Litton Systems, Inc.

Northrop Grumman Systems Corporation

Northrop Grumman Guidance and Electronics Company, Inc.

Litef Gmbh

Northrup Grumman Corp.

Northrop Grumman Guidance and Electronic Company, Inc.

Northrop Grumman Guidance and Electronic Corporation, Inc.

Daniel A Tazartes

John G Mark

Charles H Volk

David I Tazartes

Tae W Hahn

Brian T Lottman

George A Pavlath

Stanley F Wyse

Amado Cordova

Peter Kyriacou

Juergen K Flamm

Agop Hygasov Cherbettchian

James R Huddle

Robert John Buchler

Charles A Lee

Steven M Kim

Kenneth Marino

Gregory A Zimmerman

Robert E Ebner

James G Welker

Daniel P Wiener

Dean E Lottman

Shaw-Wen Fann

Michael W Denice, Jr

Maureen Lipman, Legal Representative

Kenneth D Marino

David Barnett Hall

Eric Lee Goldner

Donald A Frederick

Anthony Robert Matthews

Ragini Saxena

Daniel Perrine McLane

John R Hall

Albert V Scappaticci

Bassam S Dimashkie

Victor F Strachan

Ray D Dykeman

Jerome S Lipman

John E Higbee

Shaw W Fann

Yumi Yoshida

Juergen K P Flamm

Howell J Tipton

Yury A Litmanovich

Rosario J Milelli

Larry R Moeller

Anthony Mathews

James G Marsden

William B Ware

G Kevin Liu

Jacque A Tazartes

Nibir K Datta

Neal J Dahlen

Jonathan A Lincoln

Brent Robert Bateman

Philip T Kent

Mauricio Ribes

Jerome S Di Lipman

Robert J Buchler

One example includes a FOG assembly including a spool that includes a flattened portion corresponding to a flange comprising an axial center corresponding to a sensitive axis about which an associated FOG system is configured to measure rotation. The FOG assembly also includes a magnetic shield arranged as a capped concentric cover about the sensitive axis and coupled to the spool and the flange to create a toroidal cavity between the magnetic shield and the flange. A fiber coil is disposed within the toroidal cavity and coupled to the flange. The fiber coil includes an optical fiber which is counter-wound in first and second orientations. The fiber coil has an axial dimension along the sensitive axis that is less than or equal to approximately 160% of a radial width corresponding to a difference between an outer radius and an inner radius of the fiber coil.

Fiber-optic gyroscope (FOG) assembly

One example includes a fiber-optic gyroscope (FOG) system that includes a fiber coil. The coil includes an optical fiber wound around a spool of a FOG. The optical fiber includes a first input and a second input. The system also includes an optical beam controller comprising an optical switch that provides a first optical beam to the first input and a second optical beam to the second input during a first switching state, and provides the first optical beam to the second input and the second optical beam to the first input during a second switching state. The system further includes a controller that mitigates bias error in determining rotation of the FOG based on comparing the first and second optical beams output from the FOG during the first and second switching states.

Calibration circuit to mitigate fiber-optic gyroscope (FOG) bias error

A control system includes a processor that operates one or more control loops that enable gyroscopic angular measurement for an inertial measurement unit (IMU). Each of the one or more control loops operates over a range of set points defined for each of the respective control loops. A dynamic loop adjuster receives environmental input data to determine environmental conditions for the IMU. The dynamic loop adjuster alters at least one of the set points for at least one of the one or more control loops operated by the processor based on the determined environmental conditions.

Adaptive inertial measurement system and method

A fiber optic gyroscope (FOG) is provided. The FOG comprises a depolarizer that receives light from a light source, a multifunction integrated optic chip (MIOC) and a sensing coil coupled to outputs of the MIOC. The FOG also includes a polarizer coupled between an output of the depolarizer and an input of the MIOC. The polarizer mitigates polarization non-reciprocity (PNR) bias error and enhances the polarization extinction ratio (PER) of the FOG.

Fiber optic gyroscope with front end polarizer

A system is provided for controlling the amplitude of a vibrating resonant sensor through a drive signal applied to the resonator. The system comprises a controller that provides the drive signal to a forcer coupled to the resonator to excite the resonator into vibration at its resonant frequency. The system further comprises a buffer having an input node that receives charge of a pickoff capacitor of the resonator that is a measure of the resonator vibration and a current reference waveform. The buffer provides an output that is a difference signal that represents an error of the resonator vibration that corresponds to a difference between the measured resonator vibration and the current reference waveform, wherein the controller adjusts the drive signal in order to null the difference signal.

Amplitude control for vibrating resonant sensors

An exemplary navigation system uses a master navigation component at a first location in a vehicle and a slave navigation component at a second location that is a variable displacement to the first location due to physical deformation of the vehicle. Static and dynamic location components provide static and dynamic information of the displacement between the first and second locations. An error estimator estimates errors in the navigational measurement data generated by the slave navigation component based on the navigational measurement data generated by the master navigation component and the displacement information provided by the static and dynamic location components. The master navigation component corrects the navigation measurement data of the slave navigation component based on the determined error and translates the corrected navigation measurement data of the slave navigation component into navigational measurement data in its coordinate system.

System for multiple navigation components

A gyroscope having photonic crystals for sensing rotation uses the Sagnac effect to determine angular motion. The gyroscope comprises a photonic crystal capable of guiding counter-propagating light beams in a closed path. A light source, coupling, and detection apparatus permits detection of phase changes between the counter-propagating beams, thereby permitting measurement of angular rotation. The photonic crystal comprises a periodic structure of pillars and voids which creates a photonic bandgap waveguide within which light waves in the proper wavelength range propagate with low loss.

Photonic crystal based sensor or modulator

Photonic crystal based rotation sensor

An automatic gain control system for a fiber optic gyroscope control loop includes an adjustable gain applied to the gyro output signal. A pilot signal is injected into the fiber optic gyroscope control loop. A compensation loop receives signals output from the control loop and also receives pilot signals. The compensation loop processes the pilot signal to produce a compensation signal that is combined with signals output from the control loop to provide a compensated fiber optic gyroscope output signal. An automatic gain control loop is connected between the compensation loop and the adjustable gain applied to the fiber optic gyroscope output signal. The automatic gain control loop includes a gain error demodulator that multiplies the compensated fiber optic gyroscope output signal and the compensation signal together to produce a gain error signal used to control the adjustable gain in order to stabilize the gain of the gyro control loop.

Automatic gain control for fiber optic gyroscope deterministic control loops

A fiber optic gyroscope signal process dither system permits application of a low amplitude dither signal for many sampling periods without increasing the noise in the sampled outputs due to residual dither signals. A dither loop and an accumulator are added to a closed loop fiber optic gyroscope rotation sensing system. The dither loop has a delay and a gain that are adjusted to match the gain and delay of the fiber gyro loop. A zero mean dither of amplitude sufficient to break up the deadband is injected into to gyro and the dither loop. The dither loop filters the dither signal in the same manner as the gyro loop to provide a signal that is input to a differencing circuit to remove the dither signal from the gyro output.

Fiber optic gyroscope deadband circumvention apparatus and method

An exemplary navigation system uses a master navigation component at a first location with a first sensor in a vehicle and a slave navigation component with a second sensor at a second location that is a variable displacement to the first location due to physical deformation of the vehicle. Static and dynamic location components provide static and dynamic information of the displacement between the first and second locations. A flexural model based on the deformation characteristics calculates the dynamic displacement. An error estimator estimates errors in the navigation measurement data of the slave navigation component based on the displacement information. The master navigational component corrects the navigation measurement data of the slave navigation component based on the determined error, translates the corrected navigation measurement data of the slave navigation component into navigation measurement data in its coordinate system, and combines the output of the second sensor based on the corrected navigation measurement data with the output of the first sensor into a combined result.

System for interferometric sensing

In an exemplary display system adapted to display an image to an observer using a display where at least one of the display and observer is subjected to physical vibration referred to as jitter, accelerometers are mounted to elements subject to jitter and associated with the observer. A processing system uses acceleration measurements from the accelerometers to calculate an x-axis and y-axis jitter correction factors based on a comparison of the acceleration measurements, and generates a video output in which the visual information is displaced along the x-axis and y-axis based on the x-axis and y-axis jitter correction factors so that an image corresponding to the video output shown on the display appears to the observer as not having jitter.

Stabilization of the effects of jitter on a displayed image

In an embodiment of a ring laser gyroscope, a hollow bandgap fiber is filled with a gas or material that will generate laser beams within the fiber upon being excited by an energy source. A detector coupled to the fiber detects a standing wave pattern within the fiber, wherein changes in the detected standing wave pattern indicates a corresponding change in the orientation of the fiber.

Ring laser gyroscope that does not require mirrors

A method for attitude alignment of a slave inertial measurement system connected to a rotationally mobile platform supported by a vehicle that is stationary relative to a reference navigation frame comprises the steps of mounting a master reference inertial measurement system on the rotationally mobile platform and determining a master reference system attitude using measurements of acceleration and angular rates of the master reference inertial measurement system relative to the reference navigation frame. A slave system attitude is determined using measurements of acceleration and angular rates of the slave inertial measurement system relative to a slave system navigation reference frame and comparing the slave system attitude to the master reference system attitude to determine an attitude difference. The attitude difference is processed to obtain a correction to the slave system attitude.

Attitude alignment of a slave inertial measurement system

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West Hills, CA, United States of America

Daniel A Tazartes