Hrl Laboratories, LLC

Logan D Sorenson

Raviv Perahia

David T Chang

Hung P Nguyen

Lian X Huang

Deborah J Kirby

Richard J Joyce

Matthew J Pelliccione

Randall Lynn Kubena

Shuoqin Wang

Christopher Stephen Roper

Adour Vahe Kabakian

Matthew T Rakher

Jeremy Bregman

David L Walter

Joshua A Erbland

Adam Franklin Gross

John J Vajo

Jason A Graetz

Amit Madanlal Patel

David W Shahan

Keerti S Kona

Danny M Kim

Russell Patrick Mott

Patrick J Webb

Sean M Meenehan

Geoffrey P McKnight

Christopher Paul Henry

Tobias A Schaedler

Guillermo A Herrera

Christopher Burton Churchill

Phuong Bui

Kayleigh A Porter

Chia-Ming “Gavin” Chang

Jonathan Lake

Hung Nguyen

L X Coco Huang

Makena S White

Raviv Parahia

Chia-Ming "Gavin" Chang

A CVG having an axisymmetric resonator with first and second degenerate vibratory modes, having respectively first and second mode resonance frequencies (ω1, ω2) wherein said first and second mode resonance frequencies differ by a frequency difference (Δω); a plurality of electrodes arranged at a distance around a periphery of the resonator; said plurality of electrodes comprising at least one resonance frequency tuning electrode arranged for, upon application of a first bias voltage signal to said at least one resonance frequency tuning electrode, acting on the frequency difference (Δω) by changing at least one of the first and second mode resonance frequencies; and a resonance frequency loop circuit arranged to generate said first bias voltage signal and regulate a value of said first bias voltage signal to maintain said frequency difference (Δω) at a predetermined minimal value.

Real-time adaptive tuning of gyroscopes via quadrature dithering

A sensor cluster is disclosed comprising a first plurality of side surfaces of a first N-hedron structure, and a second plurality of side surfaces of a second N-hedron structure. A first plurality of a first type of sensor are mounted on the first plurality of side surfaces, and a second plurality of a second type of sensor are mounted on the second plurality of side surfaces. N is greater than three and the first plurality of side surfaces are interleaved with the second plurality of side surfaces.

Double N-hedron sensor cluster

A corner bracket comprising a volume of matter having n pairs of parallel faces, where n is an integer larger than 2; each face of each pair of parallel faces comprising an opening; the openings in the faces of each pair of parallel faces being joined by a cylindrical recess having a longitudinal axis perpendicular to the faces joined by the cylindrical recess; the longitudinal axis of the cylindrical recesses being arranged such that the cylindrical recesses do not intersect each other. The number n can be 3 and the volume of matter can be a cube.

Modular inertial measurement unit and elements for making same

A CVG having a resonator with two degenerated modes each with a nodal direction and an antinodal direction, with drive electrodes arranged near the respective nodal directions of the resonator and sense electrodes arranged near the respective antinodal directions of the resonator.

Gyroscope sensors having nodal push-pull actuation and antinodal readout

A Coriolis vibratory gyroscope having a resonator with at least a first and a second n=2 vibratory modes of same resonance frequency in a resonator plane; first and second sensing circuits for generating first and second sense signals in response to a motion of the resonator along a major axis of the first and second vibratory modes; a first drive circuit for driving the resonator in the first vibratory mode with a first drive signal; a second drive circuit for simultaneously driving the resonator in the second vibratory mode with a second drive signal; wherein said first signal has a first frequency equal to a resonant frequency of said resonator in said first vibratory mode, and said second signal has the same frequency as the first signal, modulated in amplitude with a second frequency.

Frequency multiplexed operation of vibratory gyroscopes for continuous self-calibration

A CVG having first and second degenerate resonator modes with each a damping rate; drive circuits for causing the resonator to oscillate in the first and second modes in response to first and second drive signals; first and second sense circuits for generating first and second sense signals in response to the resonator oscillating in the first and second modes; a signal processing circuit having control loops for generating the first and second drive signals based on the first and second sense signals; and first and second damping feedback circuits for generating first and second damping feedback signals proportional to the first and second damping rates; an adding the damping feedback signals to the first and second drive signals.

Continuous online self-calibration for gyroscopes through modulation of damping axes

A method and apparatus for for sensing a change in an acceleration gradient &#x3b4;a(t) between two gravity fields a(t) and a(t) respectively sensed by the first and second proof masses, the first and second proof masses either being coupled only to a first resonator or being individually coupled to first and second resonators, the first resonator generating, in use, a signal at a frequency fwhich is applied said second resonator, the second resonator being driven, in use, into a non-linear state corresponding to a modal resonant frequency fwherein it generates a comb of frequencies each tooth of which is separated from each other by a frequency &#x394; which is frequency-wise proportional a frequency difference between fand fand also proportional to the change in said acceleration gradient &#x3b4;a(t), circuitry for selecting an ntooth in said comb of frequencies where the frequency of the ntooth is equal to f+n&#x394;, circuitry for detecting a change in the frequency of the ntooth and for generating a signal that is proportional to n times the change in an acceleration gradient &#x3b4;a(t).

Phononic comb enhanced MEMS gravity gradiometers

A resonator includes an anchor, an outer stiffener ring on an outer perimeter of the resonator, and a plurality of curved springs between the anchor and the outer stiffener ring.

High quality factor mems silicon flower-of-life vibratory gyroscope

An angular rate sensor. The sensor includes a Coriolis vibratory gyroscope (CVG) resonator, configured to oscillate in a first normal mode and in a second normal mode; a frequency reference configured to generate a reference signal; and a first phase control circuit. The first phase control circuit is configured to: measure a first phase difference between: a first phase target, and the difference between: a phase of an oscillation of the first normal mode and a phase of the reference signal. The first phase control circuit is further configured to apply a first phase correction signal to the CVG resonator, to reduce the first phase difference. A second phase control circuit is similarly configured to apply a second phase correction signal to the CVG resonator, to reduce a corresponding, second phase difference.

High stability angular sensor

A resonator has a resonator body and a frame at least partially surrounding the resonator body, the resonator body being coupled to the frame by at least one tether. The resonator body, frame and at least one tether comprise silicon carbide. A plurality of interdigitated electrodes are disposed on the silicon carbide resonator body. The resonator body preferably comprises 6H silicon carbide and preferably has a crystalline c-axis oriented generally parallel to a thickness direction of the resonator body.

Piezoelectric single crystal silicon carbide microelectromechanical resonators

A self-calibration method for an accelerometer having a proof mass separated by a gap from a drive electrode and a sense electrode includes initializing the accelerometer to resonate, applying a first bias voltage to the sense electrode and a second bias voltage to the drive electrode to obtain a first scale factor, measuring a first acceleration over a first time interval, swapping the first bias voltage on the sense electrode with the second bias voltage previously on the drive electrode and the second bias voltage on the drive electrode with the first bias voltage previously on the sense electrode so that a bias voltage on the sense electrode is set to the second bias voltage and a bias voltage on the drive electrode is set to the second bias voltage to obtain a second scale factor, measuring a second acceleration over a second time interval, and calculating a true acceleration.

Continuous online self-calibrating resonant FM microelectromechanical systems (MEMS) accelerometer

A method of making a SiC resonator includes forming a layer of an oxide material on a relatively thick wafer of SiC; bonding the layer of oxide material on the relatively thick wafer of SiC to a handle wafer having at least an oxide exterior surface, the resulting bond being substantially free of voids; planarizing the relatively thick wafer of SiC to a desired thickness; forming top and bottom electrodes on the wafer of SiC wafer to define a SiC wafer resonator portion; and forming a trench around the top and bottom electrodes, the tench completely penetrating the planarized wafer of SiC around a majority of a distance surrounding said top and bottom electrodes, except for one or more tether regions of the planarized wafer of SiC which remain physically coupled a remaining portion the SiC wafer resonator portion which defines a frame formed of the planarized wafer of SiC surrounding the SiC wafer resonator portion.

Method of fabricating a SiC resonator

A stress isolating interposer includes: an outer pad; an inner pad configured to accommodate a positional sensor is mounted; and a stress isolating structure coupling the outer pad and the inner pad to each other. The outer pad, the stress isolating structure, and the inner pad are a monolithic structure.

Stress isolating interposer and sensor package and method of manufacturing the same

An instrument package for use during the drilling a wellbore. The instrument package includes a plurality of instruments such as accelerometers, gyroscopes, and magnetometers; a computer is configured to determine the current position of the plurality of instruments from a set of measurements produced by the plurality of instruments; and wherein the plurality of instruments are mechanically isolated from a drill head assembly by one or more multi-degree of freedom vibration isolators. The computer preferably has at least two modes different analytical modes of analyzing the set of measurements produced by the plurality of instruments, including a continuous mode and a survey mode, the continuous mode being operational during times that active drilling is occurring and the survey mode being operational during times that the active drilling is not occurring.

Continuous trajectory calculation for directional drilling

A resonant accelerometer includes a proof mass, one or more springs connecting the proof mass to an anchor, and one or more capacitive transduction gaps providing a void or space between the movable proof mass and a corresponding fixed electrode, wherein the static displacement of the proof mass in response to acceleration applied to the anchor modifies the electrostatic stiffness imparted by one or more of the capacitive transduction gaps on the proof mass, resulting in a corresponding change in the resonance frequency of the resonant accelerometer.

Growing community of inventors

Thousand Oaks, CA, United States of America

Logan D Sorenson