Abstract: A micromachined device has a body suspended over a substrate and movable in a plane relative to the substrate. The body has a perimeter portion, a first cross-piece portion extending from one part of the perimeter portion to another part of the perimeter portion to define at least first and second apertures, a first plurality of fingers extending along parallel axes from the perimeter portion into the first aperture, and a second plurality of fingers extending along parallel axes from the perimeter portion into the second aperture.

Abstract: A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Abstract: A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Abstract: A micromachined device has a first body suspended over a substrate in a plane parallel to the substrate and movable in the plane in a first direction relative to the substrate. A driver moves the first body in the first direction. A stop member, anchored to the substrate, limits motion of the body in the plane in a direction perpendicular to the first direction, and in a direction orthogonal to the plane and away from the substrate.

Abstract: A micromachined device has first and second sets of interdigitating fingers movable on a plane parallel to a substrate. A first group of conductive members is formed on the substrate and is at the same DC voltage as a first group of fingers. A second group of conductive members is formed on the substrate and is electrically coupled to the second group of fingers. The conductive members help to prevent one group of fingers from levitating with respect to others.

Abstract: A mechanical rate gyroscope including a micro-fabricated mechanical sensor. The mechanical sensor includes a first segmented drive system used to impart vibration to a mass and a transverse segmented drive system used to cancel a Coriolis force applied to the mass when the mechanical sensor undergoes rotation. The mechanical rate gyroscope further includes a force-feedback control mechanism used to provide at least one cycle of drive signals employed by the first drive system to the transverse drive system. The force-feedback control mechanism generates a feedback signal used to control the polarity of the drive signals provided to the transverse drive system. The feedback signal has a pulse repetition frequency proportional to the applied angular rate. The proportionality constant relating the applied angular rate to the pulse repetition frequency includes transduction coefficients that are less sensitive to the mechanical and electrical properties of the gyroscope.

Abstract: A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Abstract: A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Abstract: A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Abstract: A semiconductor magnetic field sensor including a substrate; a semiconductor moveable element suspended above the substrate, the moveable element being configured to have a current passed therethrough and to deflect perpendicularly with respect to an applied magnetic field; and at least one fixed semiconductor element arranged adjacent to the moveable element, the moveable element being deflected to or away from the fixed element in response to an applied magnetic field.

Abstract: A micromachined gyroscope has first and second coplanar bodies suspended over a substrate and movable in their plane relative to the substrate. The first body is dithered along a dither axis and is movable relative to the second body on the dither axis, but is rigidly connected for movement along an axis transverse to the dither axis. The second body is anchored so that it is substantially inhibited from moving along the dither axis, but can move with the first body along the transverse axis. The gyro has stop members and an anti-levitation system for preventing failure.

Abstract: A micromachined device has a plurality of rotationally dithered masses that are used to sense acceleration. To eliminate common modes, the masses are dithered in an equal and opposite manner. To help maintain this relationship between the movement of the masses, a coupling fork provides minimal resistance to anti-phase movement and substantial resistance to in-phase movement. Electrodes are used to detect changes in capacitance between the masses and the substrate resulting from rotation of the device about a radial axis of a mass. These electrodes are electrically connected to eliminate gradients that are caused by external forces and manufacturing differences. Four masses or more can be provided, arranged in a two-dimensional array, such as a square or hexagon with a coupling fork provided between each pair of masses, and with electrodes connected to eliminate gradients.

Abstract: A micromachined device has two suspended masses positioned near each other, each of the masses being dithered along a dither axis. Two couplings, each including an arcuate member and an anchored support beam, are provided between the masses to allow relative anti-phase movement and to resist relative in-phase movement. The coupling extends around a region intermediate the masses where a dither detection device is disposed.

Abstract: A micromachined device has a plurality of rotationally dithered masses that are used to sense acceleration. To eliminate common modes, the masses are dithered in an equal and opposite manner. To help maintain this relationship between the movement of the masses, a coupling fork provides minimal resistance to anti-phase movement and substantial resistance to in-phase movement. Electrodes are used to detect changes in capacitance between the masses and the substrate resulting from rotation of the device about a radial axis of a mass. These electrodes are electrically connected to eliminate gradients that are caused by external forces and manufacturing differences. Four masses or more can be provided, arranged in a two-dimensional array, such as a square or hexagon with a coupling fork provided between each pair of masses, and with electrodes connected to eliminate gradients.

Abstract: A ring laser gyroscope in which RF excitation is used to cause gas discharge as opposed to DC excitation which is used in conventional ring laser gyroscopes. External surfaces of the body of the ring laser gyroscope are metallized to form electrodes and an RF signal is capacitively coupled to gas reservoirs forming part of the lasing cavities.

Abstract: An integrated rate and acceleration sensor includes at least one accelerometer formed from a substantially planar silicon body. The at least one micro-silicon accelerometer (MSA) includes a first frame and a proof mass suspended from the first frame by first flexures. The at least one accelerometer has an associated sensitive axis and an associated rate axis that is orthogonally disposed to the sensitive axis. The integrated sensor further includes structure for dithering or vibrating the proof mass along a dither axis that is disposed perpendicularly to both the rate and the sensitive axes. The dithering structure includes at least first and second interdigitated electrodes. Finger portions of the electrodes are disposed for exerting an electrostatic force upon a portion of the planar body in response to an oscillatory drive signal.

Abstract: A miniature accelerometer is fabricated using integrated circuit manufacturing and silicon micromachining techniques to form a closed loop, force balance sensor utilizing a silicon proofmass formed from and connected to a layer of silicon by a split flexure etched therein. The sensor circuitry detects AC signals coupled from the proofmass to a pair of electrodes formed on glass surfaces anodically bonded to the silicon layer. A DC restorative force is applied to the electrodes in response to the detected AC signals to balance acceleration forces applied to the proofmass. The sensor design is highly symmetrical.

Abstract: Analog-to-digital converters are subject to errors including the known half least significant bit quantization error and also bit weighting errors due to lack of an ideal binary relationship between the transition points of all the bits. The known statistical average error reduction method in which a relatively small dither component is added to the analog input signal can only fractionally reduce overall error and has little effect on bit weighting errors. Herein the analog signal is added to a dither signal, for example a ramp signal, which varies through half the peak to peak digitization range of the converter so that irrespective of the input signal all output signal bits, other than the most significant bit, are "on" for one half of the sampling period. The result is that all the less significant bit errors are cancelled leaving only the easily compensated most significant bit error. A random component can be added to the dither signal to reduce the quantization error.

Abstract: Analog-to-digital converters are subject to errors including the known half least significant bit quantization error and also bit weighting errors due to lack of an ideal binary relationship between the transition points of all the bits. The known statistical average error reduction method in which a relatively small dither component is added to the analog input signal can only fractionally reduce overall error and has little effect on bit weighting errors. Herein the analog signal is added to a dither signal, for example a ramp signal, which varies through half the peak to peak digitization range of the converter so that irrespective of the input signal all output signal bits, other than the most significant bit, are "on" for one half of the sampling period. The result is that all the less significant bit errors are cancelled leaving only the easily compensated most significant bit error. A random component can be added to the dither signal to reduce the quantization error.

Abstract: In a multiple axis ring laser gyroscope in which one or more of the laser cavity corner mirrors is or are shared by different cavities and in which the laser beams in these different cavities operate at the same nominal frequency, scattering of the beam in one cavity into another cavity by the shared mirror(s) may produce disadvantageous lock-in effects. To at least lessen this possibility, the frequencies of the beams in the gyroscope disclosed herein are offset one from another, the offset being sufficient to affect lock in but not so great that the frequency of any beam is overly far from the lasing medium gain curve center. The frequency offsets may be produced by introducing offset bias signals into some channels of the gyroscope path length control servosystem.