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.

Mechanically dithered laser gyroscope sensing axis dynamic offset error parameter estimating and compensating method

Abstract: The invention belongs to the field of inertial navigation, and discloses a mechanically dithered laser gyroscope sensing axis dynamic offset error parameter estimating and compensating method. The method comprises the following steps: 1, establishing the kinetic equation of the dynamic offset deformation angle of a mechanically dithered laser gyroscope sensing axis; 2, simplifying the kinetic equation of the dynamic offset deformation angle of the mechanically dithered laser gyroscope sensing axis; 3, establishing the dynamic offset error model of the mechanically dithered laser gyroscope sensing axis; 4, establishing the parameter of the dynamic offset error model of the mechanically dithered laser gyroscope sensing axis; and 5, compensating the dynamic offset error of the mechanically dithered laser gyroscope sensing axis to realize compensation of the dynamic offset error of the mechanically dithered laser gyroscope sensing axis under a vibrating condition. The method solves the problem of influences of the dynamic offset of the mechanically dithered laser gyroscope sensing axis on the precision of the inertial navigation system under the vibrating condition, and can be further applied to error compensation of the mechanically dithered laser gyroscope inertial navigation system under large-overload and high-maneuverability conditions.

Dither Signal Filtering in Ring Laser Gyroscope Using Modified Stockwell Transform

Abstract: Ring laser gyroscopes (RLGs) are widely used in many airborne and navigation systems for accurate measurement of the true rotation of the body movement, but the RLGs suffer a serious problem at low frequencies known as lock-in frequency To avoid the lock-in problem, the RLG is vibrated mechanically to a high frequency, which is known as dithering In order to get the true rotation of the body, the dither signal has to be removed Normally, digital filters are used to remove the dither signal These filters have the disadvantage that either the filter length is too large or the phase characteristics are not linear The Stockwell transform and the modified Stockwell transform (MST) are widely used for the analysis of signals In this article, the MST is used as a filter to filter the dither signal, which is attenuated by 1145dB

Study of Laser Gyro Temperature Compensation Technique on LINS

Abstract: Laser gyroscope is a high precision optical angular rate sensor. The stability of the Laser gyro output directly affects the navigation accuracy of the laser gyro inertial navigation system (LINS). On base of analyzing the error model of LINS, the temperature compensation model of laser gyroscope is established. The temperature compensation model of the gyro bias is established and the gyro bias is compensated with the method of subsection Hermite interpolation. Data collection and temperature compensation experimentations of the laser gyro in different temperature conditions are designed and completed. The output of the laser gyro is compensated off-line by the gyro pulse compensation model. The gyro bias is recalculated using the compensated gyro calibration data in order to validate the affection of the gyro temperature compensation method. Experiments show that the compensation effect of this temperature compensation method is visible. The laser gyro static output stability is improved more than 3 times at room temperature. Experiments show that this method has high engineering application value.

Multi-wavelength ring laser gyroscope

Abstract: PURPOSE:To make it unnecessary to insert a Faraday element into the laser resonator by giving a bias for removing lock-in through utilization of application of the Faraday effect of the optical rotatory power substance in the resonator. CONSTITUTION:In the 4-wavelength ring laser, a crystal is used for isolation of counterclocked circularly-polarized mode and clockwise circularly-polarized mode. A crystal has the Faraday effect in the same axial direction, and its Verdet's constant is 0.019min/cm.Oe. Therefore, it is possible to give the function of Faraday element by giving a field to a crystal. According to this structure, it is not required to insert the Faraday element into the laser resonator, and therefore a cause of giving adverse effect on the laser oscillation such as reflection absorption misalignment at the end surface of Faraday element can be eliminated. In the attached Figure, 1 is a Faraday element having optical rotatory power and 2 is a mirror, 3 is an electromagnet.

Combining optics for ring laser gyro

Abstract: The apparatus of this invention uses a rectangular-parallelepiped prism to extract portions of the counterpropagating beams from a ring laser of a gyro. Such prism is easier to build than prisms having other than right angles. One beam bounces within the prism, but it is not perfectly reflected, and a portion of the beam is transmitted to a sensor to control the length of the ring laser cavity. The two beams are combined to produce a heterodyne signal by using two partly transmissive mirrors on two parallel surfaces of the prism, and by positioning a third side surface at a critical angle relative to one of the beams.