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.

Multiple-Point Temperature Gradient Algorithm for Ring Laser Gyroscope Bias Compensation.

Abstract: To further improve ring laser gyroscope (RLG) bias stability, a multiple-point temperature gradient algorithm is proposed for RLG bias compensation in this paper. Based on the multiple-point temperature measurement system, a complete thermo-image of the RLG block is developed. Combined with the multiple-point temperature gradients between different points of the RLG block, the particle swarm optimization algorithm is used to tune the support vector machine (SVM) parameters, and an optimized design for selecting the thermometer locations is also discussed. The experimental results validate the superiority of the introduced method and enhance the precision and generalizability in the RLG bias compensation model.

Laser gyroscope detector and path length control system

Abstract: A four frequency laser gyroscope system having parallel processing of path length control and detection signals. Two output signal beams each containing components of two of the four waves circulating in the laser cavity are shone upon separate detector diodes. The output signals from the diodes contain both high and low frequency components which are separated in a crossover circuit. The low frequency component is processed to control the optical path length while the high frequency component is processed to produce a digital signal representing the amount of rotation of the laser gyroscope cavity.

Providing an Inexpensive Gyro for the Navigation Mass Market

Abstract: The Micro-Optic Gyro is an all-solid-state, passive ring resonator, laser gyro. It uses a waveguide resonator fabricated in glass by ion-exchange, a GaAlAs diode laser, and a SAW frequency shifter, arranged to operate with servos to maintain the CW and CCW ring resonances. The frequency difference between the CW and CCW resonances is a measure of the rotation rate. The equation for the gyro resolution is given, and some data are presented on prototype gyro performance. We discuss the differences between the cost and performance of this gyro and the fiber optic gyros.

Ring laser gyroscope based on standard single-mode fiber and semiconductor optical amplifier

Abstract: In this work, we present an optical gyroscope based on hybrid semiconductor-fiber ring laser. The proposed optical gyroscope is a Ring Laser Gyroscope (RLG), in which the laser cavity is a fiber ring of standard single mode fiber where a semiconductor optical amplifier is used as the gain medium for the ring laser. Taking advantage of the bidirectional nature of the ring laser cavity, two counter-propagating waves are supported in the ring cavity. The two waves are identical in terms of their optical resonance frequency due to the reciprocity of the loop in the static position. A frequency shift is introduced between the two counter-propagating waves when the loop is subjected to an angular rotation, known as the Sagnac effect, and the magnitude of the shift is proportional to the rotation rate. Due to the multi-longitudinal mode nature of the constructed ring laser, the rotation sensor optical system parameters are optimized in a trade-off between the sensitivity and the dynamic range. Special signal processing algorithms are developed to enhance the RLG sensitivity. The performance of the RLG is evaluated using a rate table and the Allan variance of the sensor is extracted. The demonstrated RLG has an excellent linear scale factor with a dynamic range up to 40°/sec and a sensitivity down to 0.2°/sec. The RLG noise specifications as extracted from the Allan variance are a bias instability of 3°/h and an angular random walk of 0.5°/Vh.

Dither-motor design with concurrent sensing and actuating piezoelectric materials (Ring laser gyroscope)

Abstract: The authors present an analytical model to predict the model parameters of a dither-motor structure in a ring laser gyroscope in which the piezoelectric sensor and actuator are employed as driving mechanisms to avoid the problem of so-called lock-in effects It is shown that the natural frequency of a dither motor is strongly influenced by: (1) the inertia and stiffness of piezoelectric elements and bonding layers, (2) the location of piezoelectric elements, and (3) the interaction between structural vibration and piezoelectric actuation Conventionally piezoelectric elements are used for sensor and actuator independently A technique for utilizing each of the piezoelectric elements concurrently for dither rate sensing and dither motion actuation is also developed Experimental results show that the system performance and reliability can be significantly increased by accurately predicting the fundamental structural frequency and by implementing the concurrent sensing/actuating technique