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The pointing error definition metric and its statistical interpretation method is investigated in this paper. First, the pointing error is analyzed and defined from two aspects, namely, pointing precision error and pointing stability error, corresponding weight functions and their approximations are simulated to show the rationality. Then, twelve metric indicators are introduced with illustration...
Aiming at the problem of harsh operating condition of the space manipulator and not being able to support great collision Momentum, this paper proposes a new concept and technical method, called soft-contact technology. According to this, the paper designs a space manipulator joint configuration based on bionics and carries out its rigid-flexible composite characteristic simulation. Simulation results...
Cold expansion and interference fitting both can improve the fatigue life of 7075-T6 aluminum alloy single plates. To study the combination effect of the two techniques on fatigue life improvement, a numerical analysis method was employed to simulate the specimens with different cold expansion and interference fit degrees. Finite element methods were conducted to capture the residual stress, and the...
X-ray pulsar-based navigation method is a promising autonomous navigation method. The research has been done for nearly 30 years. Several key techniques about this method are the research hotspots now. One of the key techniques is estimation of the time of arrival (TOA) in pulsar's signal processing. The precision of the TOA would affect the precision of X-ray pulsar-based navigation. Using Monte...
There will be a big load on the structure after aircraft ditching and spacecraft water recycling, which has an important effect on the safety of the capsule structure and the people inside. Therefore the research of water impact has a practical significance. Base on the wedge and arc body model, the test of the body free falling on the water has been vertically investigated. The acceleration signals...
No restrictions are imposed on the motion states of missile and target and the line of sight rotation coordinate system is introduced into the derivation of differential geometric guidance law. Then, the extended differential geometric guidance law is achieved whose scope of application is largely extended. In order to realize the derived law, instead of the complex computation of torsion command,...
Electronic oxygen regulator has a high sensitivity to respiratory regulation, which is the development direction of future aircraft oxygen system. China has carried out the principle research of the electronic oxygen regulator, the pressure control cavity is a key component of the electronic oxygen regulator in the establishment of the excessive pressure. This paper introduces the operating principle...
In coupled-field studies, compatibilities of different fields' solutions are as important as the solutions themselves, as they directly affect the investigation results that the solutions of the individual fields are intended to provide. This paper aims to address this issue in fluid-structure-interaction (FSI) studies by proposing an effective framework with which the compatibility of the solid and...
The dynamics of angular motion of a space landing vehicle with an inflatable braking device under resonance conditions is studied in this paper. Calculations of the parameters of the angular motion of the landing vehicle are performed using the method developed by the authors, based on the assumption that the deformation of the inflatable braking device occurs in the plane of the spatial angle of...
Lucky imaging is a method of high resolution imaging without Adaptive Optics (AO) system, and widespread in astronomy and space target observation. We measured atmospheric conditions at Xinglong Observatory, and evaluated the feasibility for lucky imaging. Atmospheric seeing is acquired by Differential Image Motion Monitor (DIMM), of which the median value is 1.37". atmospheric dispersion is...
This paper presents a solution to autonomous inspection of the international space station using a rigid spacecraft. Specifically, the paper presents the orbital mechanics, formation dynamics as well as rotational dynamics required to control the spacecraft relative to the space station, and then presents two PD+ controllers enabling a spacecraft to track a series of waypoints while pointing a sensor...
LEO Satellites equipped with high-power microwave payloads bring special demands for fast charging of Lithium ion battery. However, charging polarization occurs in traditional constant current-constant voltage strategy for Li-ion battery, following by comparative long charging time. To realize fast charging of batteries, novel Li-ion battery fast charge topology and principle were present based on...
To solve the ascent guidance of reusable launch vehicle (RLV) under the uncertain condition, a robust guidance method based on combing feedback linearization and H-infinity optimization theory is proposed. The article establishes the RLV ascending dynamic models. According to the characteristics of the ascending flight, the height deviation is converted into a linear relationship with pitch angle...
Considering the expansion of new trends in production technologies, it is necessary to know as much as possible effects that influence quality of produced component. Sintering of metal powder brings many problems which is necessary to identify and consequently to solve. It is more important, if the parts are complex with thin walls and it is supposed that it will be used in the equipment with high...
The Slovak Organisation for Space Activities (SOSA) has been active in various types of space-related activities since its establishment in 2009. They include launching stratospheric balloons, the development of the first Slovak suborbital rocket ARDEA, a spaceflight simulator and many others. SOSA, together with the Žilina University in Žilina, the Slovak Technical University in Bratislava, the Technical...
In this study, a new fundamental modeling framework for solid field is proposed by means of which a two-way dynamic coupling between the solid and fluid fields can be attainable for identically-modeled fluid field. To this aim, using the physical decomposition framework proposed in [1], a domain-independent model that can demonstrate the reversible and irreversible energetic interactions between the...
The principle and application of harmonic motion drive is introduced. Aiming at spacecraft harmonic motion drive mechanism working in space environment, a set of transmission efficiency test and control system is designed. The structure and principle of the whole control system is described. the efficiency test method of a harmonic motion drive is designed. To improve the traditional test device,...
A new adaptive compensation control method was developed to improve the control performance of multivariable system which affected by uncertainty. In this paper, a basic optimal LQR control law was compensated by the augmented model reference adaptive method under the framework of feedback control structure, to improve the dynamic and anti-interference performance of the system which affected by uncertainty...
After contact with receiver aircraft, the nozzle of flying boom is locked into the receptacle of receiver which may generate a dangerous radial constrained force (RCF) with disturbance from environment. This paper presents a novel control method to eliminate the RCF. Based on the existing altitude dynamic function, the unloading dynamic model can be achieved by putting the RCF into the existing dynamic...
A hot-fire test of an experiment-scale Kero/GOX liquid rocket engine is carried out. Numerical simulation on the basis of the experiment is calculated with the purpose of verifying the validity of the numerical simulation model in this paper. After that, high frequency instability induced by the distribution of gas-liquid scheme injectors is studied numerically. There are three injectors distribution...
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