Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper describes an interferometric fiber-optic gyroscope (IFOG) of a new configuration, i.e., with a birefringence modulator (IFOG-BRM) is proposed. According to the proposed scheme, a prototype model of the device has been assembled and tested to estimate its drift on a stationary base. Dependence of the IFOG-BRM drift on the temperature has been determined. According to the test results, the error of angular rate estimation is 0.05 deg/h; however, high sensitivity of the device to the absolute temperature variations has been revealed. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper studies the possibility of updating the parameters of error model of a rotating inertial measurement unit (IMU) with fiber-optic gyroscopes (FOG) in a strapdown inertial navigation system (SINS) under operating conditions. The IMU is placed in a two-axis gimbal for modulation rotation. The main focus is made on the estimation of scale factor errors of the FOG and accelerometers, non-orthogonality of their sensitive axes, and relative time delays (group delays) of inertial sensors during the IMU normal rotation according to the navigation solution of the INS in the observation mode of its operation. Also, the paper presents the description and results of estimation of so-called rhumb drifts of the IMU, which may occur due to the perturbing forces associated with the geographical axes or the axes of the system central device body. The research is based on the results of FOG-based INS simulation. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: — The past decade has been marked by an explosive growth in the number of missions with the use of small spacecraft weighing only about tens of kilograms, including CubeSats that are currently widely employed in various applications. For a scientific paper, it is no longer feasible to enumerate and properly analyze the accomplished missions as well as those under development and being planned: information changes so quickly that perhaps only websites with inline renovations can keep track of all the changes in this market. Near-Earth missions of CubeSats increasingly become the prerogative of engineers and production managers. Nowadays, even factories are built to mass-produce small spacecraft. However, interplanetary small-spacecraft missions stand apart because the technologies used to develop large spacecraft for interplanetary missions are not fully applicable to small spacecraft. The same is true of the ballistic aspects of such missions. This is primarily due to the low energy capability of small spacecraft for maneuvering and transmitting signals over long distances. The other equally important aspects are their self-sufficiency, navigation support, and radiation resistance in outer space. From the standpoint of the scientific novelty of the problems that spacecraft have to face and the fundamentals of ballistic implementation, it is interplanetary missions that attract attention of researchers. This paper discusses the opportunities for interplanetary transportation of small spacecraft and formulates the problems that need to be solved in the near future. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: Resonant modes of motion, manifested as a significant increase in the oscillation amplitude of the spatial angle of attack, can result in the failure of the CubeSat mission. This paper is concerned with the study of the resonant motion modes of aerodynamically stabilized CubeSat nanosatellites in low circular orbits with small inertia and mass asymmetry. In contrast to axisymmetric bodies of rotation, resonances in CubeSat nanosatellites can be caused not only by small asymmetry, but they also arise due to the form factor of the rectangular parallelepiped. Formulas have been obtained to determine the critical values of the nanosatellite longitudinal angular velocity at which the conditions for the emergence of resonant motion modes are fulfilled. An approach is proposed to prevent possible resonances for CubeSat nanosatellites. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper is devoted to the current problem of increasing the accuracy of magneto-optical laser gyros while maintaining their stable operation in real operating conditions. The problem is considered and studied by the example of the magneto-optical Zeeman laser gyroscope, which is one of the effective types of laser gyroscopes. The development and improvement of the technology for creating this type of gyroscopes makes it possible to significantly reduce the sources of the gyroscope zero drift and yet, retain the other properties and performance parameters. The study and validation of the possibility of a significant reduction in the gyroscope key control currents, such as the pumping currents of the active medium and the control currents of frequency bias, will increase the measuring accuracy of the gyroscope and, accordingly, the accuracy of navigation systems based on them. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: Abstract A robust and accurate real-time navigation system is crucial for autonomous robotics. In particular, GNSS denied and poor visual conditions are still very challenging as vision based approaches tend to fail in darkness, direct sunlight, fog, or smoke. Therefore, we are taking advantage of inertial data and FMCW radar sensors as both are not affected by such conditions. In this work, we propose a framework, which uses several 4D mmWave radar sensors simultaneously. The extrinsic calibration of each radar sensor is estimated online. Based on a single radar scan, the 3D ego velocity and optionally yaw measurements based on Manhattan world assumptions are fused. An extensive evaluation with real world datasets is presented. We achieve even better accuracies than state of the art stereo Visual Inertial Odometry (VIO) while being able to cope with degraded visual conditions and requiring only very little computational resources. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: This article discusses chances and challenges of using cold atom interferometers in inertial navigation. The error characteristics of the novel sensor are presented, as well as one option for an online estimation of the different readout errors. An extended Kalman filter framework is derived and analysed which uses the readout of the atom interferometer as observation in order to correct several systematic errors of a conventional IMU, allowing for an improved strapdown calculation in an arbitrary target system. The performance gain is discussed analytically based on the steady state variances of the filter, as well as on the example of a simulated scenario for Earth orbit satellites. The correction of the conventional IMU errors is further demonstrated in an experiment under laboratory conditions with a higher class sensor emulating an atom interferometer. While the application of the novel technology as a gyroscope is still limited, as pointed out in the paper, the presented framework yields options for a full six degree of freedom operation of the atom interferometer. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: In the first part of the paper, a polynomial filter has been proposed for filtering under quadratic nonlinearities both in the system and measurement equations. The second part details its features and advantages over the extended Kalman filter and illustrates them using a methodological example and examples of navigation data processing. PubDate: 2021-12-01
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: Abstract—The paper presents a brief history of preparation for, and execution of, the first manned mission on Vostok spacecraft. The key tasks and challenges met to make this historical event possible are discussed. Further achievements of Russian manned space missions are presented, including the world’s first orbital station Salyut built and launched in orbit 50 years ago. The role of people in space mission is studied. The in-orbit challenges are discussed, as well as their solutions that were found by the crews and improved the spacecraft safety and performance. Examples of crew operations during the missions of the Salyut orbital stations, Mir orbital facility, and the International Space Station are given to illustrate such challenges. The importance of cosmonauts’ participation in the research and experiments on the orbital stations is demonstrated, and positive examples of such participation are provided. PubDate: 2021-07-01 DOI: 10.1134/S2075108721030032
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: A new adaptive unscented Kalman filter (AUKF) is proposed to estimate the radio navigation parameters of a GPS signal tracking system in noisy environments and on a highly dynamic object. The experimental results have shown that the proposed AUKF-based method improves the GPS tracking margin by approximately 8 and 3 dB as compared to the conventional algorithm and the KF-based tracking, respectively. At the same time, the accuracy of Doppler frequency measurements increases as well. PubDate: 2021-07-01 DOI: 10.1134/S2075108721030044
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: 25 years ago, the CSRI Elektropribor proposed to use a gimballess electrostatic gyroscope (ESG) in spacecraft attitude reference systems. The system called BIS-EG passed the first flight tests in 2004. By 2013, 20 such systems had been manufactured for spacecraft of three types. The flight tests and regular operation of BIS-EG revealed a number of limitations inherent in them; at the same time, calibration methods were developed and tested and the ways of improving the system accuracy and reliability were identified. As a consequence, BIS-EG was upgraded for the next generation spacecraft, and it is still in operation. The distinctive features of this system are higher reliability, the gyroscope of greater stability, and in-flight calibration of its drift model. The next modification of the BIS-EG, which is under development now, must meet the requirements for higher accuracy characteristics and the need to work in the unpressurized spacecraft compartment. The stages and methods for improving the gimballess ESG and the BIS-EG family systems are described, as well as the results of their operation in accordance with their purposes in spacecraft of different types. PubDate: 2021-07-01 DOI: 10.1134/S2075108721030056
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: We examine two aspects specific to data fusion of strapdown inertial navigation systems (SINS) aided by global navigation satellite systems (GNSS), with their inherent spatial separation between the GNSS antenna phase center and the inertial measurement unit, as well as with SINS/GNSS synchronization errors. The first aspect refers to modifying the mathematical models used in INS/GNSS integration. The second one relates to our experience in their application in onboard airborne navigation algorithms developed by the Moscow Institute of Electromechanics and Automatics. PubDate: 2021-07-01 DOI: 10.1134/S207510872103007X
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper considers the filtering problems solved in navigation data processing under quadratic nonlinearities both in system and measurement equations. A Kalman type recursive algorithm is proposed, where the predicted estimate and gain at each step are calculated based on the assumption on the Gaussian posterior probability density function of the estimated vector at the previous step and minimization of estimation error covariance matrices using a linear procedure with respect to the current measurement. The similarities between this algorithm and other Kalman type algorithms such as extended and second-order Kalman filters are discussed. The procedure for evaluating the performance and comparing the algorithms is presented. PubDate: 2021-07-01 DOI: 10.1134/S2075108721030068
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: Abstract—The paper presents a method for identifying the frame of a star sensor (SS), based on determination of the star local features allowing its unique recognition. The star identifiers are located in a multidimensional integer feature space, and the relevant feature catalog presents a disperse array, which provides search-free star determination. Examples of onboard implementation of feature catalog are presented, containing the stars up to magnitude of six. The required memory is estimated, and a method is proposed for compressing the feature catalog to be recorded in the onboard computer memory. The frame identification algorithm using the reduced feature catalog is described in detail. The algorithm was tested on real sky frames. PubDate: 2021-07-01 DOI: 10.1134/S2075108721030020
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper describes an improved technology of quartz elastic system manufacturing for the gravimeters of Chekan series; its purpose is to automate the manufacturing processes of the elastic system elements to improve the work quality and performance. The elastic system manufactured using this technology has been tested on a bench and in field, and the results confirmed its compliance with the requirements set for the sensitive elements of modern mobile gravimeters. PubDate: 2021-04-01 DOI: 10.1134/S2075108721020073
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper presents the results of synthesis of calibration programs consisting of 9 and 18 measurement positions. The synthesis was performed by numerical methods for scalar (invariant) technique of accelerometer unit calibration. The resulting programs are compared to the existing calibration programs which have been obtained analytically. The results of mathematical simulation and field experiment confirm the theoretical calculations, as well as the effective application of the obtained calibration programs. PubDate: 2021-04-01 DOI: 10.1134/S2075108721020036
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: — The critical functional part of any high performance resonance based sensor is a mechanical resonator. The performance is measured by resonator quality factor (Q-factor). Damping mechanisms such as thermoelastic damping (TED), anchor loss, surface loss, material internal friction, fluid damping and electronics damping are covered in this review with more focus on gyroscope resonators. Dissipations can be reduced by different means. Hence, the effects of various design to operational parameters on the Q-factor for different configurations, sizes and materials are reviewed in detail. Micro scale ring resonators can achieve a Q-factor of the order of hundreds of thousands. Macro scale hemispherical resonators are suitable for ultrahigh Q-factors. High temperature sensor operation is not preferred because of TED, while sub-zero operation is limited by material internal friction. Few orders of dissipation increase are seen with thin film metallic coating due to TED and coating material internal friction. High precision fabrication is mandatory to achieve the designed minimum anchor loss as it is highly sensitive to fabrication imperfections. Q-factor sensitivity to operating pressure is different for different resonator configurations. This review study helps to build a comprehensive mechanical resonator design, realization and operation strategy to achieve high sensor performance. A roadmap on future research requirements for developing compact mass producible CVG type sensors with ultrahigh Q-factor is also highlighted. PubDate: 2021-04-01 DOI: 10.1134/S207510872102005X
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper analyzes how random and systematic components of instrumental error of an automated astronomical system affect the accuracy of the landmark astronomical azimuth. The obtained results can be applied to construct the error mathematical model and to define the mutual orientation of the body axes when designing the system. PubDate: 2021-04-01 DOI: 10.1134/S2075108721020085
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The problem of a strapdown inertial navigation system (SINS) integration with an odometer as part of an integrated navigation system is considered. The odometer raw measurement is considered as an increment of the distance traveled along the odometer “measuring” axis. Models of the integration solution components for the case of three-dimensional navigation are presented, among which are the models of inertial autonomous and kinematic odometer dead reckoning (DR), models of relevant error equations, the model of SINS position aiding based on the odometer DR data and using GNSS position and velocity, wherever possible. The models comprise objective components, which do not depend on the type of the inertial sensors used and their accuracy grade, and variable components, which take into account the properties of the navigation sensors used. The integration does not require zero velocity updates, known as ZUPT correction, which are commonly used in navigation application. PubDate: 2021-04-01 DOI: 10.1134/S2075108721020048
Please help us test our new pre-print finding feature by giving the pre-print link a rating. A 5 star rating indicates the linked pre-print has the exact same content as the published article.
Abstract: The paper addresses the operating principles of a gyroscopic device of a new type: a gyroscope on de Broglie waves. The sensitive element of such a gyroscope is an atomic interferometer, whose main components are described and the technical challenges of its development are discussed. The target audience of this paper is the readers who do not have a profound knowledge of the quantum physics. PubDate: 2021-04-01 DOI: 10.1134/S2075108721020097
Hybrid journal (It can contain Open Access articles)
