input axes having a plurality of generally planar proof masses coupled together for linear drive-mode oscillation along multi-directional drive axes in a plane formed by the first and second input axes. The masses are mounted on a generally planar sense frame for linear movements relative to the sense frame in drive-mode and for rotation together with the sense frame in sense modes. The sense frame is mounted for rotation with the masses in sense modes about the first, second, and third input axes independent of each other, in response to Coriolis forces produced by rotation of the masses about the first, second, and third input axes respectively. And capacitance sensors responsive to the rotational movements of the masses and the sense frame in sense modes are employed for monitoring rate of rotation.

An airfoil, and in a disclosed embodiment a rotor blade, has a serpentine cooling path. To best account for the Coriolis effect, the paths of the serpentine cooling channel have trapezoidal cross-sections. An area of the rotor blade between a smaller side of the trapezoidal-shaped paths, and a facing wall of the rotor blade has high thermal and mechanical stresses, and is a challenge to adequately cool. A microcircuit, which is a very thin cooling circuit having crossing pedestals, is embedded into the blade in this area. The microcircuit provides additional cooling, and addresses the challenges with regard to cooling these areas.

A micro-electromechanical systems (MEMS) transducer (400) is adapted to use lateral axis vibration of the drive mass (210) to generate non-planar oscillations of a coupling mass (220) in response to Coriolis forces created from in-plane rotational acceleration, which in turn generate non-planar motions of a symmetric teeter-totter sense mass (230) which are detected as a capacitive difference signal by capacitive electrodes (403, 404) formed on the substrate (402) below the sense mass (230).

A novel centrifuge bowl for processing particles suspended in a fluid is disclosed. The centrifuge bowl includes an annular cavity concentrically located about the rotation axis for suitably separating particles of similar densities but of different diameters. The cavity is preferably configured to have an annular cross sectional area, which is parallel to the rotation axis, that increases from a centrifugal side of the cavity toward a centripetal side of the cavity. This configuration allows to generate an almost rigidly rotating field upon rotation of the centrifuge bowl, which field helps to uniformly disperse Coriolis force throughout the circumference of the cavity to avoid turbulent mixing of the particles. In an alternative embodiment, the cavity is surrounded by an outer cavity for separating particles according to density before processing them through the inner cavity. This construction is particularly suitable for processing whole blood to harvest platelet-rich-plasma with reduced level of white blood cell contamination.

An angular rate sensor having two generally planar proof masses, a sense axis in the plane of the masses, and an input axis perpendicular to the sense axis. The masses are suspended from a driving frame, which is mounted for torsional movement about the input axis in drive-mode. And the masses are constrained for anti-phase movement along the sense axis in sense-mode in response to Coriolis forces produced by rotation of the masses about the input axis, with sensors responsive to the anti-phase movement of the masses along the sense axis for monitoring rate of rotation.