Fiber Optic Gyro Sensor Research Articles

Comparative Analysis of the Efficiency of Fiber Winding Types Used in the Fiber-Optic Gyro Sensor Coil Under Temperature Variation Conditions

Background. The paper is devoted to the study of the effectiveness of different types of coil fiber winding of fiber optic gyro (FOG) in reducing of the impact of Shupe effect under temperature changes. Objective. The objective of the study is to evaluate the effectiveness of different types of FOG fiber coil winding under temperature changes. Methods. Based on the analysis of existing types of winding, and formulae for non-reciprocal phase shift calculation, a method for evaluation of the impact of temperature gradient on coils with different types of winding is created. Method mentioned is applied to 9 different types of coil winding. Results. The dependencies of zero shift vs time for nine types of winding under the impact of axial, radial temperature gradients and combinations thereof are obtained. Conclusion. Overall, use of quadruple windings seems to be optimal; for low precision sensors one can recommend centered unipolar winding while ensuring good thermal and vibration insulation of the coil. The use of pads (or frameless coils) is justified when simple winding is used (e.g., in devices for short-living objects, for automotive industry, etc.), or for high-precision sensors.

Online estimation of Allan variance coefficients based on a neural-extended Kalman filter.

As a noise analysis method for inertial sensors, the traditional Allan variance method requires the storage of a large amount of data and manual analysis for an Allan variance graph. Although the existing online estimation methods avoid the storage of data and the painful procedure of drawing slope lines for estimation, they require complex transformations and even cause errors during the modeling of dynamic Allan variance. To solve these problems, first, a new state-space model that directly models the stochastic errors to obtain a nonlinear state-space model was established for inertial sensors. Then, a neural-extended Kalman filter algorithm was used to estimate the Allan variance coefficients. The real noises of an ADIS16405 IMU and fiber optic gyro-sensors were analyzed by the proposed method and traditional methods. The experimental results show that the proposed method is more suitable to estimate the Allan variance coefficients than the traditional methods. Moreover, the proposed method effectively avoids the storage of data and can be easily implemented using an online processor.

Mathematical models of thermal stress-strain state and scale factor error of fiber optic gyro sensors

Mathematical and finite-element models for thermal stress-strain state of the “reel-fiber coil” system precision fiber optic gyro sensor are constructed and studied. An idealized design of the system and the real “reel-fiber coil” are considered. The solution of the thermoelastic contact problems for these systems, qualitative and quantitative evaluations of their mode of deformation, strength, and scale factor errors were obtained. A comparative analysis of systems is carried out and recommendations for improving the accuracy of the sensor are made.

Focus on lasers and optics

Focus on lasers and optics

自動自差修正이 가능한 電子컴퍼스의 개발에 관한 연구

The Electronic compass made as a pilot model in this research is comprised of a three axis magnetic sensor, an accustar clinometer, and a fiber optic gyro sensor. The results confirming the output character, performance, and the accuracy of the deviation corrects of each sensor are as follows: 1) As for the output character of the three axis magnetic sensor, the magnetic field showed a cosine curve on the X axis, a - sine curve on the Y axis, and constant figures on the Z sensor. The horizontal component H and the vertical component V of the terrestrial magnetism calculated from the output voltage were 33.2T and 23.95T respectively. 2) When the fiber optic gyro sensor is fixed on the electromotive rotation transformation and has made a clockwise rotation with the speed of 10/sec, 20/sec, and 30/sec, the relationship between the output and the rotation angle of the fiber optic gyro sensor showed proportionally constant values. 3) When the magnetic field was induced with a magnet, the deviation before the correction was significant at a high of 25. However, the deviation after the correction using Poisson correction was in the 2 range, significantly lower than before the correction. It was confirmed that automatic deviation corrects are possible with the electronic compass made as a pilot model in this research.

Utilization of Fiber Optic Gyros in Inertial Measurement Units

Fiber optic gyro technology has been developed to a point where these gyros are now being introduced into advanced engineering models of the next generation of inertial measurement units (IMUs). This paper covers the operating principles of the interferometric type of fiber optic gyroscopes, together with a brief comparison against ring-laser gyroscopes. Recent flight test data of an IMU employing fiber optic gyro sensors are presented. Finally, the unique characteristics of the fiber optic gyro are discussed, with particular emphasis on the role they will play in future fault-tolerant IMUs.