卷 7, 编号 3 (2016)
- 年: 2016
- 文章: 12
- URL: https://journals.rcsi.science/2075-1087/issue/view/12683
Article
Calibration of a precision SINS IMU and construction of IMU-bound orthogonal frame
摘要
The paper focuses on construction of reference orthogonal frame bound with inertial measurement system of a strapdown inertial navigation system. Main points of the algorithm refining the FOG IMU calibration parameters in dynamic test bench conditions using the Kalman filter and relying upon the system navigation solution are detailed. Time lags in FOG gyros and accelerometers’ measurement channels are estimated to the accuracy allowing construction of a 0.001 deg/h class navigation system.
Compensation of excess RIN in fiber-optic gyro
摘要
The paper describes the sources of fundamental noises in FOG measurement signal. Methods of excess relative intensity noise (RIN) compensation are considered. Technique improving the compensation method using division of signals from two photodetectors for noise suppression is proposed and implemented. Functional simulation is conducted, which estimates the limiting theoretical value of noise suppression by the selected compensation method with the photodetector power of min 10 µW. Test results for FOG experimental prototype are presented. Allan variance plots for the cases with and without compensation are constructed.
A new generation of IRS with innovative architecture based on HRG for satellite launch vehicles
摘要
The satellite launch vehicles’ evolution goes through a reduction of cost, weight and size of the IRS (Inertial Reference System), while keeping a very high level of performance and safety compatible with this kind of application. The classic approach leads to duplicate this equipment, so assuring a first level redundancy. But this solution is not favourable considering the previous criteria (cost, weight, size) and does not allow detecting a possible slow drift of performance of one of the two IRS because there is no possible majority vote. The approach proposed in this paper is based on a multisensor architecture, integrating 6 gyroscopes and 6 accelerometers, with a triplication of the common functions, which allows using a non-radiation hardened electronics. This integrated architecture facilitates the implementation of FDI techniques (Fault Detection and Isolation), and withstands straight failures and performance drifts of the inertial sensors, the whole being integrated into a single equipment, which allows reducing drastically cost, weight and size. In this context, the use of HRG (Hemispherical Resonant Gyroscope) is particularly relevant because of its low size and weight. As a result, the proposed architecture allows reaching high levels of accuracies, which makes it capable of a wide range of missions. This paper details the proposed inertial and electronic architecture, demonstrates the techniques used for the FDI function and shows the contribution of the HRG for this kind of architecture in terms of accuracy, safety and size.
How the reference voltage of electromagnetic control sensors affects the drift of wave solid-state gyroscopes
摘要
Oscillation dynamics of a wave solid-state gyroscope with a resonator in the form of a thin elastic rotary shell mounted on a movable base is considered. A new mathematical model of the gyroscope, describing nonlinear interrelated electromagnetic and mechanical oscillations in the case that the coils of electromagnetic sensors carry voltage has been developed. Analytical estimation and numerical evaluation of the gyroscope errors have been performed.
Inertial measurement unit of waverider buoy. Development and test results
摘要
The paper focuses on development and studies of inertial measurement unit of a waverider buoy based on MEMS sensors. The model for estimating the accuracy of IMU algorithms is developed and studied, selection of time constants for orientation system and the vertical channel is validated, error in the wave elevation is estimated. The bench tests of IMU produced based on the results of these studies have confirmed the obtained conclusions and the error level.
Relative positioning calibration method of phase center offsets of GPS signal antennas
摘要
Phase center offset (PCO) of GPS antenna has a considerable influence on the precision and accuracy of the resulting coordinates. As joint observation mode of various GPS receivers and antennas becomes increasingly universal, efficient determination of PCO values of multi-type dual-frequency GPS receiver antennas at the same time needs to be addressed urgently. According to the property of antenna PCO, a relative positioning calibration method, which is based on GPS relative positioning survey theory, is proposed. This method only needs two steps, each being a simultaneous observation of one consecutive sidereal day for the reference antenna and the calibrated antenna. Experimental results for several widely used GPS antennas show that this method greatly improves the calibration efficiency and can estimate horizontal PCOs for both frequencies. The proposed method can be fully applied to synchronously assess PCOs of multi-type dual-frequency GPS antennas in high precision position.
Algorithms and design of longitudinal gyroinclinometer for vertical parts of wellbores
摘要
Existing designs and ideal algorithms of various types of gyroinclinometers (GI) (including those earlier rejected designs) are analyzed to study the errors of continuous survey of vertical parts of wellbores. Modernized structure and new algorithms using the structural redundancy specially created in longitudinal GI are proposed. Analytical study of the accuracy of synthesized scheme is accompanied by abundant mathematical modeling and results from practical operation.
Prospective development of the Russian geodetic reference network as a component part of the unified system for positioning, navigation, and timing
摘要
Proposals for improving the structure of the Russian geodetic reference network as a physical implementation of the terrestrial reference frame and one of the most important components of a unified system for positioning, navigation, and timing.
Development of the global geoid model based on the algorithm of one-dimensional spherical Fourier transform
摘要
An algorithm for constructing a model of the global geoid with zero-order approximation accuracy is considered. The algorithm is based on the one-dimensional spherical fast Fourier transform (FFT). It is 2.5 orders faster than those using the conventional discrete transform, and four orders, as compared with those using the numerical integration method. The algorithm was tested on the new Earth gravitational model EGM2008 published by the U.S. National Geospatial-Intelligence Agency (NGA).
Estimating the navigation informativity of the Earth’s anomalous gravity field
摘要
Application of modern global geopotential models to estimate the navigation informativity of the Earth’s anomalous gravity field (EAGF) is considered from the viewpoint of its use in autonomous (correlation- extreme) navigation. Various algorithms for calculating the characteristics of route and area navigation informativity, for which the authors use the variance and correlation radius of a measured EAGF parameter, are presented. The results of the experimental studies on estimation of the EAGF navigation informativity are discussed by analyzing vertical deflections and second derivatives of the perturbing potential in the Sea of Okhotsk with the use of the model EGM-2008 to degree 2190. It is shown that second derivatives of the geopotential demonstrate higher informativity as applied to navigation purposes.
Integrated navigation and local mapping system for a single-axis wheeled module
摘要
The paper considers a design of integrated navigation system of a single-axis wheeled module used to perform various functions in airdrome infrastructure. The core of the integrated navigation system is a strapdown inertial navigation system integrated with a video camera and dynamic model of a single-axis wheeled module with nonholonomic contact with underlying surface. The integrated navigation system simultaneously estimates the module navigation parameters and the coordinates of the landmarks observed by the video camera. The system is shown to determine the navigation parameters and to construct the structural map of landmarks over rather long periods without external aiding.
Distributed integrated navigation systems for planetary defense against asteroids
摘要
The main objectives of this paper are to give an interdisciplinary overview of the current status of the research on planetary defense against asteroids, which is a real challenge, and consider technical proposals on the development of a multilevel planetary defense system based on modern space technologies, providing for the application of projectile asteroids to deflect target asteroids’ trajectories and distributed integrated navigation systems, the navigation equipment of which is supposed to be installed on many different objects. The composition of such navigation systems and their accuracies are discussed. This work is based on the results obtained by the international Research Laboratory of Space Research, Technologies, Systems and Processes [1], founded at Moscow Institute of Electronics and Mathematics (MIEM), Branch of Higher School of Economics (HSE) in 2011. The project was supported by the grant of the Government of the Russian Federation (2011–2013) [2, 3]. We have also used pioneering ideas from the course of lectures Models of planetary defense [4], prepared at the Department of Mechanics and Mathematical Modeling, MIEM NRU HSE in 2014 [4].