G01C19/5726

RESONANT SENSOR USING MEMS RESONATOR, AND DETECTION METHOD BY RESONANT SENSOR
20230048120 · 2023-02-16 ·

A temperature sensor is a temperature sensor using a MEMS resonator, and includes: a MEMS resonator; a sweeper that sweeps a frequency of an excitation signal for a vibrator of the MEMS resonator in a predetermined sweep direction, and outputs the excitation signal swept to the MEMS resonator; a discontinuity point detector that obtains a vibration state information signal, which is a characteristic quantity expressing a vibration state of the vibrator based on the excitation signal, from the MEMS resonator, and detects a detection value that is (i) a frequency of the excitation signal when the vibration state information signal obtained changes discontinuously or (ii) a time corresponding to the frequency; and a converter that determines a physical quantity acting on the MEMS resonator based on the detection value detected.

MICROELECTROMECHANICAL GYROSCOPE WITH COMPENSATION OF QUADRATURE SIGNAL COMPONENTS
20180003504 · 2018-01-04 ·

A gyroscope includes: a mass, which is movable with respect to a supporting body; a driving loop for keeping the mass in oscillation according to a driving axis; a reading device, which supplying an output signal indicating an angular speed of the body; and a compensation device, for attenuating spurious signal components in quadrature with respect to a velocity of oscillation of the mass. The reading device includes an amplifier, which supplies a transduction signal indicating a position of the mass according to a sensing axis. The compensation device forms a control loop with the amplifier, extracts from the transduction signal an error signal representing quadrature components in the transduction signal, and supplies to the amplifier a compensation signal such as to attenuate the error signal.

MICROELECTROMECHANICAL GYROSCOPE WITH COMPENSATION OF QUADRATURE SIGNAL COMPONENTS
20180003504 · 2018-01-04 ·

A gyroscope includes: a mass, which is movable with respect to a supporting body; a driving loop for keeping the mass in oscillation according to a driving axis; a reading device, which supplying an output signal indicating an angular speed of the body; and a compensation device, for attenuating spurious signal components in quadrature with respect to a velocity of oscillation of the mass. The reading device includes an amplifier, which supplies a transduction signal indicating a position of the mass according to a sensing axis. The compensation device forms a control loop with the amplifier, extracts from the transduction signal an error signal representing quadrature components in the transduction signal, and supplies to the amplifier a compensation signal such as to attenuate the error signal.

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.

SENSOR SYSTEM AND METHOD FOR COMPENSATING FOR AN OFFSET OF AN ANGULAR RATE SIGNAL
20230213340 · 2023-07-06 ·

A sensor system. The sensor system comprises a MEMS gyroscope, comprising at least: a seismic mass, which can be excited to vibrate and has at least one electrode assembly for capacitively detecting a measurement signal, a drive circuit for generating a drive voltage for exciting and maintaining a defined vibratory movement of the seismic mass, there being a parasitic capacitive coupling between the drive circuit and the at least one electrode assembly, a detection circuit for reading out the measurement signal and for generating an angular rate signal on the basis of the measurement signal, characterized by circuitry means for compensating for an offset of the angular rate signal on the basis of the drive voltage.

SENSOR SYSTEM AND METHOD FOR COMPENSATING FOR AN OFFSET OF AN ANGULAR RATE SIGNAL
20230213340 · 2023-07-06 ·

A sensor system. The sensor system comprises a MEMS gyroscope, comprising at least: a seismic mass, which can be excited to vibrate and has at least one electrode assembly for capacitively detecting a measurement signal, a drive circuit for generating a drive voltage for exciting and maintaining a defined vibratory movement of the seismic mass, there being a parasitic capacitive coupling between the drive circuit and the at least one electrode assembly, a detection circuit for reading out the measurement signal and for generating an angular rate signal on the basis of the measurement signal, characterized by circuitry means for compensating for an offset of the angular rate signal on the basis of the drive voltage.

DRIVING CIRCUIT FOR CONTROLLING A MEMS OSCILLATOR OF RESONANT TYPE

A driving circuit for controlling a MEMS oscillator includes a digital conversion stage to acquire a differential sensing signal indicative of a displacement of a movable mass of the MEMS oscillator, and to convert the differential sensing signal of analog type into a digital differential signal of digital type. Processing circuitry is configured to generate a digital control signal of digital type as a function of the comparison between the digital differential signal and a differential reference signal indicative of a target amplitude of oscillation of the movable mass which causes the resonance of the MEMS oscillator. An analog conversion stage includes a ΣΔ DAC and is configured to convert the digital control signal into a PDM control signal of analog type. A filtering stage of low-pass type, by filtering the PDM control signal, generates a control signal for controlling the amplitude of oscillation of the movable mass.

DRIVING CIRCUIT FOR CONTROLLING A MEMS OSCILLATOR OF RESONANT TYPE

A driving circuit for controlling a MEMS oscillator includes a digital conversion stage to acquire a differential sensing signal indicative of a displacement of a movable mass of the MEMS oscillator, and to convert the differential sensing signal of analog type into a digital differential signal of digital type. Processing circuitry is configured to generate a digital control signal of digital type as a function of the comparison between the digital differential signal and a differential reference signal indicative of a target amplitude of oscillation of the movable mass which causes the resonance of the MEMS oscillator. An analog conversion stage includes a ΣΔ DAC and is configured to convert the digital control signal into a PDM control signal of analog type. A filtering stage of low-pass type, by filtering the PDM control signal, generates a control signal for controlling the amplitude of oscillation of the movable mass.

High stability angular sensor

An angular rate sensor. The sensor includes a Coriolis vibratory gyroscope (CVG) resonator, configured to oscillate in a first normal mode and in a second normal mode; a frequency reference configured to generate a reference signal; and a first phase control circuit. The first phase control circuit is configured to: measure a first phase difference between: a first phase target, and the difference between: a phase of an oscillation of the first normal mode and a phase of the reference signal. The first phase control circuit is further configured to apply a first phase correction signal to the CVG resonator, to reduce the first phase difference. A second phase control circuit is similarly configured to apply a second phase correction signal to the CVG resonator, to reduce a corresponding, second phase difference.

ROTATION MEASUREMENT SYSTEM USING CORIOLIS AND EULER FORCES
20230057613 · 2023-02-23 · ·

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.