摘要:
Parametrically disciplined operation of a symmetric nearly degenerate mode vibratory gyroscope is disclosed. A parametrically-disciplined inertial wave gyroscope having a natural oscillation frequency in the neighborhood of a sub-harmonic of an external stable clock reference is produced by driving an electrostatic bias electrode at approximately twice this sub-harmonic frequency to achieve disciplined frequency and phase operation of the resonator. A nearly symmetric parametrically-disciplined inertial wave gyroscope that can oscillate in any transverse direction and has more than one bias electrostatic electrode that can be independently driven at twice its oscillation frequency at an amplitude and phase that disciplines its damping to zero in any vibration direction. In addition, operation of a parametrically-disciplined inertial wave gyroscope is taught in which the precession rate of the driven vibration pattern is digitally disciplined to a prescribed non-zero reference value.
摘要:
The present invention discloses a resonator gyroscope comprising a vibrationally isolated resonator including a proof mass, a counterbalancing plate having an extensive planar region, and one or more flexures interconnecting the proof mass and counterbalancing plate. A baseplate is affixed to the resonator by the one or more flexures and sense and drive electrodes are affixed to the baseplate proximate to the extensive planar region of the counterbalancing plate for exciting the resonator and sensing movement of the gyroscope. The isolated resonator transfers substantially no net momentum to the baseplate when the resonator is excited.
摘要:
A Multiple Internal Seal Ring (MISR) Micro-Electro-Mechanical System (MEMS) vacuum packaging method that hermetically seals MEMS devices using MISR. The method bonds a capping plate having metal seal rings to a base plate having metal seal rings by wafer bonding the capping plate wafer to the base plate wafer. Bulk electrodes may be used to provide conductive paths between the seal rings on the base plate and the capping plate. All seals are made using only metal-to-metal seal rings deposited on the polished surfaces of the base plate and capping plate wafers. However, multiple electrical feed-through metal traces are provided by fabricating via holes through the capping plate for electrical connection from the outside of the package through the via-holes to the inside of the package. Each metal seal ring serves the dual purposes of hermetic sealing and providing the electrical feed-through metal trace.
摘要:
The present invention discloses an inertial sensor having an integral resonator. A typical sensor comprises a planar mechanical resonator for sensing motion of the inertial sensor and a case for housing the resonator. The resonator and a wall of the case are defined through an etching process. A typical method of producing the resonator includes etching a baseplate, bonding a wafer to the etched baseplate, through etching the wafer to form a planar mechanical resonator and the wall of the case and bonding an end cap wafer to the wall to complete the case.
摘要:
The present invention discloses a gyroscope comprising an isolated resonator including a post proof mass and counterbalancing plate. One or more double beam flexures each interconnect the counterbalancing plate and the proof mass with a first and a second beam attached to the post proof mass and a third and a fourth beam attached to the counterbalancing plate. A baseplate is affixed to the resonator by the double beam flexures. The counterbalancing plate and the proof mass transfer substantially no net momentum to the baseplate when the resonator is excited.
摘要:
An inertial sensor includes a mesoscaled disc resonator comprised of micro-machined substantially thermally non-conductive wafer with low coefficient of thermal expansion for sensing substantially in-plane vibration, a rigid support coupled to the resonator at a central mounting point of the resonator, at least one excitation electrode within an interior of the resonator to excite internal in-plane vibration of the resonator, and at least one sensing electrode within the interior of the resonator for sensing the internal in-plane vibration of the resonator. The inertial sensor is fabricated by etching a baseplate, bonding the substantially thermally non-conductive wafer to the etched baseplate, through-etching the wafer using deep reactive ion etching to form the resonator, depositing a thin conductive film on the through-etched wafer. The substantially thermally non-conductive wafer may comprise a silicon dioxide glass wafer, which is a silica glass wafer or a borosilicate glass wafer, or a silicon-germanium wafer.
摘要:
The present invention discloses an inertial sensor comprising a planar mechanical resonator with embedded sensing and actuation for substantially in-plane vibration and having a central rigid support for the resonator. At least one excitation or torquer electrode is disposed within an interior of the resonator to excite in-plane vibration of the resonator and at least one sensing or pickoff electrode is disposed within the interior of the resonator for sensing the motion of the excited resonator. In one embodiment, the planar resonator includes a plurality of slots in an annular pattern; in another embodiment, the planar mechanical resonator comprises four masses; each embodiment having a simple degenerate pair of in-plane vibration modes.
摘要:
The present invention discloses a resonator gyroscope including an isolated resonator. One or more flexures support the isolated resonator and a baseplate is affixed to the resonator by the flexures. Drive and sense elements are affixed to the baseplate and used to excite the resonator and sense movement of the gyroscope. In addition, at least one secondary element (e.g., another electrode) is affixed to the baseplate and used for trimming isolation of the resonator. The resonator operates such that it transfers substantially no net momentum to the baseplate when the resonator is excited. Typically, the isolated resonator comprises a proof mass and a counterbalancing plate.
摘要:
A Multiple Internal Seal Ring (MISR) Micro-Electro-Mechanical System (MEMS) vacuum package that hermetically seals MEMS devices using MISR. The method bonds a capping plate having metal seal rings to a base plate having metal seal rings by wafer bonding the capping plate wafer to the base plate wafer. Bulk electrodes may be used to provide conductive paths between the seal rings on the base plate and the capping plate. All seals are made using only metal-to-metal seal rings deposited on the polished surfaces of the base plate and capping plate wafers. However, multiple electrical feed-through metal traces are provided by fabricating via holes through the capping plate for electrical connection from the outside of the package through the via-holes to the inside of the package. Each metal seal ring serves the dual purposes of hermetic sealing and providing the electrical feed-through metal trace.
摘要:
An inertial sensor includes a mesoscaled disc resonator comprised of micro-machined substantially thermally non-conductive wafer with low coefficient of thermal expansion for sensing substantially in-plane vibration, a rigid support coupled to the resonator at a central mounting point of the resonator, at least one excitation electrode within an interior of the resonator to excite internal in-plane vibration of the resonator, and at least one sensing electrode within the interior of the resonator for sensing the internal in-plane vibration of the resonator. The inertial sensor is fabricated by etching a baseplate, bonding the substantially thermally non-conductive wafer to the etched baseplate, through-etching the wafer using deep reactive ion etching to form the resonator, depositing a thin conductive film on the through-etched wafer. The substantially thermally non-conductive wafer may comprise a silicon dioxide glass wafer, which is a silica glass wafer or a borosilicate glass wafer, or a silicon-germanium wafer.