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.

Ring laser gyro employing radio frequency for pumping of gain medium

Abstract: A ring laser gyro (10) comprising a ring laser gyro block (24) having a gain bore (11, 12, 13) filled with a gain medium and apparatus for transmitting RF energy embedded within the ring laser gyro block (24) proximate to the gain bore (11). The RF energy apparatus (30) may be located so as to encompass the gain bore. Apparatus for providing RF energy (30) is connected to the RF energy transmitting apparatus (22, 40, 42).

A laser gyroscope system to detect the gravito-magnetic effect on Earth

Abstract: Ring lasers are inertial sensors for angular velocity based on the Sagnac effect. In recent years they have reached a very high sensitivity and accuracy; the best performing one, the ring Laser G in Wettzell (Germany), a square ring with 16 m perimeter, has reached a sensitivity of 12prad/s very close to the shot noise limit inferred from ring-down time measurements. On this basis it is expected that an array of six square ring lasers of 36 m perimeter, can perform a 1% accuracy test for the measurement of the Lense-Thirring frame dragging after 2 years of integration time. Essential for this measurement is the comparison between the Earth angular velocity and orientation in space measured with the ring array and compared to the measurement series maintained by the International Earth Rotation and Reference System Service (IERS), which measures Earth Rotation and pole position with respect to remote quasars. It has been shown that the accuracy of G in Wettzell is limited by the low frequency motion of the near surface laboratory, which is of the order of several prad/s, roughly 100 times larger than the Lense-Thirring contribution. For this reason the entire experiment should be placed in a quite underground laboratory, where these perturbations are reduced. The feasibility to properly place such a device inside the GranSasso INFN National Laboratory has been investigated.

Method and system for minimizing angular random walk or bias in a ring laser gyroscope through the use of temperature based control

Abstract: A system and method is provided which minimizes angular random walk or bias occurring in ring laser gyroscopes as a result of temperature changes. Temperature is known to affect components in a ring laser gyroscope in a manner which increases angular random walk or bias. By detecting temperature and causing movable path length transducers to move mirrors in the gyroscope into a position previously determined for a given temperature, angular random walk or bias is minimized for the given temperature.

The Performance Modeling of Ring Laser Gyro In Inertial Navigation

Abstract: In this paper, the performance of a Ring Laser Gyro based inertial navigation is studied. It is modeled by using two methods; in the dynamic modeling, some parameters such as scale factor and environmental sensitivity have been determined, whereas in the statistical model, the other parameters such as random drift have been computed. Also the performance of the system is evaluated for several inputs and the dither influences on Gyro's output, locking effect, scale factor and drift errors are investigated.

Phase modulation of a ring-laser gyro - Part II: Experimental results

Abstract: Experimental results are presented for the multimode ring-laser gyro with intracavity phase modulation. By proper choice of modulator frequency, the oppositely directed traveling waves (ODTW) exist as either pulse trains or FM signals. Conditions have been achieved, depending upon the time at which pulses arrive at the modulator, in which lock in between ODTW does not occur at low rotation rates. This result is not adequately explained, but is clearly useful for rotation sensing. In this condition, rotation sensitivity is noise limited and shows an improvement of two orders of magnitude over the same system without modulation. When lock in does occur, it is accompanied by a hysteresis effect that is explained in terms of an optical damage effect in the KDP modulator crystal. In the FM region of operation, the beat frequency between ODTW contains an offset that drifts with time and so this region of operation is not as useful for rotation sensing as is the pulse-train region.