伺服机构故障下运载火箭控制分配方法研究（英文）

This paper investigates the servo mechanism reconfiguration and fault tolerance control issue for a launch vehicle. Firstly, the servo reconfiguration algorithm is considered as an optimization model, and commonly used optimization algorithms are analyzed and compared. An improved method based on Singular Value Decomposition(SVD) for solving the suboptimal solution of the direct assignment problem is proposed, being suitable for engineering application, while maintaining the advantages of existi...     

Recent Developments on Damage and Fracture of Thin-Walled Complex Components Produced by Spinning

The spinning technique has been widely used in the manufacture of aerospace thin-walled axisymmetric components because of its excellent formability. Damage and fracture, as the important defects that often occur and must be avoided in the forming and service stages of components, have attracted much attention of researchers. In this paper, the fracture behavior and laws of spinning components such as conical parts, tubular parts, and components with inner ribs are summarized, the typical coupled and uncoupled ductile fracture models are introduced, and their applications in spinning are analyzed. Meanwhile, the recent developments on the modified ductile fracture model in analyzing damage and fracture mechanisms of spinning are emphatically introduced. The results could provide guidance for the selection and establishment of appropriate ductile fracture models in the finite element simulation for the accurate prediction and analysis of fracture moment, location, form, damage mechanism, and evolution law, and help the development of precision spinning techniques for high-performance thin-walled complex components.     

SJ-9A/B Satellites Conduct Key Technology Tests

On October 14, two satellites SJ-9A/B were sent into their preset orbits by a LM-2C/SMA launch vehicle, which is the first flight of a series of China’s civilian technology experimental satellites. SJ-9A and B are the first two satellites in the series of civilian technology experimental satellites designed for tests such as long lifetime and high reliability, high precision and high performance of satellite, domestically developed core components, satellite formation and     

China's Space Animal Experiments Obtained Achievements

Entering into the 1990s, Chinese scientists have made mice, drosophila and silkworm eggs experiments in space with satellites and achieved remarkable results. These animals were put in space environment units with the ability of adjusting pressure, temperature and moisture control, air conditioning and purifying as well as foods and water supply. After 8-days' flight, all performance parameters were normal and met the design requirements. The two mice kept alive for 5 days and 10 hours in     

LM-7 Prepares for Its Maiden Flight in 2016

<正>The LM-7 launch vehicle passed the joint review organized by CASC and CALT in June.Experts in the review team concluded that the LM-7 launch vehicle had completed the RD of the prototype phase and is able to enter flight test phase since the technical state of LM-7 for the flight test has been determined.The emphasis of the RD for the flight test phase will be put on the production,general assemble and test of the launch vehicle.     

China Will Develop New Materials for Heavy Launch Vehicles

The diameters of future heavy launch vehicles for manned lunar landing and deep space exploration are 1-2 times larger than those of the currently used Chinese rockets. To meet the requirement of high-stiffness, lightweight and high reliability by Extra-large resin matrix composites structures, the performance of future materials and processing level of large scale structures must be improved greatly than the existing system. The project of research on the engineering application of critical material system in structural composite material proposed by CASC     

CAECC Software Testing Laboratory Accredited by CNAL

Software Testing Laboratory ofChina Aerospace Engineeringand Consultation Center (CAECC)is accredited by China NationalAccreditation Board for Laboratories(CNAL) as the first such laboratory indomestic space industry. Since CNAL isa member of International LaboratoryAccreditation Cooperation (ILAC),software testing reports certificated toCAECC are recognized by 45 labora-tory accreditation organizations in Asia-Pacific region, Europe and America.The laboratory has more than ten…     

Application of Genetic Algorithm in Estimation of Gyro Drift Error Model

Extended Kalman Filter(EKF)algorithm is widely used in parameter estimation for nonlinear systems.The estimation precision is sensitively dependent on EKF’s initial state covariance matrix and state noise matrix.The grid optimization method is always used to find proper initial matrix for off-line estimation.However,the grid method has the draw back being time consuming hence,coarse grid followed by a fine grid method is adopted.To further improve efficiency without the loss of estimation accuracy,we propose a genetic algorithm for the coarse grid optimization in this paper.It is recognized that the crossover rate and mutation rate are the main influencing factors for the performance of the genetic algorithm,so sensitivity experiments for these two factors are carried out and a set of genetic algorithm parameters with good adaptability were selected by testing with several gyros’experimental data.Experimental results show that the proposed algorithm has higher efficiency and better estimation accuracy than the traversing grid algorithm.     

LM-5 Integrated Modal Test Completed

<正>The LM-5 integrated modal test was completed at the CALT next-generation launch vehicle industrial base in Tianjin.After 640 days’effort,the LM-5 rocket successively accomplished tests totalling23 technical states such as second-stage flight,first-stage flight,and rocket flight.The data obtained from the tests provided an important basis for rocket dynamic modal correction and the attitude control system.To fully test whether all performance indexes of the LM-5 rocket meet the requirement,the LM-5 rocket began     

Simplified Stub loaded Lines for Dual band Phase Offset at Two Operational Frequencies

]Dual band applications are usually encouraged in both active and passive radio frequency （RF） circuit design in perspective of their application in wireless communication systems.For example,in the field of Doherty power amplifier （DPA） design,one critical component is the design of phase offset lines used to avoid leakage of carrier amplifier current into peaking path.However,in case of dual band DPA design,such optimization in a dual band design needs dual band phase offset lines with arbitrary electric lengths at the two frequencies. In this letter,the simplified stub loaded lines are proposed to design dual band phase offset lines analytically.This design can achieve arbitrary phase shift at two operational frequencies by using Pi type with a dual band stub loaded line （DSL）.For verification,the proposed dual band phase offset lines are designed,implemented, and characterized at 1620 and 2750 MHz.The measured results of the fabricated phase offset lines agree well with the electromagnetic simulations, which shows the proposed structure is a good candidate for dual band Doherty power amplifier designs.     

A Robotic TeleoperationSystem for Precise Robotic Manipulation by Human-Machine Interaction

Teleoperation is of great importance in the area of robotics， especially when people are unavailable in the robot workshop. It provides a way for people to control robots remotely using human intelligence. In this paper， a robotic teleoperation system for precise robotic manipulation is established. The data glove and the 7-degrees of freedom (DOFs) force feedback controller are used for the remote control interaction. The control system and the monitor system are designed for the remote precise manipulation. The monitor system contains an image acquisition system and a human-machine interaction module， and aims to simulate and detect the robot running state. Besides，a visual object tracking algorithm is developed to estimate the states of the dynamic system from noisy observations. The established robotic teleoperation systemis applied to a series of experiments， and high-precision results are obtained， showing the effectiveness of the physical system.     

Space Technological Cooperation and Application in the Asia-Pacific Region

With the multipoiar-ization of international economy and regional realignment,the Asia-Pacific economy is thriving and prospering day by day.The demands for resources exploration and development and environmental monitoring and protection using space technology are increasing.Especially,since the United Nations Environmental and Development Congress held in Rio de Janeiro of Brazil,many countries have made their action programs correspondingly based on the Agenda 21.In accordance with the two themes on Development and Environment of global concern,many countries and international organizations in the Asia-Pacific region have been taking some new policies,and are participating in and appealing for the international cooperations in space technology.Whether having the abilities of developing space technology or not,these countries have expressed the common aspiration for making full use of space application potentiality and strengthening space application to improve regional sustainable development of soci     

Landing Stability Testing of the 3rd Phase of Lunar Exploration Project Ended

The Beijing Institute of Space Mechanics and Electricity,CAST completed the first phase tests of the landing stability testing for the 3rd phase of the Lunar Exploration Project.The tests fully verified the impacts on the Chang’e 5 probe landing stability of the landing initial parameters of the simulator in 8 working states and 18 operating modes,landing surface terrain and mechanical param-     

Enhancing Space Debris Studies

With the expansion of hu-man activities in space and thesteady increase in space debris re-sulting therefrom,the space envi-ronment is constantly deteriorat-ing.The space debris hazard hasalready introduced new safety is-sues for consideration by space a-gencies,spacecraft designers,manufacturers,scientists and in-surance underwriters. The problem of the pollutionof the space environment causedby space debris has become agrowing concern within interna-tional astronautical circles and theinternational community as awhole. And the management of thespace environment is a matter forinternational cooperation and all     

Address to Ministerial Conference on Space Applications for Development in Asia and the Pacific by the Chinese Delegation

First of all, please allow me, on behalf of the Chinese Government and the Chinese people, to convey my congratulations on the opening of the Ministerial Conference on Space Applications for Development in Asia and the Pacific. As a host country, we are grateful to Economic and Social Commission for Asia and the Pacific for its preparations for the Conference and grateful to the countries in Asia and Pacific region for their trust in and support to us. I believe we will reach common understanding on some important issues through discussion of     

Repair Welding of Casting Magnesium Alloys： A Review

Magnesium (Mg) alloys have broad application prospects in the fields of aerospace, national defense, and military industries, owing to their advantages of high specific strength and stiffness, good damping properties, and excellent castabilities. However, defects such as oxidation inclusions, shrinkage cavities and porosities, and hot cracks are readily generated in Mg alloy components, which seriously reduce the performance stability of the products. Related repair welding technologies for Mg alloys can greatly reduce the rejection rate and production cost, and exhibit significant value in scientific research and engineering application. In this review, the weldability of Mg alloys is introduced firstly according to their physical and chemical properties. Then, various repair welding technologies and pre-weld treatments applicable to Mg alloys are systematically summarized, and the effects of welding parameters as well as heat treatments on the microstructure and performance of the repaired joints are clarified. Finally, the existing problems and development trends of repair welding technologies for Mg alloys are summarized based on the actual engineering application requirements.     

Development of CMG for Space Station Has Entered A New Phase

<正>The development of a large singlegimbal control momentum gyro(CMG)for the space station developed by the Beijing Institute of Control Engineering(BICE)has entered a new phase.The next-generation CMG product with the largest output torque and the most complicated structure in China is under commissioning.Once being put into operation,it can meet the requirements of attitude control for large spacecraft and     

Prototype of China's Mars Rover Under Smooth Development

<正>Mars orbiting,landing and roving are expected to be achieved during China’s first Mars exploration mission,disclosed at the working meeting of the rover system for the mission held on March 1,2017.The mission,covers a complicated process,requiring large technical leaps,many critical links and huge engineering challenges,is of great significance in promoting advancement of space technology and the     

大功率高电压电动伺服系统在运载火箭上的应用研究（英文）

The 30 kW high-power electric servo system used in the solid booster of the Long March 6 A(LM-6 A) launch vehicle is introduced, and the function, composition of the system as well as its constituent equipments are detailed. To solve the problem of out-of-tolerance in the system dynamic characteristics, an advanced correction network algorithm architecture and double notch filter were designed. Experimental verification was conducted to prove that the dynamic characteristics requirement under mu...