Abstract: A digital angular rate sensor system based on frequency modulation (FM) of the rotation rate. The new approach relies on tracking of the resonant frequencies of two high-Q mechanical modes of vibration in a MEMS vibratory gyroscope to produce an inherently digital measurement of the input angular rate. The disclosed system is enabled by a combination of a MEMS vibratory high-Q gyroscope and a new signal processing scheme which takes advantage of a previously ignored gyroscope dynamics effect. The FM nature of the system eliminates noise versus bandwidth and resolution versus dynamic range tradeoffs of conventional vibratory rate gyroscopes. The FM approach allows achieving superior signal-to-noise-ratio through the use of ultra-high Q (1 million) mechanical structure without limiting the measurement bandwidth. Stability of 1e-9 can be achieved in the FM system, providing a 1000 times improvement over the state-of-the-art conventional AM gyroscopes with capacitive pick-off.

Abstract: A z-axis gyroscope design is presented with a 2-degree of freedom (DOF) sense mode allowing interchangeable operation in either precision (mode-matched) or robust (wide-bandwidth) modes. This is accomplished using a complete 2-DOF coupled system which allows for the specification of the sense mode resonant frequencies and coupling independent of frequency. By decoupling the frame connecting the sense system to a central anchor, x-y symmetry is preserved while enabling a fully coupled 2-DOF sense mode providing control over both the bandwidth and the amount of coupling independent of operational frequency. The robust mode corresponds to operation between the 2-DOF sense mode resonant frequencies providing a response gain and bandwidth controlled by frequency spacing. Precision mode of operation, however, relies on mode-matching the drive to the second, anti-phase sense mode resonant frequency which can be designed to provide a gain advantage over a similar 1-DOF system.

Abstract: A multi-axis microelectromechanical-systems (MEMS) inertial measurement unit (IMU) is fabricated in a vacuum sealed single packaged device. An FM vibratory gyroscope and an FM resonant accelerometer both for generating FM output signals is fabricated in the silicon chip using MEMS. A signal processor is coupled to the an FM vibratory gyroscope and to the FM resonant accelerometer for receiving the FM gyroscopic output signals and the FM accelerometer output signals. The signal processor generates simultaneous and decoupled measurement of input acceleration, in put rotation rate, and temperature and/or temperature distribution within the IMU, self-calibration of the biases and scale factors of the IMU and its support electronics against temperature variations and other common mode errors, and reduction of the cross axis sensitivity by reducing acceleration errors in the gyroscope and rotation errors in the accelerometer.

Abstract: The current invention is a novel gyroscope design, which yields devices robust to fabrication and environmental variations, allows flexible selection of operational parameters, and provides increased bandwidth with minimized sacrifice in gain regardless of the selected frequency of operation. The gyroscope has a single degree-of-freedom (DOF) drive-mode and a 2-DOF sense-mode. The drive-mode operational frequency and the sense-mode bandwidth can be selected arbitrarily in the proposed design, relaxing the tradeoff between the gain, die size, and detection capacitance. The symmetry of the structure ensures the optimal location of the drive-mode resonance relative to the sense-mode operational region, even in presence of fabrication imperfections.

Abstract: The current invention is a novel gyroscope design, which yields devices robust to fabrication and environmental variations, allows flexible selection of operational parameters, and provides increased bandwidth with minimized sacrifice in gain regardless of the selected frequency of operation. The gyroscope has a single degree-of-freedom (DOF) drive-mode and a 2-DOF sense-mode. The drive-mode operational frequency and the sense-mode bandwidth can be selected arbitrarily in the proposed design, relaxing the tradeoff between the gain, die size, and detection capacitance. The symmetry of the structure ensures the optimal location of the drive-mode resonance relative to the sense-mode operational region, even in presence of fabrication imperfections.

Abstract: A high temperature micro-glassblowing process and a novel inverted-wineglass architecture that provides self-aligned stem structures. The fabrication process involves the etching of a fused quartz substrate wafer. A TSG or fused quartz device layer is then bonded onto the fused quartz substrate, creating a trapped air pocket or cavity between the substrate and the TSG device layer. The substrate and TSG device layer 14 are then heated at an extremely high temperature of approximately 1700° C., forming an inverted wineglass structure. Finally, the glassblown structure is cut or etched from the substrate to create a three dimensional wineglass resonator micro-device. The inverted wineglass structure may be used as a high performance resonator for use as a key element in precision clock resonators, dynamic MEMS sensors, and MEMS inertial sensors.

Abstract: A vibratory sensor is fabricated as a three-dimensional batch-micromachined shell adapted to vibrate and support elastic wave propagation and wave precession in the shell or membrane and at least one driving electrode and preferably a plurality of driving electrodes directly or indirectly coupled to the shell to excite and sustain the elastic waves in the shell. The pattern of elastic waves is determined by the configuration of the driving electrode(s). At least one sensing electrode and preferably a plurality of sensing electrodes are provided to detect the precession of the elastic wave pattern in the shell. The rotation of the shell induces precession of the elastic wave pattern in the shell which is usable to measure the rotation angle or rate of the vibratory sensor.

Abstract: A z-axis gyroscope design is presented with a 2-degree of freedom (DOF) sense mode allowing interchangeable operation in either precision (mode-matched) or robust (wide-bandwidth) modes. This is accomplished using a complete 2-DOF coupled system which allows for the specification of the sense mode resonant frequencies and coupling independent of frequency. By decoupling the frame connecting the sense system to a central anchor, x-y symmetry is preserved while enabling a fully coupled 2-DOF sense mode providing control over both the bandwidth and the amount of coupling independent of operational frequency. The robust mode corresponds to operation between the 2-DOF sense mode resonant frequencies providing a response gain and bandwidth controlled by frequency spacing. Precision mode of operation, however, relies on mode-matching the drive to the second, anti-phase sense mode resonant frequency which can be designed to provide a gain advantage over a similar 1-DOF system.

Abstract: A z-axis gyroscope design is presented with a 2-degree of freedom (DOF) sense mode allowing interchangeable operation in either precision (mode-matched) or robust (wide-bandwidth) modes. This is accomplished using a complete 2-DOF coupled system which allows for the specification of the sense mode resonant frequencies and coupling independent of frequency. By decoupling the frame connecting the sense system to a central anchor, x-y symmetry is preserved while enabling a fully coupled 2-DOF sense mode providing control over both the bandwidth and the amount of coupling independent of operational frequency. The robust mode corresponds to operation between the 2-DOF sense mode resonant frequencies providing a response gain and bandwidth controlled by frequency spacing. Precision mode of operation, however, relies on mode-matching the drive to the second, anti-phase sense mode resonant frequency which can be designed to provide a gain advantage over a similar 1-DOF system.

Abstract: A z-axis gyroscope design is presented with a 2-degree of freedom (DOF) sense mode allowing interchangeable operation in either precision (mode-matched) or robust (wide-bandwidth) modes. This is accomplished using a complete 2-DOF coupled system which allows for the specification of the sense mode resonant frequencies and coupling independent of frequency. By decoupling the frame connecting the sense system to a central anchor, x-y symmetry is preserved while enabling a fully coupled 2-DOF sense mode providing control over both the bandwidth and the amount of coupling independent of operational frequency. The robust mode corresponds to operation between the 2-DOF sense mode resonant frequencies providing a response gain and bandwidth controlled by frequency spacing. Precision mode of operation, however, relies on mode-matching the drive to the second, anti-phase sense mode resonant frequency which can be designed to provide a gain advantage over a similar 1-DOF system.

Abstract: The current invention is a novel gyroscope design, which yields devices robust to fabrication and environmental variations, allows flexible selection of operational parameters, and provides increased bandwidth with minimized sacrifice in gain regardless of the selected frequency of operation. The gyroscope has a single degree-of-freedom (DOF) drive-mode and a 2-DOF sense-mode. The drive-mode operational frequency and the sense-mode bandwidth can be selected arbitrarily in the proposed design, relaxing the tradeoff between the gain, die size, and detection capacitance. The symmetry of the structure ensures the optimal location of the drive-mode resonance relative to the sense-mode operational region, even in presence of fabrication imperfections.

Abstract: A digital angular rate sensor system based on frequency modulation (FM) of the rotation rate. The new approach relies on tracking of the resonant frequencies of two high-Q mechanical modes of vibration in a MEMS vibratory gyroscope to produce an inherently digital measurement of the input angular rate. The disclosed system is enabled by a combination of a MEMS vibratory high-Q gyroscope and a new signal processing scheme which takes advantage of a previously ignored gyroscope dynamics effect. The FM nature of the system eliminates noise versus bandwidth and resolution versus dynamic range tradeoffs of conventional vibratory rate gyroscopes. The FM approach allows achieving superior signal-to-noise-ratio through the use of ultra-high Q (1 million) mechanical structure without limiting the measurement bandwidth. Stability of 1e-9 can be achieved in the FM system, providing a 1000 times improvement over the state-of-the-art conventional AM gyroscopes with capacitive pick-off.

Abstract: The current invention is a novel gyroscope design, which yields devices robust to fabrication and environmental variations, allows flexible selection of operational parameters, and provides increased bandwidth with minimized sacrifice in gain regardless of the selected frequency of operation. The gyroscope has a single degree-of-freedom (DOF) drive-mode and a 2-DOF sense-mode. The drive-mode operational frequency and the sense-mode bandwidth can be selected arbitrarily in the proposed design, relaxing the tradeoff between the gain, die size, and detection capacitance. The symmetry of the structure ensures the optimal location of the drive-mode resonance relative to the sense-mode operational region, even in presence of fabrication imperfections.

Abstract: An apparatus is fabricated with a plurality of semiconductor-device substrates and/or MEMS substrates with micromachined sensors, circuits, transducers, and/or MEMS devices fabricated on the plurality of substrates. A plurality of flexible hinges couple the plurality of substrates into a substantially flat two dimensional foldable assembly. Electrical interconnects coupled to the sensors, circuits, transducers, and/or MEMS devices extend other ones of the plurality of substrates. The foldable assembly of substrates is assembled or folded into a three dimensional polyhedral structure with the plurality of substrates configured in three dimensions to form defined relative orientations in space with respect to each other. The invention includes a wafer scale method of fabricating the apparatus.

Abstract: A vibratory rate z-axis gyroscope is characterized by drive-mode and sense-mode quality factors and rate sensitivity and is fabricated with at least two decoupled vibratory tines, a levered drive-mode mechanism coupled between the tines to structurally force anti-phase drive-mode motion of the tines at a predetermined drive frequency, to eliminate spurious frequency modes of the anti-phase drive-mode motion of the tines lower than the predetermined drive frequency and to provide synchronization of drive- and sense-mode motion of the tines, and a sense-mode mechanism coupled between the tines arranged and configured to provide a linearly coupled, dynamically balanced anti-phase sense-mode motion of the tines to minimize substrate energy dissipation and to enhance the sense-mode quality factor and rate sensitivity.

Abstract: An apparatus is fabricated with a plurality of semiconductor-device substrates and/or MEMS substrates with micromachined sensors, circuits, transducers, and/or MEMS devices fabricated on the plurality of substrates. A plurality of flexible hinges couple the plurality of substrates into a substantially flat two dimensional foldable assembly. Electrical interconnects coupled to the sensors, circuits, transducers, and/or MEMS devices extend other ones of the plurality of substrates. The foldable assembly of substrates is assembled or folded into a three dimensional polyhedral structure with the plurality of substrates configured in three dimensions to form defined relative orientations in space with respect to each other. The invention includes a wafer scale method of fabricating the apparatus.

Abstract: The illustrated embodiment of the invention includes a capacitive detection method in a MEMS resonator comprising the steps of: vibrating a resonator with a drive signal; sensing vibration of the resonator by detecting a plurality of sidebands of an electromechanical amplitude modulation signal in a capacitive detector; and extracting amplitude of motion from a ratio of two simultaneously sensed sidebands of different order.

Abstract: A vibratory sensor is fabricated as a three-dimensional batch-micromachined shell adapted to vibrate and support elastic wave propagation and wave precession in the shell or membrane and at least one driving electrode and preferably a plurality of driving electrodes directly or indirectly coupled to the shell to excite and sustain the elastic waves in the shell. The pattern of elastic waves is determined by the configuration of the driving electrode(s). At least one sensing electrode and preferably a plurality of sensing electrodes are provided to detect the precession of the elastic wave pattern in the shell. The rotation of the shell induces precession of the elastic wave pattern in the shell which is usable to measure the rotation angle or rate of the vibratory sensor.

Abstract: A z-axis gyroscope design is presented with a 2-degree of freedom (DOF) sense mode allowing interchangeable operation in either precision (mode-matched) or robust (wide-bandwidth) modes. This is accomplished using a complete 2-DOF coupled system which allows for the specification of the sense mode resonant frequencies and coupling independent of frequency. By decoupling the frame connecting the sense system to a central anchor, x-y symmetry is preserved while enabling a fully coupled 2-DOF sense mode providing control over both the bandwidth and the amount of coupling independent of operational frequency. The robust mode corresponds to operation between the 2-DOF sense mode resonant frequencies providing a response gain and bandwidth controlled by frequency spacing. Precision mode of operation, however, relies on mode-matching the drive to the second, anti-phase sense mode resonant frequency which can be designed to provide a gain advantage over a similar 1-DOF system.

Abstract: The current invention is a novel gyroscope design, which yields devices robust to fabrication and environmental variations, allows flexible selection of operational parameters, and provides increased bandwidth minimized sacrifice in gain regardless of the selected frequency of operation. The gyroscope has a single degree-of-freedom (DOF) drive-mode and a 2-DOF sense-mode. The drive-mode operational frequency and the sense-mode bandwidth can be selected arbitrarily in the proposed design, relaxing the tradeoff between the gain, die size, and detection capacitance. The symmetry of the structure ensures the optimal location of the drive-mode resonance relative to the sense-mode operational region, even in presence of fabrication imperfections.