Abstract: A method and system for estimating the inception of gimbal motion of an inertial measurement unit (IMU), includes independently filtering, in a computer process, three-axis angular orientation rate information or data from component gyroscopes in the IMU, to provide a first output; adaptively detecting, in another computer process, discontinuities in the first output; estimating a regularity of gimbal motion to provide a second output; and comparing the discontinuities detected in the first output to the estimated regularity of gimbal motion provided in the second output, in another computer process, to determine which of the discontinuities detected in the first output are true discontinuities and which of the discontinuities in the first output that are false discontinuities, and to identify other discontinuities which have been missed in the first output. The true and missed discontinuities are estimates of the inception of gimbal motion of the IMU.

Abstract: A method for carrying out a functional analysis on a person equipped with an artificial extremity having adjustable settings. The method includes the steps of providing a sensor assembly configured as a replacement for a part of the artificial extremity and installing the sensor assembly in place of the part. Forces, accelerations and/or torques are then measured with the sensor assembly during use of the artificial extremity by the person and the settings of the artificial extremity are optimized based on these measurements. The sensor assembly is removed and the replaced part is installed back into the artificial extremity, while retaining the optimized settings. In one embodiment, the artificial extremity is a leg prosthesis having an artificial knee joint with a rotational adaptor mounted above it. The sensor assembly then replaces the rotational adaptor.

Abstract: Tuning an axisymmetric resonator such as in a disc resonator gyroscope (DRG) is disclosed. Frequency tuning a DRG in a single step informed by a systematic physical model of the resonator structure, sensing and actuation elements, such as a finite element model, is provided. The sensitivity of selected trimming positions on the resonator to reducing asymmetry terms is determined via perturbations of the systematic model. As well, the dependence of the parameters of model transfer functions between actuation and sensing elements on resonator asymmetry are systematically determined. One or two measured transfer functions may then be analyzed according to the systematic model to fully determine the needed asymmetry correction components of the DRG. One or two of four groups of four electrostatic bias electrodes or four groups of four laser trimming locations for the DRG are utilized to correct the asymmetry components which can give rise to mistuning.

Abstract: A downhole sensor calibration apparatus includes a rotational or gimbaling mechanism for guiding a sensing axis of an orientation responsive sensor through a three-dimensional orbit about three orthogonal axes. A method includes using measurements taken over the three-dimensional orbit to calibrate the sensor and determine other characteristics of the sensor or tool.

Abstract: The effects of IMU gyro and accelerometer bias errors are significantly reduced in accordance with the present teachings by a system or method for commanding an IMU or vehicle through a series of preprogrammed maneuvers. The maneuvers can be designed to minimize the effects of other gyro errors including scale factor errors, nonlinearities, cross coupling/misalignment, and scale factor asymmetries. A sample maneuver is provided which demonstrates performance based on a sequence of roll and yaw maneuvers resulting in zero build up of error at the end of a maneuver cycle period as a result of these errors. Modification of the system involves the addition of control logic to determine the maneuver period, maneuver rate, and vehicle orientation. No additional hardware beyond possible fuel required to perform the maneuver is required.

Abstract: The system includes a mobile vessel having a body axis and a steering mechanism. A three-axis gyroscope is mounted within the vessel. A three-axis magnetometer is mounted within the vessel. A programmable device communicates with the three-axis gyroscope, the three-axis magnetometer, and the steering mechanism. The three-axis gyroscope may include three single axis gyroscopes.

Abstract: Compensating for the misalignment of a navigation device with respect to a vehicle is described. In one example, the compensation is made by applying a high pass filter to a measured acceleration of the vehicle to produce a motion acceleration signal, weighting the motion acceleration signal with a measured steering rate of the vehicle, and deriving misalignment parameters for the navigation device with respect to the vehicle using the weighted motion acceleration signal.

Abstract: A shaker for enabling the testing of gyros and/or other devices for performance under realistic 6DOF motions. The shaker may be implemented as a hexapod, comprising a plate and six individually, simultaneously, and real-time controllable strut assemblies that are capable of extending and contracting linearly. The strut assemblies may comprise high-precision, linear electromagnetic actuators. The strut assemblies may also comprise high-precision non-contact sensors to sense the extension/contraction of the strut assemblies along their stroke length. In addition, the strut assemblies may comprise, at each end thereof, stiff, bendable flexures to attain the repeatable and linear motion required. The controller preferably has a control bandwidth of 1000 Hz or more, so that the motion of the plate can be precisely controlled to realize realistic 6DOF motions.

Abstract: A micro-electro-mechanical gyroscope includes a first mass, which is able to oscillate along a first axis with respect to a fixed body, an inertial sensor having a second mass constrained to the first mass so as to oscillate along a second axis in response to a rotation of the gyroscope, a driving device coupled to the first mass that forms a control loop for maintaining the first mass in oscillation at a resonance frequency, and a reading device that detects displacements of the second mass along the second axis, which includes a charge amplifier for converting charge packets supplied by the inertial sensor into a charge-integration signal, and a low-pass filter. A calibration stage enables modification of a voltage between the second mass and the fixed body so as to minimize a component at a frequency that is twice the resonance frequency in the charge-integration signal.

Abstract: In a gyroscopic system comprising at least four vibratory gyroscopes, a first measurement is provided by said vibratory gyroscope to be calibrated, and a second measurement is provided by a combination of the measurements from the other vibratory gyroscopes of the system. At the level of the vibratory gyroscope to be calibrated, an initial command is applied in order to command a change in position from a first vibration position (?1) to a second vibration position (?2). A calibrated scale factor value of the vibratory gyroscope to be calibrated is then determined on the basis of a calculated value in relation to the change in position, based on the period of time during which the initial command is applied, the initial command, an angular difference between the first and second vibration positions measured according to the first measurement and an angular difference between the first and second vibration positions measured according to the second measurement.

Abstract: A gyroscopic system comprises at least four vibratory gyroscopes capable of changing vibration position. A first measurement is provided by a gyroscope to be calibrated and a second measurement is provided by a combination of the respective measurements from the other gyroscopes of the system, these first and second measurements being carried out along the same measurement axis. The determination (12) of a measurement drift value between the first measurement and the second measurement is followed by a command (13) to change the vibration position of the gyroscope to be calibrated to another vibration position and a drift value is again determined. The vibration position change command and the determination of a drift value are repeated (14) K times, K being a positive integer. Then, a drift model is generated (15) as a function of the vibration position of the gyroscope to be calibrated on the basis of the drift values obtained.

Abstract: Novel techniques for estimating compass and gyroscope biases for handheld devices are disclosed. The handheld devices can include wireless phones, navigational devices and video gaming systems. The compass bias can be determined by causing a small movement of the handheld device and comparing the data obtained from the compass with the data obtained from the gyroscope. The gyroscope bias can be determined by obtaining a quaternion based angular velocity term of the handheld device when the accelerometer and compass data are reliable, and then comparing the angular velocity term to with the gyro data estimate the gyro bias. When the compass and/or the accelerometer data are unreliable, a previously determined quaternion angular velocity term is used, which was determined when the compass and the accelerometer were providing reliable data.

Abstract: The system includes a mobile vessel having a body axis and a steering mechanism. A three-axis gyroscope is mounted within the vessel. A three-axis magnetometer is mounted within the vessel. A programmable device communicates with the three-axis gyroscope, the three-axis magnetometer, and the steering mechanism. The three-axis gyroscope may include three single axis gyroscopes.

Abstract: A method for calibrating a rotational angle sensor having a rotor (12) coupled to a rotating shaft (10) in a manner which is faithful to the rotational angle, a stator (16), and a scanning means (14) arranged on the stator (16). The scanning means (14) scans a material measure of the rotor (12) and generates measured angle values associated with the rotational angle position of the rotor (12). A laser gyroscope (18) measures the angular velocity of the shaft (10). The signals from the laser gyroscope (18) which are dependent on the angular velocity of the shaft (10) are integrated over time with respect to the rotational angle. The measured angle values from the scanning means (14) are compared with reference angle values, and correction variables are formed from the differences. During measurement of the rotational angle, the measured angle values are corrected using the correction variable.

Abstract: Systems and methods may be used to determine gain compensation and/or bias compensation for gyroscopes in the field where access to specialized calibration tools is limited.

Abstract: A method for calibrating a gyratory compactor apparatus is provided. The gyratory compactor apparatus is of the type being configured to compact and impart an orbital motion to a sample in a mold that defines a mold axis and includes at least one actuator for imparting lateral displacement of the mold relative to a longitudinal axis of the gyratory compactor apparatus. The method includes the steps of imparting lateral orbital displacement of the mold relative to the gyratory compactor apparatus by actuation of the at least one actuator to thereby define a gyratory angle between the gyratory compactor apparatus and the mold axis, measuring the gyratory angle, and determining adjustments to actuation of the at least one actuator based on the measured gyratory angle and a target angle. An associated apparatus and method for calibrating the apparatus are also included.

Abstract: The invention concerns gyrometric measurement compensated as a function of the instantaneous internal temperature of a mechanical resonator in a gyrometric measurement device comprising a loop controlling the amplitude of the resonator vibration and a gyrometric loop delivering a gyrometric signal (S); the gain control (P) of the loop varies as a monotonous function, preferably increasing and of the first order, of the internal temperature of the resonator in a given range of temperature; during a calibrating step, a correspondence is established and stored between the values of the gyrometric scaling factor (Fe) and the gyrometric bias (S0) and the values of the gain control signal (F), that is F(P) and Q(P) respectively; in operation, the following operations are carried out: P?F(P), P?Q(P), and ??est=F(P)·S+Q(P) which is a more precise analog estimate, compensated as a function of the internal temperature of the resonator, of the mechanical rotation of the sensitive axis of the resonator.

Abstract: A synchronous signal processing circuit for a dual-axis vibratory rotation-rate sensor uses a hybrid analog/digital design to provide correction for parasitic quadrature errors by the addition of synthesized correction signals in the analog domain prior to digitization. Error correction, signal demodulation and data conversions are synchronized with a signal phase-locked to the measured motion of the vibratory mass. Similarly, cross-axis error correction signals are synthesized directly from the cross axis signals. Use of these precise phase references provides for various benefits in signal noise and error matching (tracking) over wide operation conditions.

Abstract: An aerial camera system including a plurality of main reels, a camera interface/safety reel and a stabilized camera head. The camera head is supported from main cables from the main reels with a safety reel cable providing power, data and video communication between the camera head and a main computer system. Each of the main reels, the camera interface/safety reel and the camera head are in communication with the main computer system, which controls the feeding and reeling in of the main cables. Further, the computer system controls the feeding and reeling in of the safety reel cable, which typically only follows the camera head as it moves in three-dimensional space, but may in emergency mode support the weight of the camera head and be used to slowly pull the camera head up and out of the way so that it does not interfere with any activity below the flight area.

Abstract: A system and method for separating bias instability of MEMS inertial instruments such as gyroscopes or accelerometers from the instrument signal, in which the inertial measurement instrument has an input axis and an output signal, and the bias instability has a frequency. The instrument is oscillated about an oscillation axis that is orthogonal to the input axis, at a frequency that is greater than the bias instability frequency. The instrument output signal is detected, and demodulated with a phase-sensitive detection method referenced to the instrument rotation.

Abstract: A motion estimation method and system for a mobile body are provided. The method includes: obtaining magnetic field information from compass information of the mobile body; comparing the magnetic field of the mobile body with a predetermined value and determining whether a position of the mobile body belongs to a specific region according to the comparison result; and estimating a direction of the mobile body by determining whether a compass azimuth angle is used for direction estimation of the mobile body according to the determination result.

Abstract: While calibrating the position of a robot having a gyro, the robot emits a beam of light to a target wall surface, and the position of a laser point on the target wall surface illuminated by the beam of light is measured. The measured position is obtained as an initial value (S10, S12), and a start of calibration is indicated (S14, S16). Then, a calibration period is reset (S18) and the timekeeping process of the calibration period starts. The values detected by the gyro are consecutively obtained by sampling for a predetermined calibration period (S20). If a disturbance occurs while the values are obtained, an alarm is output and calibration restarts. Once the calibration period elapses without any disturbance, a calibrated value is set or determined based on the detected values obtained during the calibration period (S26, S28).

Abstract: A method and apparatus for calibrating a gyro-sensor, by which a gyro-sensor can be calibrated using data which is obtained by measuring an angular velocity and a gyro output value of a moving body equipped with the gyro-sensor. The method includes measuring an angular velocity of a moving body and an average output value of the gyro-sensor when the moving body, equipped with the gyro-sensor, rotates, obtaining data about a characteristic equation of the gyro sensor using the measured angular velocity and the average output value and storing the data, and calibrating the gyro-sensor using the stored data about the characteristic equation.

Abstract: Inertial measurement system and method in which a gyroscope is periodically dithered about an axis perpendicular to its input axis, a signal from the gyroscope is delayed to provide a delayed signal which lags the gyroscope signal by one-half of the dithering period, and the delayed signal and the signal from the gyroscope are combined to provide an output signal from which the bias has been cancelled.

Abstract: System having one or more inertial sensors in which one or more of the sensor input axes are modulated in orientation about an axis substantially perpendicular to the input, or sensitive, axis of the sensor and, in some embodiments, by also enhancing the accuracy of such a system to provide improved signal to noise ratio and reduced sensitivity to errors in alignment of the sensor axes to the dither axes.

Abstract: The present invention provides the stress detection method for force sensor device with multiple axis sensor device and force sensor device employing this method, whose installation angle is arbitrary. The stress detection method includes, first and second force sensors whose detection axes are orthogonal to each other. When the detection axis of first force sensor forms angle ? with direction of detected stress Ax, and the stress component of direction perpendicular to direction of the detected stress Ax is Az, output Apx of the axis direction of first force sensor is found as Apx=?x (Ax×cos ?+Az×sin ?), and output Apz of the axis direction of the second force sensor is found as Apz=?z (Ax×sin ?+Az×cos ?), and, when ?x and ?z are detection sensitivity coefficients of first and second force sensors respectively, the detection sensitivity coefficient ?z of second force sensor is set as ?z=?x tan ?, and the detected stress Ax is found as Ax=(Apx?Apz)/?x(cos ??tan ?×sin ?).

Abstract: A positioning and calibration system are provided for use in calibrating a single or multi axis sensitive instrument, such as an inclinometer. The positioning system includes a positioner that defines six planes of tangential contact. A mounting region within the six planes is adapted to have an inclinometer coupled thereto. The positioning system also includes means for defining first and second flat surfaces that are approximately perpendicular to one another with the first surface adapted to be oriented relative to a local or induced reference field of interest to the instrument being calibrated, such as a gravitational vector. The positioner is positioned such that one of its six planes tangentially rests on the first flat surface and another of its six planes tangentially contacts the second flat surface. A calibration system is formed when the positioning system is used with a data collector and processor.

Abstract: For an observer equipped with a first azimuth data source responsive to a magnetic field to deliver first azimuth data, such as a compass, and with a second azimuth data source delivering second azimuth data and which is independent of magnetic fields, such as a gyroscope. The azimuth is determined by: analyzing the first and second azimuth data to determine whether a magnetic disturbance is present, and determining azimuth selectively on the basis of: the first azimuth data, the second azimuth data, or a combination of the first and second azimuth data, as a function of the result of the comparing step. In an embodiment, the choices of azimuth data source and events such as magnetic disturbances, sensor updates, types of trajectory deduced, are stored as a history sequence over successive time windows, by analogy with a DNA sequence, and is exploited for optimizing azimuth or navigation results.

Abstract: A positioning and calibration system are provided for use in calibrating a single or multi axis sensitive instrument, such as an inclinometer. The positioning system includes a positioner that defines six planes of tangential contact. A mounting region within the six planes is adapted to have an inclinometer coupled thereto. The positioning system also includes means for defining first and second flat surfaces that are approximately perpendicular to one another with the first surface adapted to be oriented relative to a local or induced reference field of interest to the instrument being calibrated, such as a gravitational vector. The positioner is positioned such that one of its six planes tangentially rests on the first flat surface and another of its six planes tangentially contacts the second flat surface. A calibration system is formed when the positioning system is used with a data collector and processor.

Abstract: An activity monitor is provided that corrects for the effects of motion external to the entity being monitored. For example, the activity monitor can overcome the effects of vehicular travel.

Abstract: An array of three-axis magnetometers used for dynamic magnetic anomaly compensation are located at the corners of a parallelopiped, with pairs of magnetometer outputs used to derive a magnetic anomaly gradient vector used to compensate a compass and/or the output of a gyroscope in an inertial management unit. The system may be used in a neutrally buoyant remotely operated vehicle to permit ascertaining of course and position in the absence of surface control signals.

Abstract: An offset diagnosing and correcting section obtains an offset correction value from an angular rate value obtained from detection signals produced from a plurality of angular rate sensors and a detection signal produced from an angular rate sensor when an automotive vehicle is in a stopped condition. The offset diagnosing and correcting section performs an offset correction for the angular rate value with reference to this offset correction value. A sensor sensitivity diagnosing section detects a turning condition of the automotive vehicle based on detection signals of the plurality of angular rate sensors, and diagnoses the sensitivity of the plurality of angular rate sensors based on offset corrected angular rate values of these angular rate sensors when the automotive vehicle is in a turning condition.

Abstract: The present invention provides the stress detection method for force sensor device with multiple axis sensor device and force sensor device employing this method, whose installation angle is arbitrary. The stress detection method includes, first and second force sensors whose detection axes are orthogonal to each other. When the detection axis of first force sensor forms angle ? with direction of detected stress Ax, and the stress component of direction perpendicular to direction of the detected stress Ax is Az, output Apx of the axis direction of first force sensor is found as Apx=?x (Ax×cos ?+Az×sin ?), and output Apz of the axis direction of the second force sensor is found as Apz=?z (Ax×sin ?+Az×cos ?), and, when ?x and ?z are detection sensitivity coefficients of first and second force sensors respectively, the detection sensitivity coefficient ?z of second force sensor is set as ?z=?x tan ?, and the detected stress Ax is found as Ax=(Apx?Apz)/?x(cos ??tan ?×sin ?).

Abstract: A yaw-rate sensor having a resonant driving frequency and a resonant Coriolis frequency. In addition, the yaw-rate sensor has at least one operating voltage, of which the resonant Coriolis frequency is a function. The resonant Coriolis frequency is adjusted to the resonant driving frequency with the aid of an adjustment voltage. A change in the resonant Coriolis frequency as a result of a change in the operating voltage may be compensated for, in that a suitably changed adjusting voltage may be produced from a compensation circuit.

Abstract: In a method for determining the zero-point error of a Coriolis gyro, the resonator of the Coriolis gyro has a disturbance force applied to it such that a change in the stimulation oscillation of the resonator is brought about. A change in the read oscillation of the resonator, caused by a partial component of the disturbance force, is extracted from a read signal which represents the read oscillation of the resonator as a measure of the zero-point error.

Abstract: A method for determination of the zero error of a Coriolis gyro. Appropriate disturbance forces are applied to the resonator of the Coriolis gyro such that at least one natural oscillation of the resonator is stimulated that differs from the stimulating and read oscillations. A change in a read signal which represents the read oscillation and results from the stimulation of the at least one natural oscillation is determined as a measure of the zero error.

Abstract: A method for reducing bias error in a Vibrating Structure Gyroscope having a vibrating structure, a primary drive for putting the vibrating structure into carrier mode resonance, a primary pick-off device for sensing carrier mode motion, a secondary pick-off for sensing response mode vibration of the vibrating structure in response to applied rotation rate, a secondary drive for applying a force to control the response mode motion, closed loop primary control loops for maintaining a fixed amplitude of motion at the primary pick-off device, for maintaining the drive frequency at the resonance maximum, and secondary control loops for maintaining a null at the secondary pick-off device.

Abstract: The method serves to compensates anisotropy in an inertial rotation sensor comprising a metallized vibrating bell (1) having a bias voltage applied thereto, the vibrating bell (1) having an edge (7) electrodes (5.1, 5.2), and the method comprises the steps of measuring, preferably by multiplexing, the anisotropy between the electrodes and of applying to the electrodes a fraction of the bias voltage that depends on the differences measured between the electrodes.

Abstract: Apparatus for measuring variation in scalefactor from a predetermined value for a vibrating structure gyroscope has a vibrating structure (R), fixed primary and fixed secondary drives (1, 13) for putting and maintaining the vibrating structure (R) in vibrating resonance, fixed primary and fixed secondary pick offs (2, 6) for detecting vibration of the vibrating structure (R), with the drives and pick offs (1, 13, 2, 6) being located radially around the vibrating structure (R), quadrature component and real component loop systems (7, 8), automatic gain control and phase locked loop systems (5, 22), a sin/cos pick off resolver (38) for receiving signals from the primary and secondary pick offs (2, 6) and for outputting signals to the quadrature component and real component loop systems (7, 8) and to the automatic gain control and phase locked loop systems (5, 22), a sin/cos drive resolver (37) for receiving output signals from the quadrature component and real component loop systems (7, 8) and from the automati

Abstract: A method for compensation of the zero error of a Coriolis gyro. The frequency of the read oscillation is modulated. The output signal from a rotation rate control loop or quadrature control loop for the Coriolis gyro is demodulated in synchronism with the modulation of the frequency of the read oscillation to obtain an auxiliary signal. The auxiliary signal is a measure of the zero error. A compensation signal is produced and passed to the input of the rotation rate control loop or quadrature control loop, with the compensation signal being controlled such that the magnitude of the auxiliary signal is as small as possible.

Abstract: Inertial measurement system and method in which a base is rotated about an input axis in accordance with a rotation to be measured, rotation about the input axis is sensed with one or more angular rate sensors, fixed bias offset is cancelled by dithering the sensors about an axis perpendicular to their sensing axes to vary the orientation of the sensing axes relative to the base in an oscillatory manner, and signals from the sensors are demodulated at the dithering frequency.

Abstract: A micro-gyroscope (10) having closed loop output operation by a control voltage (Vty), that is demodulated by a drive axis (x-axis) signal Vthx of the sense electrodes (S1, S2), providing Coriolis torque rebalance to prevent displacement of the micro-gyroscope (10) on the output axis (y-axis) Vthy˜0. Closed loop drive axis torque, Vtx maintains a constant drive axis amplitude signal, Vthx. The present invention provides independent alignment and tuning of the micro-gyroscope by using separate electrodes and electrostatic bias voltages to adjust alignment and tuning. A quadrature amplitude signal, or cross-axis transfer function peak amplitude is used to detect misalignment that is corrected to zero by an electrostatic bias voltage adjustment. The cross-axis transfer function is either Vthy/Vty or Vtnx/Vtx.

Abstract: In a method for monitoring a rotation rate sensor with a vibrational gyroscope which has a first input and a first output which form part of a primary control loop which excites the vibrational gyroscope by supplying an excitation signal to the first input at its natural frequency, where the vibrational gyroscope also has a second input and a second output which form part of a secondary control loop, where an output signal can be taken from the second output, said output signal being amplified and subjected to analog/digital conversion and then demodulated into an inphase component and a quadrature component. The components are filtered and are then modulated again and compiled to form a driver signal which is supplied to the second input. A rotation rate signal is derived from the inphase component, the inphase component and the quadrature component have a test signal added to them whose frequency brings about sidebands which are situated in the driver signal outside of the second control loop's passband.

Abstract: The present invention aims to present an angular velocity sensor having a self diagnosis function. An angular velocity sensor of the present invention includes a driving part for stably vibrating a driving part of a sensor element having a driver part and a detector part for detecting an angular velocity and detection means for detecting the angular velocity of the sensor element and obtains a self diagnosis signal for a malfunction by detecting a mechanical coupling signal obtained at the detection means.

Abstract: Quadrature error occurs in vibrating gyroscopes because of manufacturing flaws that permit the sensing element (proof mass) to oscillate about an axis that is not orthogonal to the output axis. This creates an oscillation about the output axis that has a component of the sensing element's vibration acceleration. This output axis oscillation, which is in phase with the driven acceleration of the sensing element, is called quadrature torque since it is ninety degrees out of phase with the angular rate induced acceleration. In order to eliminate this output axis oscillation, the present invention generates sinusoidal forces on the dither mass by applying dc voltages on the dither mass pickoff electrodes. These forces create a counter dither motion about the output axis that cancels the output axis oscillation generated by the non-orthogonal dither axis.

Abstract: In an implementation in rate gyro mode, the method comprises the steps of exciting the vibrating member by means of a combination of control signals comprising an amplitude control signal at the resonant frequency of the vibrating member or at a frequency twice the resonant frequency, a precession control signal at a frequency twice the resonant frequency, and a quadrature control signal at DC, at the resonant frequency, or at a frequency twice the resonant frequency. In free gyro mode, the method includes the steps of applying a combination of signals to common electrodes 5 and of applying said combination in alternation to main electrodes 5.1 and 5.2 and to secondary electrodes 7.1 and 7.2 interleaved between the main electrodes.

Abstract: A tuning-fork type vibration gyro enables to suppress pyroelectric noise caused by temperature change and to obtain sensor output having high signal-to-noise ratio. The tuning-fork type vibration gyro includes a tuning-fork type vibration body having two arms mutually disposed in parallel and a base for commonly supporting one end of the each arm, wherein a longitudinal direction of the two arms is defined as a z-axis and a perpendicular direction thereto is defined as an x-axis; driving electrodes respectively formed on the two arms for generating vibration of the two arms in a direction parallel to the x-axis; detecting electrodes respectively formed on the two arms for detecting electromotive force generated when the tuning-fork type vibration body is rotated around the z-axis; and dummy electrodes formed on the two arms in respective areas different from the driving electrodes and the detecting electrodes.

Abstract: The present invention presents an angular velocity sensor having a self diagnosis function. An angular velocity sensor of the present invention includes a driving part for stably vibrating a driving part of a sensor element having a driver part and a detector part for detecting an angular velocity. The angular velocity sensor also includes a detection means for detecting the angular velocity of the sensor element. The angular velocity sensor obtains a self diagnosis signal for a malfunction by detecting a mechanical coupling signal obtained at the detection means.

Abstract: The present invention discloses methods of manufacturing mechanical resonator microgyroscopes using focused ion beam machining and the mechanical resonator gyroscopes produced therefrom. An exemplary method of tuning a mechanical resonator gyroscope, includes the steps of mounting a mechanical resonator gyroscope in a vacuum chamber with a controllable focused ion beam where the gyroscope includes exciting and sensing elements for measuring a resonant frequency of the gyroscope. The exciting and sensing elements are activated to measure the resonant frequency of the mechanical resonator gyroscope and the resonant frequency of the gyroscope is adjusted to a desired resonant frequency value by controlling the focused ion beam to remove material of the gyroscope.

Abstract: The resonant frequency of a device is determined by energizing the device with a short burst of energy to produce a decaying sinusoidal output, determining coefficients of a linear difference equation characterizing the decaying sinusoidal output by use of a least-mean-square fit, and determining the resonant frequency from the coefficients. The Q of the device can be determined from a decay parameter of the envelope of the decaying sinusoidal output and from the resonant frequency.