Litef Gmbh

Northrop Grumman Litef Gmbh

Guenter Spahlinger

Sven Voigt

Olaf Deppe-Reibold

Wolfram Geiger

Alfons Newzella

Julian Bartholomeyczik

Peter Leinfelder

Uwe Breng

Martin Hafen

Steffen Zimmermann

The control system for a fiber-optic gyroscope comprises a phase modulator for modulating a phase of a light signal and a control unit for producing a control signal, by the magnitude of which the phase is modulated and which is fed to the phase modulator. Moreover, the control system comprises an integration unit for determining an integral value of an integral over an input signal. Here, the control signal assumes a first value or a second value depending on the integral value.

Phase modulator for fibre-optic gyroscope, fibre-optic gyroscope and method for operating a phase modulator

The invention relates to a device () for controlling a sensor (), comprising a converter unit () for converting an input signal () into a control signal () for controlling said sensor (), and a comparison unit () for determining a differential signal () that indicates the difference between said input signal () and control signal (). The device also comprises a feedback unit () for regulating the input signal () using said differential signal (). A differential signal () transfer function has a zero point at a sensor () operating frequency which does not equal zero.

Device and method for processing of residual values when controlling a sensor

The invention relates to a control system () for a fiber optic gryoscope, comprising a phase modulator () for modulating a phase of a light signal () and a control unit () for producing a control signal (), by the value of which the phase is modulated and which is fed to the phase modulator (). The control signal changes statistically and does not have an average value.

Phase modulator for fiber-optic gyroscopes controlled in a zero-mean manner and a fiber-optic gyroscope

In a method for producing a component, a first layer composite is first produced, comprising a structured layer and a trench filled with an insulating material. The structured layer is electrically conductive at least in a first region. The trench filled with an insulating material extends outwards from a first surface of the structured layer and is arranged in the first region of the structured layer. The first surface of the structured layer faces a first surface of the first layer composite. The method additionally has the step of producing a second layer composite, which has a first depression in a first surface of the second layer composite, and the step of connecting the first layer composite to the second layer composite. The first surface of the first layer composite adjoins the first surface of the second layer composite at least in some regions, said filled trench being arranged within the lateral position of the first depression. After the first layer composite has been connected to the second layer composite, the thickness of the first layer composite from a second surface of the first layer composite to the depth of the filled trench is reduced. The second surface of the first layer composite lies opposite the first surface of the first layer composite. The method further has the step of producing an active structure in the structured layer, said active structure comprising two second regions which are arranged in the first region of the structured layer and which are mechanically connected to each other in a rigid manner but are electrically insulated from each other by means of the filled trench.

Method for producing a component

A fiber-optic Sagnac interferometer in a rotation rate sensor comprises a multifunctional integrated optical chip (MIOC) with a MIOC transfer function. A digital filter is connected upstream to the multi-functional integrated optical chip, whose filter transfer function corresponds basically to the inverse MIOC transfer function such that the MIOC transfer function is compensated by the filter transfer function. Corresponding coefficients of the filter transfer function may be determined in a main control loop.

Suppression of lock-in effect due to a MIOC frequency response in a fiber-optic Sagnac interferometer

A microelectromechanical sensor and operating method therefor. The sensor has at least one movable electrode. An electrode arrangement is spaced apart from the movable electrode with a plurality of electrodes that can be driven separately and to which corresponding electrode signals can be applied that can be used to electrostatically set/change the application of force, the spring constant and the read-out factor of the movable electrode. An electrode signal generation unit is connected to the electrode arrangement and can be supplied with a force application signal, a spring constant signal and a read-out factor signal, which define the settings/changes to be brought about with regard to the application of force, spring constant and read-out factor of the movable electrode. The electrode signal generation unit generates each electrode signal in a manner dependent on the force application signal, the spring constant signal and the read-out factor signal and matches the electrode signals to one another so that the application of force, the spring constant and the read-out factor of the movable electrode can be set/changed to specific desired values independently of one another.

Microelectromechanical sensor and operating method for a microelectromechanical sensor

A rotation rate sensor comprises a substrate and two structures which move relative to the substrate on a design plane (x-y), with the two moving structures being coupled to form a coupled structure such that the coupled structure has a first oscillation mode with antiphase deflections of the moving structures in a first direction (x) on the design plane (x-y) as excitation mode. The coupled structure has a second oscillation mode as a detection mode which is excited by Coriolis accelerations when the first oscillation mode is excited and on rotation about a sensitive axis (z) of the rotation rate sensor. The sensitive axis is at right angles to the design plane (x-y), and the coupled structure is designed such that, subject to optimal preconditions, it does not have any oscillation mode which can be excited by linear accelerations of the rotation rate sensor in a direction parallel to the second axis.

Rotation rate sensor

A method and a switch arrangement for operating a micromechanical capacitive sensor having at least one and at most two fixed electrodes and one differential capacitor formed by a movable central electrode that can be deflected by an external force, wherein the deflection of the electrode is measured. A fraction of the force acting on the central electrode, corresponding to the electrostatic restorative force, is compensated. Under closed-loop operation, a selection signal is influenced by a regulator supplementing a restore crosstalk signal so that the created capacitive restorative force acts in a compensatory manner against deflection of the central electrode.

Operating method and circuit arrangement for a capacitive micromechanical sensor with analog reset

A digital phase modulator for a fiber-optic measurement device. A predetermined total number of electrodes of different lengths are arranged in parallel and on both sides of a light guidance path in or on an optical substrate. The electrodes are arranged in two or more triples along the light guidance path. In each case, two electrodes of successive length within a triple have the same length ratio with respect to one another. Such length ratio is chosen, in particular, to be &#x3bd;=1.618. The electrode lengths of this triple are chosen such that the smallest step widths of the output value range of the phase modulator can be formed by subtraction between the values of at least two larger electrodes. This allows the resolution of the phase modulator to be increased from 9 bits to 11 bits without change in chip size.

High-resolution digital phase modulator for a fiber-optic signal transmission or measurement device

An operating method for a Coriolis gyro. Digital read signals are produced that represent a measure of the instantaneous amplitudes/frequencies of the stimulation oscillation/read oscillation of the gyro resonator. Force signals are applied to the resonator. The force signals are controlled as a function of the digital read signals so that the stimulation oscillation/read oscillation assume specific amplitudes/frequencies. The force signals are produced from quantized output signals from a pulse modulator. The modulator is fed with digital stimulation/compensation signals derived from the digital read signals.

Operating method for a Coriolis gyro, and evaluation/control electronics which are suitable for this purpose

A pulse modulator has a subtraction stage that produces a control error signal from the difference between a complex input signal and a feedback signal. A signal conversion stage converts the control error signal to a control signal. The control signal is multiplied by a complex mixing signal at the frequency &#x3c9;in a first multiplication stage. At least one of the real and imaginary parts of the up-mixed control signal is then quantized by a quantization stage to produce a real pulsed signal. The pulsed signal is then employed to produce the feedback signal for the subtraction stage in a feedback unit. The pulse modulator according to the invention allows the range of reduced quantization noise to be shifted toward a desired operating frequency &#x3c9;.

Pulse modulator and pulse modulation method

A method for controlling/regulating a physical variable of a dynamic system to a specific desired value profile with use made of a pulse modulator that generates a sequence of discrete modulation signals that affect the control or regulation of the physical variable. The method involves repeated execution of: determining an exact value or an approximation for the deviation between the momentary desired value and the momentary actual value of the physical variable; determining the respective change in the deviation which would result from the maintenance of the momentary modulation signal or the switching over to the other modulation signals; and generating that modulation signal which results in the best approximation of the momentary desired value.

Method for controlling/regulating a physical quantity of a dynamic system, in particular a micromechanical sensor

A method and arrangement of electrodes for increasing the resolution of a digital phase modulator for a fiber-optic signal transmission or measuring device. A predetermined total number m of electrodes of different lengths are arranged parallel and on both sides with respect to a light guiding path in or on an optical substrate. The electrodes are divided into two groups. A first group n of electrodes represents a coarse modulator with binary and more significant weighted electrodes of length ratio b:b=2, the longest electrode of which corresponds to the sum of lengths of all the remaining electrodes of the overall modulator. A second, smaller group of nnon-binary and less significant weighted electrodes represents a fine modulator. The smallest output values are not formed by driving individual electrodes of the fine modulator, but rather by forming the difference, in each case, between two larger electrodes.

Digital phase modulator for a fiber-optic device

A method for determination of/compensation for the bias/random walk errors induced by the light source in fiber-optic Sagnac interferometers employing a modulation method for stochastically independent shifting of the operating point to the points of highest sensitivity. A reference beam is output from the light beam emitted from the light source of the interferometer and passed to the fiber coil to produce a proportional reference intensity signal. Such signal is demodulated with the demodulation pattern of the rotation rate control loop to demodulate the rotation rate intensity signal (proportional to rotation rate). The demodulated reference intensity signal measures the bias/random walk errors to be determined. Demodulation of the reference intensity signal is simultaneous with that of the rotation rate intensity signal so that components of the reference and rotation rate intensity signals (each resulting from light components simultaneously emitted from the light source) are identically demodulated.

Method for determination/compensation of bias errors/random walk errors induced by the light source in fiber-optic Sagnac interferometers

A method for regulating the operating frequency of a closed loop fiber optic gyroscope. The demodulated output signal of a detector, as actual signal, is applied to the input of a main controller and, via a gating filter, to a VCO that determines the system clock of the FOG. An additional modulation signal, as analog signal is fed to separate phase correction electrodes that are formed together with the electrodes of a digital phase modulator in an integrated optical chip.

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Stuttgart, Germany

Guenter Spahlinger