50 results about "Proof mass" patented technology

An accelerometer including: a housing; a proof mass; a piezoelectric material; a support member for holding the proof mass a predetermined distance from the piezoelectric material, the proof mass being rotatably disposed relative to the housing and having a center of gravity offset from an axis of rotation of the support member; a first biasing material for biasing the proof mass towards the piezoelectric material and against the support member; and a second biasing material for biasing the proof mass at the predetermined distance from the piezoelectric material. When a level of acceleration of the proof mass is less than or equal to an acceleration level that is to be measured, the second biasing material is configured to force the support member to rotate to disengage the proof-mass and the first biasing material to move the proof-mass to contact the piezoelectric material.

Embodiments of the present disclosure provide a fully decoupled three-axis MEMS gyroscope and an electronic product. The gyroscope comprises: a substrate, and an X / Y proof mass, Z proof masses, driving structures and Z decoupling masses that are fixed on the substrate; the X / Y proof mass is arranged around outer sides of the Z proof masses, the driving structures and the Z decoupling masses; the Z proof masses are oppositely arranged in an x-axis direction; the driving structures are oppositely arranged at outer sides of the Z proof masses in the x-axis direction; and the Z decoupling masses are oppositely arranged at inner sides of the Z proof masses in the x-axis direction. The X / Y proof mass is elastically connected to the driving structures adjacent thereto, the Z proof masses are elastically connected to the driving structures adjacent thereto, and the Z decoupling masses are elastically connected to the Z proof masses adjacent thereto. The gyroscope improves the Coriolis conversion rate of the X / Y proof mass, maximizes the utilization of the chip area, reduces chip size and cost, and reduces coupling errors and quadrature errors, thereby improving sensing accuracy.

An algorithm and architecture for sense transfer function estimation injects one or more test signals from a signal generator into a MEMS gyroscope to detect an output signal (e.g., proof mass output sense signal), including an in-phase (e.g., Coriolis) component and a quadrature component. The in-phase and quadrature components are encoded with reference signals to determine phase and / or gain variation and are processed via a variety of components (e.g., matrix rotation, digital gain, tones demodulator, transfer function errors estimation, etc.) to estimate a sense transfer function of the MEMS (e.g., Hs(fd)) and corresponding phase and / or gain offset of Hs(fd). The in-phase and quadrature components are also compensated for phase and / or gain offset by system components.

The invention discloses an accelerometer system, and the accelerometer system comprises a first magnetic assembly which comprises a first pole shoe; the second magnetic assembly comprises a second pole shoe, and the physical shape of the second pole shoe is different from that of the first pole shoe; and a proof mass assembly, the proof mass assembly comprising: a proof mass, the proof mass being between the first magnetic assembly and the second magnetic assembly. A first magnetic flux flows from the first magnetic assembly to the first pole shoe, wherein an amount of the first magnetic flux through the first coil is based on the physical shape of the first pole shoe; a second magnetic flux flows from the second magnetic assembly to the second pole shoe, and wherein a magnitude of the second magnetic flux is based on the physical shape of the second pole shoe.

The invention provides an accelerometer. The accelerometer comprises a base, a sensing unit arranged on the base and two anchor points for fixing the base, the sensing unit comprises an outer coupling unit which is stacked on the base; the number of the seesaw structures is two, the two seesaw structures are arranged on the inner side of the outer coupling unit, and the two seesaw structures are arranged in a central symmetry mode; the number of the inner side coupling units is two, the inner side coupling units are arranged on the inner side of the outer side coupling unit, and the two inner side coupling units are symmetrically arranged relative to a connecting line of the two anchor points; the test mass block is fixed on the outer side coupling unit and / or the inner side coupling unit; the accelerometer further comprises out-of-plane detection devices, and the out-of-plane detection devices are respectively arranged in a base area directly facing the outer side coupling unit and a base area directly facing the inner side coupling unit. According to the accelerometer, all displacement of the out-of-plane detection capacitor can be changed into linear displacement, and the linearity of acceleration detection is greatly improved.

We provide a system that includes a MEMS gyroscope with reduced scale factor drift. [Solution] The system comprises a micro-electromechanical system (MEMS) gyroscope including a vibrating proof mass, and readout electronics coupled to the MEMS gyroscope, the readout electronics including a first electrical channel that monitors the amplitude of vibration of the proof mass at a first frequency and generates a drive output, and a second electrical channel that monitors the amplitude of the proof mass's response to an input rate representing the deflection of the proof mass and generates a rate output. The processing system includes a signal generator that generates a test tone at a second frequency different from the first frequency and outside the bandwidth of the MEMS gyroscope and injects it into the first and second electrical channels, and a scale factor adjustment function that adjusts the scale factor of the MEMS gyroscope by the ratio of the drive output at the second frequency to the rate output at the second frequency.

A round robin MEMS sensor system includes multiple sensor types connected to a shared sense path in which measurement and evaluation operations are performed in a round robin fashion. Signals corresponding to movement of a proof mass are selectively provided to measurement circuitry, and in turn, the output of the measurement circuitry is selectively provided to the evaluation circuitry. The timing of these operations is optimized such that numerous MEMS sensor and other sensor outputs can be evaluated through the common sense path without sacrificing sensor accuracy or speed.

An inertial sensor such as a MEMS accelerometer or gyroscope has a proof mass that is driven by a self-test signal, with the response of the proof mass to the self-test signal being used to determine whether the sensor is within specification. The self-test signal is provided as a non-periodic self-test pattern that does not correlate with noise such as environmental vibrations that are also experienced by the proof mass during the self-test procedure. The sense output signal corresponding to the proof mass is correlated with the non-periodic self-test signal, such that an output correlation value corresponds only to the proof mass response to the applied self-test signal.

The application provides a free degree decoupling electrostatic accelerometer, belonging to the field of acceleration sensing test, comprising: a sensitive probe, a capacitive displacement sensing circuit, a feedback electrostatic actuator, a PID controller, a DAC circuit and a bias voltage driver; the surface of a proof mass is separated into several independent parts, the DAC circuit applies positive and negative amplitude analog bias voltage to the proof mass respectively; the bias voltage applied on the opposite surfaces of the proof mass is equal in size and opposite in sign; the capacitive displacement sensing circuit tests the position of the proof mass in the sensitive probe; the PID controller calculates a feedback voltage to control the capacitive plate; and the feedback electrostatic actuator applies the feedback voltage to the capacitive plate to generate a feedback force. The conventional electrostatic accelerometer needs to use a plus-minus combination circuit to obtain the free degree information, and the electrostatic accelerometer has the ability of free degree decoupling.

The utility model discloses a quartz flexible accelerometer with small -size swing piece, include: shell, two magnetic component and swing piece, mounting ring is set between the shell and swing piece, the electromagnetic board is set to the mounting ring outer wall, mounting frame is provided with two groups, all set in the swing piece eaves position department, and symmetrical design, correct component is provided with two, and respectively set in corresponding mounting frame inner wall, be used for the clamping fixed of swing piece on swing tongue, the utility model discloses due to adopt the design scheme of small -size swing piece structure, under the auxiliary action of mounting frame, when not using quartz flexible accelerometer, through torsional spring, lever, triangular block can fix swing tongue on swing piece, can effectively prevent swing tongue overhanging end droop, thereby can realize the efficacy of horizontal correction.

A gyroscope includes a substrate, a proof mass coupled to the substrate and configured to move in direction of an X axis and in direction of a Y axis orthogonal to the first axis, an X axis shuttle to selectively drive the proof mass along the X axis as a drive axis or sense movement of the proof mass along the X axis as a sense axis in response to the proof mass driven along the Y axis as the drive axis, and a Y axis shuttle to selectively sense movement of the proof mass along the Y axis as a sense axis in response to the proof mass driven along the X axis or drive the proof mass along the Y axis as the drive axis. The X axis shuttle is symmetric to the Y axis shuttle along a diagonal axis that is diagonal to both the X axis and the Y axis. The X and Y axis shuttles have gaps designed for a predetermined DC voltage to generate spring softening (negative cubic nonlinearity) that is equal to spring hardening (positive cubic nonlinearity), ensuring linear motion at high amplitudes (⅓ of the capacitive gap).

The present invention relates to coupling folded springs in a microelectromechanical system (MEMS) device. A MEMS device is described, comprising a proof mass movably connected to a substrate via folded springs disposed on opposite sides of the proof mass, wherein a coupler couples two of the folded springs together. In some embodiments, the coupler is a rod and can be rigid. Thus, the coupler constrains the relative motion of the folded springs. In this manner, the motion of the proof mass can be constrained to a preferred type and frequency.

A single-axis pendulum accelerometer having a plurality of anchors is disclosed. The plurality of anchors may be arranged around a rotation axis of a pendulum proof mass. Each of the plurality of anchors may be coupled to the proof mass by two torsion springs each extending along the rotation axis. The plurality of anchors allows an increased number of torsion springs coupled to the proof mass, and thus a greater torsional stiffness of the proof mass may be achieved. Due to the higher torsional stiffness, the disclosed single-axis pendulum accelerometer may be deployed in high frequency environments, such as about 20 kHz and above, where increased torsional stiffness is desired.

Angular accelerometers are described, as are systems employing such accelerometers. The angular accelerometers may include a proof mass and rotational acceleration detection beams directed toward the center of the proof mass. The angular accelerometers may include sensing capabilities for angular acceleration about three orthogonal axes. The sensing regions for angular acceleration about one of the three axes may be positioned radially closer to the center of the proof mass than the sensing regions for angular acceleration about the other two axes. The proof mass may be connected to the substrate though one or more anchors.

The present disclosure relates to apparatuses, systems, and techniques for determining acceleration of a vibrating beam accelerometer (VBA). For example, a system includes processing circuitry configured to receive, from a first resonator, one or more electrical signals indicative of a frequency of a first mechanical beam and a frequency of a second mechanical beam, determine, based on the one or more electrical signals, the frequency of the first mechanical beam and the frequency of the second mechanical beam, and calculate, based on the frequency of the first mechanical beam and the frequency of the second mechanical beam, an acceleration of a proof mass assembly.

A microelectromechanical system (MEMS) accelerometer includes a proof mass that translates outside of a MEMS device plane in response to a force of interest such as a z-axis linear acceleration. The proof mass is a component of a suspended spring-mass system that is anchored to both a cover substrate layer and a base substrate layer by an anchoring system. The anchoring system includes a central anchor that is mechanically anchored to only the cover layer, while two adjacent anchors are located at opposite sides of the central anchor and are anchored to at least the base substrate and have an electrical connection to processing circuitry of the base substrate. Compliant springs connect the central anchor to the two adjacent anchors in a manner such that the anchoring system absorbs applied stresses such as shear forces applied during system packaging, assembly, and during use in an end product.

The present invention discloses a method for constructing a photocurrent model of an inertial sensor, including: establishing a photocurrent model based on the general equation of photocurrent on a metal surface and the geometric structure of the inertial sensor; respectively calibrating the parameters of the photocurrent model: obtaining the number of photoelectron emissions in each divided area of the inner surface of the inertial sensor according to the optical characteristics; regulating the potential difference between each electrode plate and the proof mass to make the state between the electrode plate and the proof mass in the saturation state and the zero state, and respectively measuring the photocurrent in these two mode combinations, and obtaining the shunt probability between all the electrode plates and the proof mass according to the photocurrent in the two mode combinations; measuring the photocurrent of the proof mass from the negative saturation state potential to the positive saturation state potential, and inversely solving the photoelectron migration probability of the inertial sensor from the photocurrent model equation. The present invention can accurately give the influence of the potential of each electrode plate in the inertial sensor on the discharge performance of the proof mass, and assist in designing the discharge strategy of the charge management system.

A MEMS inertial sensor device, method of operation, and fabrication process are described wherein a MEMS inertial sensor and drive actuation units are coupled together in operational engagement, where the MEMS inertial sensor includes a substrate and a proof mass array positioned in spaced apart relationship above a surface of the substrate and constructed with a plurality of proof mass sub-structures which are each separately connected to the substrate with orthogonally disposed pairs of spring suspension structures and which are each rigidly connected to one or more adjacent proof mass sub-structures with one or more connector bars so that the plurality of proof mass sub-structures move as a single proof mass array that can operate at resonant frequencies of at least 100 kHz when oscillating in first and second orthogonal directions.

A dual axis accelerometer with a single proof mass measures in-plane acceleration (e.g., either along an x-axis or a y-axis), out-of-plane acceleration (e.g., normal to an x-y plane), and tilt of a fixed portion of a MEMS layer (e.g., normal to the x-y plane). In response to a tilt measurement, the dual-axis accelerometer compensates any offset (e.g., variability) of the out-of-plane accelerometer in order to maintain offset stability. In some embodiments, multiple dual axis accelerometers, perpendicularly configured, may be implemented via processing circuitry to offer three axis sensitivity capability.

The application is directed to a MEMS acousto-optic accelerometer for the detection and measurement of acceleration. The accelerometer is fabricated of optical quality materials using MEMS processing techniques on a substrate. It is comprised of a Bragg cell, proof mass, hinge, light source, and an optical detector. The proof mass of the accelerometer is attached to the substrate by a hinge that allows for pendulous motion under applied acceleration. The Bragg cell is anchored to the proof mass and to the substrate in such a way as to oppose the pendulous motion. The light source is coupled to the Bragg cell whose output is sensed by the optical detector. Force created by the proof mass and acceleration causes a change in the vibrational frequency of the Bragg cell resulting in a change in the frequency of the light sensed by the optical detector, which provides observability of the applied acceleration.

An accelerometer system includes a housing including a first portion and a second portion, the housing having a first coefficient of thermal expansion (CTE) value; and a proof mass element disposed between the first portion and the second portion of the housing, where a first surface of the proof mass element contacts the first portion and a second surface of the proof mass element contacts the second portion, the proof mass element having a second CTE value that differs from the first CTE value by within 30% of the first CTE value.

The present application belongs to the field of electrostatic accelerometers, and specifically discloses an electrostatic accelerometer and a zero position adjustment method thereof, the method comprising: when the external acceleration acting on the capacitor plate is an acceleration in a first direction, adjusting the control zero position of the test mass to a first position range; when the external acceleration acting on the capacitor plate is an acceleration in a second direction, adjusting the control zero position of the test mass to a second position range; wherein, the first position range is the position of the test mass when the distance of the test mass relative to the first capacitor plate is less than the distance of the test mass relative to the second capacitor plate, and the second position range is the position of the test mass when the distance of the test mass relative to the first capacitor plate is greater than the distance of the test mass relative to the second capacitor plate; the position of the test mass is the distance between the center of the test mass and the axis of symmetry of the two capacitor plates. Through this application, the present application effectively improves the range of the electrostatic accelerometer on the basis of the traditional electrostatic accelerometer.

This application belongs to the field of precision measurement, and specifically discloses a device and method for measuring the surface potential of a test mass based on a milligram-level torsion balance. Through this application, a milligram-level torsion balance is used instead of the traditional torsion balance. Compared with the traditional torsion balance, the milligram-level torsion balance has a smaller moment of inertia, lower torque-sensing thermal noise, and a torque detection level better than 10<supgt;‑18< / supgt> Nm / Hz<supgt;0.5< / supgt>, with extremely high detection sensitivity; a micrometer-level charged microsphere is used instead of the source conductor probe as the excitation source, and the spatial resolution can reach the micrometer level. Since the charged microsphere in suspension has a small charge amount and a small volume, the influence on the surface potential of the test mass to be measured is small and can be ignored, taking into account a relatively high spatial resolution; an optical module is used instead of the micro-displacement platform to provide the optical trap gradient force for the suspension of the charged microsphere and change the position of the suspended charged microsphere so that it faces different regions of the test mass surface. The suspended microsphere only interacts with photons, reducing the mechanical contact between the microsphere and other objects, reducing the friction effect, and improving the detection accuracy.

Provided are a fully-decoupled three-axis MEMS gyroscope and an electronic product. The gyroscope includes a substrate, an X / Y proof mass, Z proof masses, driving structures, and Z decoupled masses fixed to the substrate. The X / Y proof mass is annularly arranged outside the Z proof masses, the driving structures, and the Z decoupled masses; the X / Y proof masses are arranged oppositely along an x-axis direction; the driving structures are arranged oppositely along the x-axis direction outside the Z proof masses; and the Z decoupled masses are arranged oppositely along the x-axis direction at inner sides of the Z proof masses. The X / Y proof mass is elastically connected to the driving structures adjacent thereto, each Z proof mass is elastically connected to one driving structure adjacent thereto, and each Z decoupled mass is elastically connected to one Z proof mass adjacent thereto. The gyroscope has improved detection precision.

An accelerometer system including: a housing comprising a first portion and a second portion, the housing has a first coefficient of thermal expansion (CTE) value; and a proof mass element disposed between the first portion and the second portion of the housing, wherein a first surface of the proof mass element contacts the first portion and a second surface of the proof mass element contacts the second portion, the proof mass element having a second CTE value, the second CTE value being within 30% of the first CTE value.

The present application provides an electrostatic accelerometer for reducing measurement errors based on data fusion, which belongs to the field of acceleration sensor testing; the electrostatic accelerometer includes: a sensitive probe, a measurement control module and a data processing module; one end of the sensitive probe is connected to the measurement control module; the measurement control module is connected to the data processing module; the measurement control module is used to collect the displacement of the inspection mass in the sensitive probe, and convert the displacement signal into a feedback voltage signal and apply it to the capacitor plate in the sensitive probe to generate an electrostatic force; the data processing module is used to collect the feedback voltage signal in the measurement control module and the residual voltage related to the inspection mass displacement and perform analog-to-digital conversion and then fuse it, compensate for the input acceleration measurement error term related to the relative position, and extract the measurement result of the external input acceleration. The present application improves the measurement speed of the electrostatic accelerometer.

A micro-electromechanical device of the inertial sensor type, includes a support, a movable frame, translationally guided along an axis of displacement parallel to the support, and including a proof mass which extends from a first end, connected to the support through a mechanical link, up to a second end, the mass being connected, on the side of the second end, to a member for detecting pivoting of the mass with respect to the frame. The link includes a thin, flexible wall which extends parallel to the support, from the frame to the first end of the proof mass, along a mean line which is parallel to the axis of displacement of the frame.

An accelerometer comprising a first proof mass and a second proof mass which are coupled to each other with a coupling structure which extends from the first proof mass to the second proof mass. The coupling structure synchronizes the movement of the first and second proof masses so that the first and second proof masses may be linearly displaced from their rest position in the x-direction, rotationally displaced in opposite in-plane directions and rotationally displaced in opposite out-of-plane directions.

A design calculation and use method of a retarder mass block assembly for indirectly measuring dynamic stiffness transmitted by a multi-type flexible pipe, wherein the retarder mass block assembly is designed according to basic parameters of the flexible pipe to be measured and a required effective test frequency range (f min , f max ), the upper and lower limits of the mass of the retarder mass block are determined, and the retarder mass block assembly and the retarder mass block unit are selected. The retarder mass block assembly mainly comprises the retarder mass block unit and connecting fasteners, the retarder mass block assembly is connected with the transition element, the flexible pipe to be measured and the excitation element by the connecting fasteners respectively, and axial measurement and transverse measurement of the indirectly measured dynamic stiffness are completed. By using combinations of different retarder mass block unit assemblies, the measurement requirements of dynamic stiffness transmitted by multi-type flexible pipes can be met without changing the overall structure of the measurement rack.

The invention provides a capacitance displacement sensing zero offset calibration and compensation method, which comprises the following steps of: adding a compensation signal and a calibration signal into a servo control system of electrostatic suspension capacitive inertial measurement equipment, and calibrating and compensating the capacitance displacement sensing zero offset in a closed-loop state. The method comprises the following steps: by utilizing a nonlinear effect caused by capacitance displacement sensing zero offset, actively applying a calibration signal modulated by a sine carrier trapezoidal wave to a test mass block, analyzing a quadratic term nonlinear response of an output signal of a measurement system controller, and calculating to obtain a capacitance displacement sensing zero offset value according to the nonlinear response; and a compensation signal corresponding to the zero-bias anti-phase value is directly applied to the input end of the system controller, so that the zero-bias compensation of the capacitance displacement sensor is realized. By using the method, the capacitance displacement sensing zero offset generated by a system full link can be calibrated and compensated in a closed-loop state.