- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Rotation Sensing Lasers in General Relativity: Some Technical Notes and Current Advances
摘要： We review the current status of large ring laser gyroscopes having the potential to contribute to terrestrial measurements of general relativistic precessions. At this point in time, although these devices possess the raw sensitivity for such a measurement, they remain limited by long-term geometric instability, detection noise and imperfections in the physical models required to isolate geophysical effects. Furthermore, minute non-reciprocal biases provide a null-shift error and therefore no currently constructed laser system meets the requirement of absolute rotation rate sensing. Nevertheless, we are of the view that these are surmountable problems and the ability of ring laser gyroscopes to measure low frequency to DC signals has vastly increased in the last decade.
关键词： ring laser gyroscopes,Sagnac interferometry,earth rotation sensing
更新于2025-09-19 17:13:59
-
[IEEE 2019 IEEE International Conference on Space Optical Systems and Applications (ICSOS) - Portland, OR, USA (2019.10.14-2019.10.16)] 2019 IEEE International Conference on Space Optical Systems and Applications (ICSOS) - Demonstration of Reliable High-Rate Optical Communication over an Atmospheric Link using ARQ
摘要： A quaternion-based attitude unscented Kalman ?lter is formulated with quaternion errors parameterized by small angle approximations and is applied to a ?lter with a state vector consisting of the attitude quaternion and the gyro bias vector. The ?lter is evaluated using extensive Monte Carlo data in a simulated lost-in-space scenario of a low-Earth orbiting spacecraft processing only three-axis magnetometer and gyro measurements. The ?lter is found to be robust, accurate, and rapidly convergent in this scenario for small true gyro biases and small initial uncertainties in their values, often converging in only one half of an orbit period to an attitude accuracy of 0.1 degrees. The ?lter convergence is found to depend signi?cantly on the value of the true gyro biases as well as the initial gyro bias covariances. Monte Carlo results also indicate that this unscented Kalman ?lter is signi?cantly less robust than an extended Kalman ?lter with the same attitude approach, but performs slightly better than another unscented Kalman ?lter with a generalized Rodrigues parameter approach to quaternion errors.
关键词： Attitude control,Kalman ?lters,gyroscopes,calibration,unscented,spacecraft,geomagnetism
更新于2025-09-19 17:13:59
-
A Calibration Method for the Errors of Ring Laser Gyro in Rate-Biased Mode
摘要： Ring laser gyro (RLG) can work in mechanically dithered mode or rate-biased mode according to the working state of the inertial navigation system (INS). It can change from one mode to the other by receiving outer instructions. To evaluate the performance of RLG in rate-biased mode, an inertial measurement unit (IMU) based on RLG is installed on a dual-axis turntable, the turntable offers a constant angular velocity to the RLGs, in that way RLG can work in the rate-biased mode. A calibration method is proposed to calibrate the scale factor error, misalignments and constant bias of RLG in rate-biased mode, experiment results show that the differences of scale factor of the three gyros in two modes are 9 ppm, 7 ppm and 3.5 ppm, the constant biases of the three RLGs in rate-biased mode are also different from that in mechanically dithered mode with the difference of 0.017°/h, 0.011°/h and 0.020°/h, the input axis misalignment angle of RLGs in different modes also changed. What is more, a calculation method of angle random walk (ARW) of RLG in rate-biased mode is also presented. Experimental results show that the ARW of the RLG in rate-biased mode is about one third of that in mechanically dithered.
关键词： ring laser gyroscopes,angle random walk,gyroscopes,calibration
更新于2025-09-12 10:27:22
-
Length measurement and stabilization of the diagonals of a square area laser gyroscope
摘要： Large frame ring laser gyroscopes are top sensitivity inertial sensors able to measure absolute angular rotation rate below prad/s in few seconds. The GINGER project is aiming at directly measuring the Lense-Thirring effect with an 1% precision on an Earth based experiment. GINGER is based on an array of large frame ring laser gyroscopes. The mechanical design of this apparatus requires a micrometric precision in the construction and the geometry must be stabilized in order to keep constant the scale factor of the instrument. The proposed control is based on square cavities, and relies on the length stabilization of the two diagonals, which must be equal at micrometric level. GP2 is the prototype devoted to the scale factor control test. As a first step, the lengths of the diagonals of the ring cavity have been measured through an interferometric technique with a statistical accuracy of some tens of nanometers, and they have been locked to the wavelength of a reference optical standard. Continuous operation has been obtained over more than 12 hours, without loss of sensitivity. GP2 is located in a laboratory with standard temperature stabilization, with residual fluctuations of the order of 1 ?C. Besides the demonstration of the control effectiveness, the analysis of the Sagnac frequency demonstrates that relative small and low-cost ring lasers (around one meter of side) can also achieve a sensitivity of the order of nrad/s in the range 0.01?10 Hz in a standard environment, which is the target sensitivity in many different applications, such as rotational seismology and next generation gravitational waves detectors.
关键词： Sagnac frequency,scale factor control,GINGER project,Lense-Thirring effect,ring laser gyroscopes
更新于2025-09-11 14:15:04
-
Non-Hermitian ring?laser gyroscopes with enhanced Sagnac sensitivity
摘要： Gyroscopes are essential to many diverse applications associated with navigation, positioning and inertial sensing1. In general, most optical gyroscopes rely on the Sagnac effect—a relativistically induced phase shift that scales linearly with the rotational velocity2,3. In ring laser gyroscopes (RLGs), this shift manifests as a resonance splitting in the emission spectrum, which can be detected as a beat frequency4. The need for ever more precise RLGs has fuelled research activities aimed at boosting the sensitivity of RLGs beyond the limits dictated by geometrical constraints, including attempts to use either dispersive or nonlinear effects5–8. Here we establish and experimentally demonstrate a method using non-Hermitian singularities, or exceptional points, to enhance the Sagnac scale factor9–13. By exploiting the increased rotational sensitivity of RLGs in the vicinity of an exceptional point, we enhance the resonance splitting by up to a factor of 20. Our results pave the way towards the next generation of ultrasensitive and compact RLGs and provide a practical approach for the development of other classes of integrated sensor.
关键词： Sagnac sensitivity,Non-Hermitian,ultrasensitive sensors,ring laser gyroscopes,exceptional points
更新于2025-09-11 14:15:04