Patent classifications
G01C19/5755
Physical quantity sensor having a movable body formed with through-holes to reduce a difference between the inside-hole damping and the squeeze film damping
A physical quantity sensor includes a substrate, a movable body that faces the substrate, a fixed portion that is fixed to the substrate, and a support beam that couples the movable body to the fixed portion. The movable body is displaceable with the support beam as a rotation axis, and includes, in a plan view, a first mass that is located on one side of a second direction with respect to the rotation axis, and a second mass that is located on the other side. Each of the first mass and the second mass has a plurality of through-holes which penetrate through the movable body and each of which has a square shape as an opening shape. When damping is indicated by C, and a minimum value of the damping is indicated by Cmin, C1.5Cmin.
Gyroscope in-field prognostics
A method for determining an operational characteristic of a vibrating structure gyroscope having a movable mass includes: driving the mass to oscillate along a first, predefined path; rotating the vibrating structure gyroscope so as to oscillate the mass along a second path, wherein the second path is different to the first, predefined path; sensing the oscillation of the mass along the second path so as to generate a sensing signal; converting the sensing signal into an in-phase signal and an out-of-phase signal using a demodulator, wherein the in-phase signal is in phase with the oscillation of the mass along the first path, and the out-of-phase signal is out of phase with the in-phase signal.
Gyroscope in-field prognostics
A method for determining an operational characteristic of a vibrating structure gyroscope having a movable mass includes: driving the mass to oscillate along a first, predefined path; rotating the vibrating structure gyroscope so as to oscillate the mass along a second path, wherein the second path is different to the first, predefined path; sensing the oscillation of the mass along the second path so as to generate a sensing signal; converting the sensing signal into an in-phase signal and an out-of-phase signal using a demodulator, wherein the in-phase signal is in phase with the oscillation of the mass along the first path, and the out-of-phase signal is out of phase with the in-phase signal.
MEMS gyroscope with improved rejection of a quadrature error
A MEMS gyroscope is equipped with: at least a first mobile mass suspended from the top of a substrate by means of elastic suspension elements coupled to anchor points rigidly fixed to the substrate, in such a manner as to be actuated in an actuating movement along a first axis of a horizontal plane and to carry out a measurement movement along a vertical axis, transverse to the horizontal plane, in response to a first angular velocity acting about a second axis of the horizontal plane, transverse to the first axis. The elastic suspension elements are configured in such a manner as to internally compensate unwanted displacements out of the horizontal plane along the vertical axis originating from the actuating movement, such that the mobile mass remains in the horizontal plane during the actuating movement.
MEMS gyroscope with improved rejection of a quadrature error
A MEMS gyroscope is equipped with: at least a first mobile mass suspended from the top of a substrate by means of elastic suspension elements coupled to anchor points rigidly fixed to the substrate, in such a manner as to be actuated in an actuating movement along a first axis of a horizontal plane and to carry out a measurement movement along a vertical axis, transverse to the horizontal plane, in response to a first angular velocity acting about a second axis of the horizontal plane, transverse to the first axis. The elastic suspension elements are configured in such a manner as to internally compensate unwanted displacements out of the horizontal plane along the vertical axis originating from the actuating movement, such that the mobile mass remains in the horizontal plane during the actuating movement.
Sensor device employing MEMS
According to one embodiment, a sensor device includes a movable body capable of vibrating, and a catch-and-release mechanism capable of catching the vibrating movable body and capable of releasing the caught movable body. The catch-and-release mechanism includes a stopper portion capable of stopping vibration of the movable body when the movable body contacts the stopper portion, and an elastic member configured to reduce a force acting between the movable body and the stopper portion.
Sensor device employing MEMS
According to one embodiment, a sensor device includes a movable body capable of vibrating, and a catch-and-release mechanism capable of catching the vibrating movable body and capable of releasing the caught movable body. The catch-and-release mechanism includes a stopper portion capable of stopping vibration of the movable body when the movable body contacts the stopper portion, and an elastic member configured to reduce a force acting between the movable body and the stopper portion.
MEMS out of plane actuator
A MEMS sensor device comprises a support substrate, a proof mass movably connected to the support substrate, a first drive comb fixedly connected to the support substrate in a first orientation and adjacent to the proof mass, and a second drive comb fixedly connected to the support substrate in a second orientation and adjacent to the proof mass. The second orientation is opposite of the first orientation such that the first and second drive combs face toward each other. A parallel plate sense electrode is located under the proof mass on the support substrate. The drive combs and the parallel plate sense electrode are each electrically charged and configured with respect to the proof mass such that a combination of a levitation force and a parallel plate force produces a linear out-of-plane actuation that depends only on an applied voltage.
MEMS out of plane actuator
A MEMS sensor device comprises a support substrate, a proof mass movably connected to the support substrate, a first drive comb fixedly connected to the support substrate in a first orientation and adjacent to the proof mass, and a second drive comb fixedly connected to the support substrate in a second orientation and adjacent to the proof mass. The second orientation is opposite of the first orientation such that the first and second drive combs face toward each other. A parallel plate sense electrode is located under the proof mass on the support substrate. The drive combs and the parallel plate sense electrode are each electrically charged and configured with respect to the proof mass such that a combination of a levitation force and a parallel plate force produces a linear out-of-plane actuation that depends only on an applied voltage.
High dynamic range gyroscope
A sensor includes an acceleration or magnetic field sensitive microelectromechanical systems (MEMS) resonator, configured to oscillate in at least a first normal mode and a second normal mode. The sensor further includes: a coarse readout circuit configured to drive the first normal mode, measure a motion of the first normal mode, and derive from the measured motion a coarse measurement of the true acceleration or true external magnetic field; and a fine readout circuit configured to drive the second normal mode, measure a motion of the second normal mode, and derive from the measured motion and the coarse measurement a measurement of the difference between the true acceleration or true external magnetic field and the coarse measurement.