摘要:
Inertial sensors with reduced sensitivity to quadrature errors and micromachining inaccuracies include a gyroscope incorporating two specially-configured single-axis gyroscopes for sensing rotations about two orthogonal axes (the axes of sensitivity) in the device plane, where each single-axis gyroscope includes a resonator having two rotationally-dithered shuttles interconnected by a fork and each shuttle is configured to tilt out-of-plane along a tilt axis perpendicular to the axis of sensitivity and includes corresponding Coriolis sensing electrodes positioned along an axis perpendicular to the tilt axis (i.e., parallel to the axis of sensitivity). The two single-axis gyroscopes may be interconnected, e.g., by one or more in-phase or anti-phase couplings interconnecting the forks and/or the shuttles.
摘要:
A sensor element is capped by bonding or otherwise forming a cap on a sensor element. The sensor may be hermetically sealed by using a hermetic cap and hermetic bonding material or by applying a hermetic coating. The sensor may be filled with a gas at an elevated pressure. The sensor may alternatively or additionally be filled with a special gas, such as a gas having a density-to-viscosity ratio above approximately 0.2.
摘要:
An inertial sensor includes a cross-quad configuration of four interconnected sensor elements. Each sensor element has a frame and a resonator suspended within the frame. The sensor elements are arranged so that the frames of adjacent sensor elements are allowed to move in anti-phase to one another but are substantially prevented from moving in phase with one another. The sensor elements may be configured in a horizontally coupled arrangement, a vertically coupled arrangement, or a fully coupled arrangement. A pair of sensor elements may be vertically coupled.
摘要:
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.
摘要:
A mass includes a first set of drive fingers interdigitated with a first array of fixed drive fingers and a second set of drive fingers interdigitated with a second array of fixed drive fingers. Each array of fixed drive fingers is affixed to a substrate using a plurality of anchors. The anchors for the first and second arrays of fixed drive fingers are arranged to be co-linear in a lateral direction relative to the motion of the mass.
摘要:
Resonator structures include a plurality of resonator masses interconnected by a plurality of levers so as to resonate in anti-phase with one another. The levers include a plurality of lever fingers interdigitated with corresponding fixed fingers affixed to an underlying substrate for at least one of driving movement of the levers and sensing movement of the levers relative to the fixed fingers.
摘要:
A micromachined gyroscope makes use of Coriolis acceleration to detect and measure rotation rate about a plane normal to the surface of a substrate. Specifically, various resonating structures are suspended within a frame. The resonating structures include phase and anti-phase masses that are mechanically coupled in order to produce a single resonance frequency for the entire resonating system. Rotation of the micromachined gyroscope about the plane produces a rotational force on the frame. The frame is suspended in such a way that its motion is severely restricted in all but the rotational direction. Sensors on all sides of the frame detect the rotational deflection of the frame for measuring the change in direction.
摘要:
Quadrature suppression is provided by placing a resonator mass adjacent to a quadrature suppression electrode. The resonator mass is capable of moving substantially parallel to the quadrature suppression electrode and includes a notch formed adjacent to a portion of the quadrature suppression electrode such that a length of resonator mass that is directly adjacent to the quadrature suppression electrode varies as the resonator mass moves relative to the quadrature suppression electrode. The quadrature suppression electrode is capable of producing a lateral force on the resonator mass that varies based on the length of resonator mass that is directly adjacent to the quadrature suppression electrode. Such quadrature suppression can be used in sensors having one or more resonator masses.
摘要:
A micro-machined multi-sensor that provides 2-axes of acceleration sensing and 1-axis of angular rate sensing. The multi-sensor includes a rigid accelerometer frame, a first proof mass, and a second proof mass. The substrate has two associated acceleration axes in the plane of the substrate, and one associated rotation axis perpendicular to the acceleration axes. The proof masses have a common vibration axis, which is perpendicular to the rotation axis. The multi-sensor further includes a drive electrode structure for causing the proof masses to vibrate in antiphase, a first pair of acceleration sense electrode structures disposed along one of the acceleration axes, and a second pair of acceleration sense electrode structures disposed along the other acceleration axis. The multi-sensor adds the sense signals provided by the respective sense electrode pairs to extract information pertaining to acceleration sensing along the acceleration axes, and adds the differences of the sense signals provided by the respective sense electrode pairs to extract information pertaining to angular rate sensing relative to the rotation axis.
摘要:
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.