Ring laser gyroscope

About: Ring laser gyroscope is a research topic. Over the lifetime, 2070 publications have been published within this topic receiving 18609 citations. The topic is also known as: Sagnac interferometer.

Systematic Calibration Method for the Laser Gyro Strapdown Inertial Navigation System

Abstract: In this paper, based on the inertial navigation equation, a novel systematic calibration model for the laser gyro strapdown inertial navigation system is proposed. The observability of the error parameters is analyzed. Then a calibration algorithm, which can identify twenty four error parameters of the inertial navigation unit is studied.

Mirror design for piezo-driven mechanical devices: Modeling and simulations

Abstract: The principal operation of a ring laser gyroscope depends on the phase difference for the counter-propagating waves within a closed path. The reflection mirrors mounted on the resonator block form the traveling waves. Thus, the dimension accuracy of resonator block influences the traveling path of beam. In order to maintain the stable optical beam path in the ring resonator, the piezo-driven moveable mirror is adopted for the path length control under the thermal expansion or mechanical strain of resonator block. This paper presents the mathematical description of the elastic behavior of piezo-driven mirror. This description can be applied for the concept design of piezo-driven mirror. For the beam path control due to a piezo-driven mirror, this paper presents a theory of deflection of piezo-driven mirror as a function of the geometries and material properties of mirror components. In comparison with the simulation of finite element model, the theoretical result has the feasible error tolerance. If the effective geometries on the base of deformation can be taken into account, the more precise result can be calculated. But through the comparison, the presented theoretical approaches are known to be available.

Laser gyro cavity length control system and control method thereof

Abstract: The invention belongs to a laser gyro technology, and relates to a laser gyro cavity length control method. The method uses a beat frequency signal output after light combination of a laser gyro to realize cavity length control, and concretely comprises the following steps: carrying out amplitude demodulation on the beat frequency signal, calculating a difference between the above obtained result and a reference voltage, amplifying the difference to obtain a cavity length control signal, and controlling through a three point comparison technology to make the signal stable at a maximum value (the top of a gain curve) in order to realize the stability of the cavity length. The cavity length control is realized by using the beat frequency signal output after light combination of the laser gyro only through one output mirror without a photoelectric converter for receiving clockwise and anticlockwise light of the gyro, a light splitting prism or a preamplifier, so the cost is greatly reduced, the alignment process of the gyro is simplified, and the cavity loss is greatly reduced, thereby the improvement of the precision of the gyro is facilitated.

Method of constructing a moment insensitive pathlength control mirror assembly for a ring laser gyroscope

Abstract: In a precision ring laser gyroscope, to eliminate the effect of an unwanted and unintentional moment generated as a result of a force being applied onto a pathlength controller, a pathlength control assembly is constructed to have optimal hub and diaphragm portions such that the mirror element mounted thereto does not tilt in response to the unintentional moment.

Balanced dual servo VCO passive ring laser gyroscope

Abstract: A passive ring resonator gyroscope comprising a single piece body having an integral first and second resonator cavity. The first resonator cavity contains a single frequency laser means to provide a sharply tuned single frequency light source to the second resonator cavity. The single frequency light source is sharply tuned and is split to form first and second sources. The second resonator cavity is a passive high Q cavity having a closed second optical path. The two light sources are fed to the second resonator and propagate as CW and CCW beams within the second resonator. A first servo channel tunes the frequency of the CW beam to a resonance peak. A second servo channel tunes the CCW beam to its resonance peak. By converting both servo error outputs into frequency, the relative frequency difference between the CW and CCW beams are recorded as the frequency shift in response to the body rate rotation about the sensitive axis. The first and second control signals are algebraicly added to provide a passive cavity path length difference servo signal which is integrated. A SECOND ADDER adds the integrated passive cavity difference signal to the reference signal (Fm) to provide the passive cavity path length servo signal to a passive cavity path length adjusting means for constantly adjusting the passive cavity path length servo signal to keep the passive cavity at peak resonance at a frequency substantially mid-range between the propagating (FCW) and the counterpropagating beams (FCCW).