Patent classifications
G01C19/574
Method and system for control and readout of tuning fork gyroscope
A tuning fork sensor system places a controlled bias on the proof-mass drive-axis electrodes to cancel the quadrature charge. Also, its charge amplifiers employ a field-effect transistor biased slightly into the triode region so that it behaves as a very large value resistor. In addition, it uses a phase-locked loop having a special loop filter in order to optimize performance by rejecting off-frequency drive feedthrough to the motor pick-off while resulting in very low phase wander for the demodulation references.
Gyroscope with peripheral detection
A gyroscope comprises four Coriolis masses arranged around a center point where a lateral axis crosses a transversal axis orthogonally in the device plane. The first and second masses are aligned on the lateral axis, and the third and fourth masses are aligned on the transversal axis. The gyroscope further comprises four pairs of elongated mass elements. The mass elements of the first pair are transversally aligned on opposite sides of the lateral axis outside of the first mass. The mass elements of the second pair are transversally aligned on opposite sides of the lateral axis outside of the second mass. The mass elements of the third pair are laterally aligned on opposite sides of the first transversal axis outside of the third mass. The mass elements of the fourth pair are laterally aligned on opposite sides of the first transversal axis outside of the fourth mass.
Drive and sense stress relief apparatus
A MEMS device is provided comprising a mass configured to move along a first axis and a second axis substantially perpendicular to the first axis; a drive structure coupled to the mass and configured to cause the mass to move along the first axis; a sense structure coupled to the mass and configured to detect motion of the mass along the second axis; a stress relief structure coupled to one of the drive structure or the sense structure; and at least one anchor coupled to an underlying substrate of the MEMS device, wherein the stress relief structure is coupled to the at least one anchor and the at least one anchor is disposed outside of the stress relief structure.
ROTATION MEASUREMENT SYSTEM USING CORIOLIS AND EULER FORCES
A rotation measurement system that includes at least two proof masses and at least one pick-off is provided. Each proof mass is driven in a first axis of motion. The at least one pick-off is configured to measure movement of the at least two proof masses in a second axis when the system is rotated about a rotation point and generate Coriolis signals and Euler signals based on the measured movement of the at least two proof masses.
MEMS GYROSCOPE
The invention relates to the field of microelectromechanical systems (MEMS) gyroscopes. The MEMS gyroscope of the present invention drives oscillation of at least one proof mass in a primary drive mode at a first frequency and in a secondary drive mode at a second frequency, different to the first frequency. The primary drive mode and secondary drive mode are orthogonal. Sense circuitry measures oscillation of the at least one proof mass in a sense mode, which is orthogonal to the primary drive mode and the secondary drive mode, in order to determine the angular rate of rotation of the MEMS gyroscope about sense axes parallel to the movement of the at least one proof mass in the primary and secondary drive modes.
METHOD AND SYSTEM FOR CONTROL AND READOUT OF TUNING FORK GYROSCOPE
A tuning fork sensor system places a controlled bias on the proof-mass drive-axis electrodes to cancel the quadrature charge. Also, its charge amplifiers employ a field-effect transistor biased slightly into the triode region so that it behaves as a very large value resistor. In addition, it uses a phase-locked loop having a special loop filter in order to optimize performance by rejecting off-frequency drive feedthrough to the motor pick-off while resulting in very low phase wander for the demodulation references.
Synchronized four mass gyroscope
A gyroscope which comprises first and second proof masses aligned on a first lateral axis, third and fourth proof masses are aligned on a second lateral axis, and central and peripheral anti-phase coupling structures which synchronize a first and a second oscillation mode in this four-mass system. Each central x-axis anti-phase structure and each central y-axis anti-phase structure comprises an in-plane seesaw with a central elongated bar which is suspended from at least one central anchor point with at least one central seesaw suspender which allows the central elongated bar to rotate in the device plane about an axis which is perpendicular to the device plane.
Synchronized four mass gyroscope
A gyroscope which comprises first and second proof masses aligned on a first lateral axis, third and fourth proof masses are aligned on a second lateral axis, and central and peripheral anti-phase coupling structures which synchronize a first and a second oscillation mode in this four-mass system. Each central x-axis anti-phase structure and each central y-axis anti-phase structure comprises an in-plane seesaw with a central elongated bar which is suspended from at least one central anchor point with at least one central seesaw suspender which allows the central elongated bar to rotate in the device plane about an axis which is perpendicular to the device plane.
DOUBLE-LEVER COUPLING
A microelectromechanical resonator is provided with two proof masses that are coupled with an anti-phase coupling structure that includes a seesaw lever and a force-displacement lever. Moreover, a joint extends from the seesaw lever to the force-displacement lever and a mass connection element extends from each proof masse to the adjacent lever.
DOUBLE-LEVER COUPLING
A microelectromechanical resonator is provided with two proof masses that are coupled with an anti-phase coupling structure that includes a seesaw lever and a force-displacement lever. Moreover, a joint extends from the seesaw lever to the force-displacement lever and a mass connection element extends from each proof masse to the adjacent lever.